View Filing Data

Selling and administrative expenses

^[1]

$ 883

$ 753

$ 2,427

$ 2,144

Cost of sales

708

599

1,933

1,714

Gross profit

175

154

494

430

190

189

Research and technical expenses

Income from operations

251

188

Interest and dividend income

Interest expense

(9)

(10)

(29)

(30)

Other (expense) income

(5)

(2)

Income from continuing operations before income taxes and equity in net income of affiliated companies

^[2]

225

157

Provision for income taxes

(18)

(20)

(29)

(30)

Equity in net income of affiliated companies

^[3]

Income from continuing operations

202

132

Income from discontinued operations, net of tax

Net income

203

132

Net income attributable to noncontrolling interests

Weighted-average common shares outstanding, in millions:

$ 60

$ 47

$ 186

$ 119

Basic

64.7

63.9

64.6

63.7

Diluted

65.6

64.5

65.4

64.2

Basic:

Income from continuing operations attributable to Cabot Corporation

$ 0.93

$ 0.72

$ 2.82

$ 1.82

Income from discontinued operations

0.02

Income from continuing operations attributable to Cabot Corporation

0.93

0.72

2.84

1.82

Diluted:

0.92

0.72

2.79

1.81

Income from discontinued operations

0.02

Dividends per common share

0.92

0.72

2.81

1.81

$ 0.18

$ 0.54

[1]	Unallocated and Other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.
[2]	Unallocated and Other includes certain items and eliminations that are not allocated to the operating segments. Management does not consider these items necessary for an understanding of the operating results of these segments and such amounts are excluded in the segment reporting to the Chief Operating Decision Maker. Income (loss) from continuing operations before taxes that are categorized as Unallocated and Other includes:
[3]	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and Other to reconcile to segment EBIT.

Consolidated Balance Sheets - USD ($) $ in Millions	Jun. 30, 2011	Sep. 30, 2010
Current assets:
Cash and cash equivalents	$ 344	$ 387
Accounts and notes receivable, net of reserve for doubtful accounts of $5 and $4	697	576
Inventories:
Raw materials	133	121
Work in process	9	38
Finished goods	249	178
Other	43	36
Total inventories	434	373
Prepaid expenses and other current assets	73	72
Deferred income taxes	32	30
Total current assets	1,580	1,438
Property, plant and equipment	3,141	2,943
Accumulated depreciation and amortization	(2,111)	(1,968)
Net property, plant and equipment	1,030	975
Goodwill	41	39
Equity affiliates	58	61
Intangible assets, net of accumulated amortization of $13 and $12	4	4
Assets held for rent	46	40
Deferred income taxes	255	245
Other assets	88	84
Total assets	3,102	2,886
Current liabilities:
Notes payable to banks	61	29
Accounts payable and accrued liabilities	429	447
Income taxes payable	20	34
Deferred income taxes	6	6
Current portion of long-term debt	26	23
Total current liabilities	542	539
Long-term debt	578	600
Deferred income taxes	6	6
Other liabilities	341	324
Commitments and contingencies (Note E)
Preferred stock:
Authorized: 2,000,000 shares of $1 par value Issued and Outstanding : None and none
Common stock:
Authorized: 200,000,000 shares of $1 par value, Issued: 65,439,772 and 65,429,916 shares, Outstanding: 65,406,101 and 65,370,220 shares	65	65
Less cost of 33,671 and 59,696 shares of common treasury stock	(1)	(2)
Additional paid-in capital	60	46
Retained earnings	1,276	1,125
Deferred employee benefits	(16)	(20)
Accumulated other comprehensive income	126	88
Total Cabot Corporation stockholders' equity	1,510	1,302
Noncontrolling interests	125	115
Total stockholders' equity	1,635	1,417
Total liabilities and stockholders' equity	$ 3,102	$ 2,886

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2011	Sep. 30, 2010
Consolidated Balance Sheets
Accounts and notes receivable, net of reserve for doubtful accounts	$ 5	$ 4
Intangible assets, accumulated amortization	$ 13	$ 12
Preferred stock, authorized shares	2,000,000	2,000,000
Preferred stock, par value	$ 1	$ 1
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, authorized shares	200,000,000	200,000,000
Common stock, par value	$ 1	$ 1
Common stock, issued shares	65,439,772	65,429,916
Common stock, outstanding shares	65,406,101	65,370,220
Common treasury stock, shares	33,671	59,696

Consolidated Statements Of Cash Flows - USD ($)
$ in Millions

9 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Cash Flows from Operating Activities:

Net income

$ 203

$ 132

Adjustments to reconcile net income to cash provided by operating activities:

Depreciation and amortization

105

107

Deferred tax provision

(16)

Impairment charges

Loss on sale of property, plant and equipment

Equity in net income of affiliated companies

^[1]

(6)

(5)

Non-cash compensation

Changes in assets and liabilities:

Accounts and notes receivable

(96)

(142)

Inventories

(46)

(9)

Prepaid expenses and other current assets

(9)

Accounts payable and accrued liabilities

(39)

(7)

Income taxes payable

(14)

(11)

Other liabilities

(4)

Cash dividends received from equity affiliates

Other

Cash provided by operating activities

117

Cash Flows from Investing Activities:

Additions to property, plant and equipment

(129)

(57)

Proceeds from sales of property, plant and equipment

(Increase) decrease in assets held for rent

(7)

Investment in equity affiliate

(2)

Settlement of derivatives

(7)

Cash used in investing activities

(138)

(57)

Cash Flows from Financing Activities:

Borrowings under financing arrangements

Repayments under financing arrangements

(35)

(17)

Repayments of long-term debt

(20)

(6)

Increase (decrease) in notes payable to banks, net

(2)

Purchases of common stock

(9)

(5)

Proceeds from sales of common stock

Cash dividends paid to noncontrolling interests

(9)

(6)

Cash dividends paid to common stockholders

(35)

Proceeds from restricted stock loan payments

Cash used in financing activities

(35)

(39)

Effect of exchange rate changes on cash

(12)

Decrease in cash and cash equivalents

(43)

(9)

Cash and cash equivalents at beginning of period

387

304

Cash and cash equivalents at end of period

$ 344

$ 295

[1]	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and Other to reconcile to segment EBIT.

Consolidated Statement Of Changes In Stockholders' Equity - USD ($)
shares in Thousands, $ in Millions

Common Stock, Net Of Treasury Stock [Member]

Additional Paid-In Capital [Member]

Retained Earnings [Member]

Deferred Employee Benefits [Member]

Accumulated Other Comprehensive Income [Member]

Cabot Corporation Stockholders' Equity [Member]

Noncontrolling Interests [Member]

Total Comprehensive Income [Member]

Total

Balance, shares at Sep. 30, 2009

65,309

Balance, value at Sep. 30, 2009

$ 63

$ 18

$ 1,018

$ (25)

$ 60

$ 1,134

$ 103

$ 1,237

Foreign currency translation adjustment

119

$ 119

119

(4)

Total other comprehensive income (loss)

(4)

Comprehensive income attributable to Cabot Corporation, net of tax

^[1]

115

Net income attributable to noncontrolling interests, net of tax

(13)

Noncontrolling interests foreign currency adjustment

(4)

Comprehensive income attributable to noncontrolling interests, net of tax

^[1]

Comprehensive income

^[1]

124

Noncontrolling interests - dividends

(6)

Cash dividends paid to common stockholders

(35)

Issuance of stock under employee compensation plans, net of forfeitures, shares

193

Issuance of stock under employee compensation plans, net of forfeitures

$ 2

Amortization of share-based compensation

Purchase and retirement of common and treasury stock, shares

(205)

Purchase and retirement of common and treasury stock

$ (2)

(3)

(5)

Principal payment by Employee Stock Ownership Plan under guaranteed loan

Balance, shares at Jun. 30, 2010

65,297

Balance, value at Jun. 30, 2010

$ 63

1,102

(21)

1,235

106

1,341

Balance, shares at Sep. 30, 2010

65,370

Balance, value at Sep. 30, 2010

$ 63

1,125

(20)

1,302

115

1,417

Foreign currency translation adjustment

186

Change in unrealized loss on investments and derivatives, net of tax

(1)

Total other comprehensive income (loss)

Comprehensive income attributable to Cabot Corporation, net of tax

^[2]

224

Net income attributable to noncontrolling interests, net of tax

(17)

Noncontrolling interests foreign currency adjustment

Comprehensive income attributable to noncontrolling interests, net of tax

^[2]

Comprehensive income

^[2]

245

Noncontrolling interests - dividends

(11)

Cash dividends paid to common stockholders

(35)

Issuance of stock under employee compensation plans, net of forfeitures, shares

268

Issuance of stock under employee compensation plans, net of forfeitures

$ 1

Amortization of share-based compensation

Purchase and retirement of common and treasury stock, shares

(232)

Purchase and retirement of common and treasury stock

(9)

Notes receivable for restricted stock - payments

Principal payment by Employee Stock Ownership Plan under guaranteed loan

Balance, shares at Jun. 30, 2011

65,406

Balance, value at Jun. 30, 2011

$ 64

$ 60

$ 1,276

$ (16)

$ 126

$ 1,510

$ 125

$ 1,635

[1]	Comprehensive income for the three months ended June 30, 2010 was $49 million, which consists of comprehensive income attributable to Cabot Corporation, net of tax of $48 million and comprehensive income attributable to noncontrolling interests, net of tax of $1 million.
[2]	Comprehensive income for the three months ended June 30, 2011 was $86 million, which consists of comprehensive income attributable to Cabot Corporation, net of tax of $78 million and comprehensive income attributable to noncontrolling interests, net of tax of $8 million.

Consolidated Statement Of Changes In Stockholders' Equity (Parenthetical) - USD ($)
$ in Millions

3 Months Ended

9 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Jun. 30, 2011

^[1]

Jun. 30, 2010

^[2]

Consolidated Statement Of Changes In Stockholders' Equity

Comprehensive income

$ 86

$ 49

$ 245

$ 124

Comprehensive income attributable to noncontrolling interests, net of tax

Comprehensive income attributable to Cabot Corporation, net of tax

$ 78

$ 48

[1]	Comprehensive income for the three months ended June 30, 2011 was $86 million, which consists of comprehensive income attributable to Cabot Corporation, net of tax of $78 million and comprehensive income attributable to noncontrolling interests, net of tax of $8 million.
[2]	Comprehensive income for the three months ended June 30, 2010 was $49 million, which consists of comprehensive income attributable to Cabot Corporation, net of tax of $48 million and comprehensive income attributable to noncontrolling interests, net of tax of $1 million.

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 8, 9, 10, 11, 12, 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 30
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A5
-Appendix A

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e557-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=6518256

Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6519514

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6508144

Reference 9: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph c(3)
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to noncontrolling interests, if any. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

Basis Of Presentation

9 Months Ended

Jun. 30, 2011

Basis Of Presentation

Basis Of Presentation

A. Basis of Presentation

The consolidated financial statements include the accounts of Cabot Corporation ("Cabot" or the "Company") and its wholly owned subsidiaries and majority-owned and controlled U.S. and non-U.S. subsidiaries. Additionally, Cabot considers consolidation of entities over which control is achieved through means other than voting rights, of which there were none in the periods presented. Intercompany transactions have been eliminated in consolidation.

The unaudited consolidated financial statements have been prepared in accordance with the requirements of Form 10-Q and consequently do not include all disclosures required by Form 10-K. Additional information may be obtained by referring to Cabot's Annual Report on Form 10-K for the fiscal year ended September 30, 2010 ("2010 10-K").

The financial information submitted herewith is unaudited and reflects all adjustments which are, in the opinion of management, necessary to provide a fair statement of the results for the interim periods ended June 30, 2011 and 2010. All such adjustments are of a normal recurring nature. The results for interim periods are not necessarily indicative of the results to be expected for the fiscal year or any other period.

The amount included in the caption "Income from discontinued operations, net of tax" in the consolidated statements of operations represents a tax settlement in connection with the Company's discontinued operations. The settlement amount was a benefit of approximately $1 million for the nine months ended June 30, 2011.

The entire disclosure for organization, consolidation and basis of presentation of financial statements disclosure.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 2-6
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Name Statement of Position (SOP)
-Publisher AICPA
-Number 94-6
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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Significant Accounting Policies

Significant Accounting Policies

9 Months Ended

Jun. 30, 2011

Significant Accounting Policies

B. Significant Accounting Policies

Revenue Recognition and Accounts Receivable

Cabot recognizes revenue when persuasive evidence of a sales arrangement exists, delivery has occurred, the sales price is fixed or determinable and collectability is probable. Cabot generally is able to ensure that products meet customer specifications prior to shipment. If the Company is unable to determine that the product has met the specified objective criteria prior to shipment or if title has not transferred because of sales terms, the revenue is considered "unearned" and is deferred until the revenue recognition criteria are met.

Shipping and handling charges related to sales transactions are recorded as sales revenue when billed to customers or included in the sales price. Shipping and handling costs are included in cost of sales.

The following table shows the relative size of the revenue recognized in each of the Company's reportable segments.


	Three months ended						Nine months ended
	June 30						June 30
	2011			2010			2011			2010

Core Segment
Rubber Blacks Business		62	%		60	%		61	%		60	%
Supermetals Business		6	%		7	%		6	%		6	%
Performance Segment		28	%		27	%		28	%		28	%
New Business Segment		3	%		3	%		3	%		3	%
Specialty Fluids Segment		1	%		3	%		2	%		3	%

Cabot derives the substantial majority of its revenues from the sale of products in the Core and Performance Segments. Revenue from these products is typically recognized when the product is shipped and title and risk of loss have passed to the customer. The Company offers certain of its customers cash discounts and volume rebates as sales incentives. The discounts and volume rebates are recorded as a reduction in sales at the time revenue is recognized and are estimated based on historical experience and contractual obligations. Cabot periodically reviews the assumptions underlying its estimates of discounts and volume rebates and adjusts its revenues accordingly.

Revenue in the New Business Segment is typically recognized when the product is shipped and title and risk of loss have passed to the customer. Depending on the nature of the contract with the customer, a portion of the segment's revenue may be recognized using proportional performance.

The majority of the revenue in the Specialty Fluids Segment arises from the rental of cesium formate. This revenue is recognized throughout the rental period based on the contracted rental terms. Customers are also billed and revenue is recognized, typically at the end of the job, for cesium formate product that is not returned. On occasion the Company also makes sales of cesium formate outside of a rental process and revenue is recognized upon delivery of the fluid.

Cabot maintains allowances for doubtful accounts based on an assessment of the collectability of specific customer accounts, the aging of accounts receivable and other economic information on both an historical and prospective basis. Customer account balances are charged against the allowance when it is probable the receivable will not be recovered. Changes in the allowance during the first nine months of fiscal 2011 and 2010 were not material. There is no off-balance sheet credit exposure related to customer receivable balances.

Goodwill and Long-Lived Assets

Goodwill is comprised of the cost of business acquisitions in excess of the fair value assigned to the net tangible and identifiable intangible assets acquired. Goodwill is not amortized but is reviewed for impairment at least annually. The annual review consists of the comparison of each reporting unit's carrying value to its fair value, which is performed as of March 31. Certain circumstances may give rise to an impairment assessment at a date other than the annual assessment date.

The fair value of a reporting unit is primarily based on discounted estimated future cash flows. The assumptions used to estimate fair value include management's best estimates of future growth rates, operating cash flows, capital expenditures, discount rates and market conditions over an estimate of the remaining operating period at the reporting unit level. If an impairment exists, a loss is recorded to write-down the value of goodwill to its implied fair value.

Cabot's long-lived assets primarily include property, plant and equipment, long-term investments, assets held for rent and intangible assets. The carrying values of long-lived assets are reviewed for impairment whenever events or changes in business circumstances indicate that the carrying amount of an asset may not be recoverable.

Financial Instruments

Cabot's financial instruments consist primarily of cash and cash equivalents, accounts and notes receivable, accounts payable and accrued liabilities, short-term and long-term debt, and derivative instruments. The carrying values of Cabot's financial instruments approximate fair value with the exception of long-term debt that has not been designated as part of a fair value hedge. The non-hedged long-term debt is recorded at amortized cost. The fair values of the Company's financial instruments are based on quoted market prices, if such prices are available. In situations where quoted market prices are not available, the Company relies on valuation models to derive fair value. Such valuation takes into account the ability of the financial counterparty to perform.

Cabot uses derivative financial instruments primarily for purposes of hedging exposures to fluctuations in interest rates and foreign currency exchange rates, which exist as part of its on-going business operations. Cabot does not enter into derivative contracts for speculative purposes, nor does it hold or issue any derivative contracts for trading purposes. All derivatives are recognized on the consolidated balance sheets at fair value. Where Cabot has a legal right to offset derivative settlements under a master netting agreement with a counterparty, derivatives with that counterparty are presented on a net basis. The changes in the fair value of derivatives are recorded in either earnings or accumulated other comprehensive income, depending on whether or not the instrument is designated as part of a hedge transaction and, if designated as part of a hedge transaction, the type of hedge transaction. The gains or losses on derivative instruments reported in accumulated other comprehensive income are reclassified to earnings in the period in which earnings are affected by the underlying hedged item. The ineffective portion of all hedges is recognized in earnings during the period in which the ineffectiveness occurs.

In accordance with Cabot's risk management strategy, the Company may enter into certain derivative instruments that may not be designated as hedges for hedge accounting purposes. Although these derivatives are not designated as hedges, the Company believes that such instruments are closely correlated with the underlying exposure, thus managing the associated risk. The Company records in earnings the gains or losses from changes in the fair value of derivative instruments that are not designated as hedges. Cash movements associated with these instruments are presented in the consolidated statement of cash flows as cash flows from operating activities because the derivatives are designed to mitigate risk to the Company's cash flow from operations.

Income Tax in Interim Periods

The Company records its tax provision or benefit on an interim basis using an estimated annual effective tax rate. This rate is applied to the current period ordinary income or loss to determine the income tax provision or benefit allocated to the interim period. Losses from jurisdictions for which no benefit can be recognized and the income tax effects of unusual or infrequent items are excluded from the estimated annual effective tax rate and are recognized in the impacted interim period as discrete items. During the nine months ended June 30, 2011, the Company recognized as discrete items net tax benefits of $30 million, including $23 million from the repatriation of high tax dividends in response to changes in U.S. tax legislation and $7 million principally from the renewal of the U.S. research and experimentation credit, China investment tax credits and net tax settlements and releases.

Valuation allowances are provided against a variety of deferred tax assets including net operating loss, foreign tax credit and other tax credit carryforwards where management believes that the Company has a 50% or less chance of utilizing the associated benefit in the future. Changes in valuation allowances may impact the annual estimated tax rate, the interim period as a discrete item, or both. The estimated annual effective tax rate may also be significantly impacted by nondeductible expenses, and the Company's projected earnings mix by tax jurisdiction. Adjustments to the estimated annual effective income tax rate are recognized in the period when such estimates are revised.

Inventory Valuation

The cost of most raw materials, work in process and finished goods inventories in the U.S. is determined by the last-in, first-out ("LIFO") method. Had the Company used the first-in, first-out ("FIFO") method instead of the LIFO method for such inventories, the value of those inventories would have been $112 million higher as of June 30, 2011 and $98 million higher as of September 30, 2010. The cost of other U.S. and all non-U.S. inventories is determined using the average cost method or the FIFO method.

During the three and nine months ended June 30, 2011 and 2010, inventory quantities were reduced at the Company's U.S. Supermetals site resulting in a liquidation of LIFO layers. This had the following effects on cost of sales and net income:


	Three months ended				Nine months ended
	June 30				June 30
	2011		2010		2011		2010
	(Dollars in millions, except per share amounts)
Decrease in cost of sales	$	6	$	8	$	20	$	15
Increase in net income	$	4	$	5	$	13	$	9
Increase in net income per diluted common share	$	0.06	$	0.08	$	0.20	$	0.15

Cabot reviews inventory for both potential obsolescence and potential declines in anticipated selling prices. In this review, the Company makes assumptions about the future demand for and market value of the inventory, and based on these assumptions estimates the amount of any obsolete, unmarketable, slow moving or overvalued inventory. Cabot writes down the value of these inventories by an amount equal to the difference between the cost of the inventory and its estimated market value. There were no significant write-downs in either the three or nine months ended June 30, 2011 or 2010.

Goodwill And Other Intangible Assets

9 Months Ended

Jun. 30, 2011

Goodwill And Other Intangible Assets

Goodwill And Other Intangible Assets

C. Goodwill and Other Intangible Assets

The carrying amount of goodwill attributable to each reporting unit with goodwill balances for the periods ended June 30, 2011 and September 30, 2010, are as follows:


	Rubber Blacks		Fumed Metal Oxides		Security Materials		Total
	(Dollars in millions)
Balance at September 30, 2010	$	27	$	11	$	1	$	39
Foreign currency translation adjustment and other		—		1		1		2

Balance at June 30, 2011	$	27	$	12	$	2	$	41

Impairment tests are performed at least annually. The Company performed its annual impairment assessment as of March 31, 2011 and determined that there was no impairment.

During the current year Cabot reassessed the goodwill reporting units due to the recent acquisition of Oxonica Materials Inc. (now renamed Cabot Security Materials Inc.) from Oxonica Plc. As a result of this reassessment, the New Business Segment was split into separate reporting units, and Security Materials was identified as carrying the goodwill balance previously held by the New Business Segment.

Cabot does not have any indefinite-lived intangible assets. Cabot had $4 million of finite-lived intangible assets as of both June 30, 2011 and September 30, 2010. Intangible assets are amortized over their estimated useful lives, which range from six to fourteen years, with a weighted average period of ten years. Amortization relative to these intangible assets is expected to aggregate to less than $1 million per year over the next five years

The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss.

Employee Benefit Plans

9 Months Ended

Jun. 30, 2011

Employee Benefit Plans

Employee Benefit Plans

D. Employee Benefit Plans

Curtailment of employee benefit plan

During the first nine months of fiscal 2011, the Company incurred a curtailment in one of its foreign employee benefit plans as a result of an action initiated as part of the 2009 Global Restructuring Plan as discussed in Note H. Associated with this curtailment, the Company recognized a $1 million benefit in the first nine months of fiscal 2011.

Net periodic defined benefit pension and other postretirement benefit costs

Net periodic defined benefit pension and other postretirement benefit costs include the following:


	Three Months Ended June 30
	2011						2010						2011					2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Service cost	$	1		$	2		$	1		$	1		$	—		$	—	$	1		$	—
Interest cost		2			2			2			2			1			—		1			—
Expected return on plan assets		(2	)		(3	)		(3	)		(3	)		—			—		—			—
Amortization of prior service credit		—			—			—			—			—			—		(1	)		—
Amortization of actuarial loss		—			—			—			1			—			—		—			—

Net periodic benefit cost	$	1		$	1		$	—		$	1		$	1		$	—	$	1		$	—


	Nine Months Ended June 30
	2011						2010						2011					2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Service cost	$	3		$	5		$	3		$	4		$	1		$	—	$	1		$	—
Interest cost		6			6			6			7			3			—		3			—
Expected return on plan assets		(6	)		(9	)		(7	)		(9	)		—			—		—			—
Amortization of prior service credit		—			—			—			—			(2	)		—		(3	)		—
Amortization of actuarial loss		—			2			—			2			—			—		—			—
Curtailment income		—			(1	)		—			—			—			—		—			—

Net periodic benefit cost	$	3		$	3		$	2		$	4		$	2		$	—	$	1		$	—

Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5, 6, 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 158
-Paragraph 4, 7, 16, 20, 21
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6930749&loc=d3e4179-114921

Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e2417-114920

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 132R
-Paragraph 5
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Commitments And Contingencies

Commitments And Contingencies

9 Months Ended

Jun. 30, 2011

Commitments And Contingencies

E. Commitments and Contingencies

Purchase Commitments

Cabot has entered into long-term purchase agreements primarily for the purchase of raw materials. Under certain of these agreements, the quantity of material being purchased is fixed, but the price paid changes as market prices change. For those commitments, the amounts included in the table below are based on market prices at June 30, 2011.


	Payments Due by Fiscal Year
	Remainder of fiscal 2011		2012		2013		2014		2015		Thereafter		Total
	(Dollars in millions)
Core Segment:
Rubber Blacks Business	$	79	$	241	$	210	$	163	$	160	$	1,240	$	2,093
Supermetals Business		1		19		13		6		—		—		39
Performance Segment		4		17		29		30		30		302		412
New Business Segment		—		1		1		—		—		—		2

Total	$	84	$	278	$	253	$	199	$	190	$	1,542	$	2,546

Guarantee Agreements

Cabot has provided certain indemnities pursuant to which it may be required to make payments to an indemnified party in connection with certain transactions and agreements. In connection with certain acquisitions and divestitures, Cabot has provided routine indemnities with respect to such matters as environmental, tax, insurance, product and employee liabilities. In connection with various other agreements, including service and supply agreements, Cabot has provided routine indemnities for certain contingencies and routine warranties. Cabot is unable to estimate the maximum potential liability for these types of indemnities as a maximum obligation is not explicitly stated in most cases and the amounts, if any, are dependent upon the outcome of future contingent events, the nature and likelihood of which cannot be reasonably estimated. The duration of the indemnities vary, and in many cases are indefinite. Cabot has not recorded any liability for these indemnities in the consolidated financial statements, except as otherwise disclosed.

Contingencies

Cabot is a defendant, or potentially responsible party, in various lawsuits and environmental proceedings wherein substantial amounts are claimed or at issue.

Environmental Matters

As of June 30, 2011 and September 30, 2010, Cabot had $6 million on both a discounted and undiscounted basis and $7 million on both a discounted and undiscounted basis, respectively, reserved for environmental matters primarily related to divested businesses. These amounts represent Cabot's best estimates of its share of costs likely to be incurred at those sites where costs are reasonably estimable based on its analysis of the extent of clean up required, alternative cleanup methods available, abilities of other responsible parties to contribute and its interpretation of laws and regulations applicable to each site. Cabot reviews the adequacy of this reserve as circumstances change at individual sites. Cash payments related to these environmental matters were $2 million and $1 million in the first nine months of fiscal 2011 and 2010, respectively.

Other Matters

Respirator Liabilities

Cabot has exposure in connection with a safety respiratory products business that a subsidiary acquired from American Optical Corporation ("AO") in an April 1990 asset purchase transaction. The subsidiary manufactured respirators under the AO brand and disposed of that business in July 1995. In connection with its acquisition of the business, the subsidiary agreed, in certain circumstances, to assume a portion of AO's liabilities, including costs of legal fees together with amounts paid in settlements and judgments, allocable to AO respiratory products used prior to the 1990 purchase by the Cabot subsidiary. As more fully described in the 2010 10-K, the respirator liabilities involve claims for personal injury, including asbestosis, silicosis and coal worker's pneumoconiosis, allegedly resulting from the use of AO respirators that are alleged to have been negligently designed or labeled.

As of June 30, 2011 and September 30, 2010, there were approximately 43,000 and 45,000 claimants, respectively, in pending cases asserting claims against AO in connection with respiratory products. Cabot has a reserve to cover its expected share of liability for existing and future respirator liability claims. The book value of the reserve is being accreted up to the undiscounted liability through interest expense over the expected cash flow period, which is through 2062. At June 30, 2011 and September 30, 2010, the reserve was $12 million and $15 million, respectively, on a discounted basis ($17 million and $20 million on an undiscounted basis, respectively). Cash payments related to this liability were $3 million and $1 million in the first nine months of fiscal 2011 and 2010, respectively.

Other

During the nine months ended June 30, 2011, the Company recognized a benefit of approximately $9 million related to a legal judgment associated with a feedstock pipeline breakage that occurred in a prior period. This benefit was recorded within cost of sales and other (expense) income in the consolidated statements of operations.

The Company has various other lawsuits, claims and contingent liabilities arising in the ordinary course of its business and with respect to the Company's divested businesses. In the opinion of the Company, although final disposition of some or all of these other suits and claims may impact the Company's financial statements in a particular period, they should not, in the aggregate, have a material adverse effect on the Company's financial position.

The entire disclosure for commitments and contingencies.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
-Paragraph 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10, 11, 12
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6952336&loc=d3e14435-108349

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-Name Accounting Standards Codification
-Topic 460
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-Topic 825
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-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6449706&loc=d3e16207-108621

Income Tax Uncertainties

9 Months Ended

Jun. 30, 2011

Income Tax Uncertainties

Income Tax Uncertainties

F. Income Tax Uncertainties

As of June 30, 2011, the total amount of unrecognized tax benefits was $73 million, of which $47 million was recorded in the Company's consolidated balance sheet and $26 million, principally related to certain net operating loss carryforwards, was not recorded. In addition, accruals of $5 million and $15 million have been recorded for penalties and interest, respectively, as of June 30, 2011.

A reconciliation of the beginning and ending total amounts of unrecognized tax benefits for the nine months ended June 30, 2011 and 2010 is as follows:


	Nine months ended June 30
	2011			2010
	(Dollars in millions)
Balance at beginning of the period	$	75		$	81
Additions based on tax positions related to the current year		2			5
Additions based on tax positions of prior years		2			1
Reduction for tax positions of prior years		(6	)		(14	)

Balance at end of the period	$	73		$	73

If the unrecognized tax benefits of $73 million were recognized at a given point in time, there would be approximately a $36 million favorable impact on the Company's tax provision as a portion of the amount recognized would create a deferred tax asset which would attract a full valuation allowance based on the Company's current assessment of recoverability.

During the first nine months of fiscal 2011, the balance of unrecognized tax benefits was reduced by $6 million primarily due to the settlement of audits in a number of tax jurisdictions including a settlement recorded in income from discontinued operations, net of tax in the consolidated statement of operations. Certain Cabot subsidiaries are under audit in jurisdictions outside of the U.S. In addition, certain statutes of limitations are scheduled to expire in the near future. It is reasonably possible that a further change in the unrecognized tax benefits may occur within the next twelve months related to the settlement of one or more of these audits or the lapse of applicable statutes of limitations; however, an estimated range of the impact on the unrecognized tax benefits cannot be quantified at this time.

Cabot files U.S. federal and state and non-U.S. income tax returns in jurisdictions with varying statutes of limitations. The 2007 through 2011 tax years generally remain subject to examination by the IRS and the 2004 through 2011 tax years remain subject to examination by most state tax authorities. In significant non-U.S. jurisdictions, the 2002 through 2011 tax years generally remain subject to examination by their respective tax authorities. Cabot's significant non-U.S. jurisdictions include Argentina, Brazil, Canada, China, Germany, Japan, the Netherlands, and the United Kingdom.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 08
-Paragraph h
-Article 4

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 136, 172
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 109
-Paragraph 43, 44, 45, 46, 47, 48, 49
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Earnings Per Share

9 Months Ended

Jun. 30, 2011

Earnings Per Share

Earnings Per Share

G. Earnings Per Share

The following tables summarize the components of the basic and diluted earnings per common share computations:


	Three Months Ended June 30					Nine Months Ended June 30
	2011		2010			2011			2010
	(Dollars and shares in millions, except per share amounts)
Basic EPS:
Net income attributable to Cabot Corporation	$	60	$	47		$	186		$	119
Less: Dividends and dividend equivalents to participating securities		—		—			1			1
Less: Undistributed earnings allocated to participating securities⁽¹⁾		—		1			2			2

Earnings allocated to common shareholders (numerator)	$	60	$	46		$	183		$	116

Weighted average common shares outstanding		65.4		65.3			65.4			65.3
Less: Participating securities⁽¹⁾		0.7		1.4			0.8			1.6

Adjusted weighted average common shares (denominator)		64.7		63.9			64.6			63.7


Basic EPS	$	0.93	$	0.72		$	2.84		$	1.82


Diluted EPS:
Earnings allocated to common shareholders	$	60	$	46		$	183		$	116
Plus: Earnings allocated to participating securities		—		1			3			3
Less: Adjusted earnings allocated to participating securities⁽²⁾		—		(1	)		(3	)		(3	)

Earnings allocated to common shareholders (numerator)	$	60	$	46		$	183		$	116

Adjusted weighted average common shares outstanding		64.7		63.9			64.6			63.7
Effect of dilutive securities:
Common shares issuable⁽³⁾		0.9		0.6			0.8			0.5

Adjusted weighted average common shares (denominator)		65.6		64.5			65.4			64.2


Diluted EPS	$	0.92	$	0.72		$	2.81		$	1.81

⁽¹⁾	Participating securities consist of shares of unvested restricted stock, vested restricted stock awards held by employees in which Cabot has a security interest, and unvested time-based restricted stock units.

Undistributed earnings are the earnings which remain after dividends declared during the period are assumed to be distributed to the common and participating shareholders. Undistributed earnings are allocated to common and participating shareholders on the same basis as dividend distributions. The calculation of undistributed earnings is as follows:


	Three Months Ended June 30				Nine Months Ended June 30
	2011		2010		2011		2010
	(Dollars in millions)
Calculation of undistributed earnings:
Net income attributable to Cabot Corporation	$	60	$	47	$	186	$	119
Less: Dividends declared on common stock		11		12		34		34
Less: Dividends declared on participating securities		—		—		1		1

Undistributed earnings	$	49	$	35	$	151	$	84

Allocation of undistributed earnings:
Undistributed earnings allocated to common shareholders	$	49	$	34	$	149	$	82
Undistributed earnings allocated to participating shareholders		—		1		2		2

Undistributed earnings	$	49	$	35	$	151	$	84

⁽²⁾	Undistributed earnings are adjusted for the assumed distribution of dividends to the dilutive securities, which are described in (3) below, and then reallocated to participating securities.

⁽³⁾

Represents incremental shares of common stock from the (i) assumed exercise of stock options issued under Cabot's equity incentive plans; (ii) assumed issuance of shares to employees pursuant to the Company's Supplemental Retirement Savings Plan; and (iii) assumed issuance of shares under outstanding performance-based stock unit awards issued under Cabot's equity incentive plans. For the three and nine months ended June 30, 2011, 121,000 and 271,000 incremental shares of common stock, respectively, were not included in the calculation of diluted earnings per share because the inclusion of these shares would have been anti-dilutive. For both the three and nine months ended June 30, 2010, 206,000 incremental shares of common stock were not included in the calculation of diluted earnings per share because the options' exercise prices were greater than the average market price of Cabot common stock for the relevant period.

Restructuring

9 Months Ended

Jun. 30, 2011

Restructuring

Restructuring

H. Restructuring

Cabot's restructuring activities were recorded in the consolidated statements of operations as follows:


	Three Months Ended June 30				Nine Months Ended June 30
	2011		2010		2011		2010
	(Dollars in millions)
Cost of sales	$	5	$	12	$	15	$	23
Selling and administrative expenses		—		2		1		15

Total	$	5	$	14	$	16	$	38

Details of these restructuring activities and the related reserves during the three months ended June 30, 2011 are as follows:


	Severance and Employee Benefits			Environmental Remediation			Asset Impairment and Accelerated Depreciation			Other			Total
	(Dollars in millions)
Reserve at March 31, 2011	$	14		$	2		$	—		$	1		$	17
Charges		2			1			1			1			5
Costs charged against assets/liabilities		—			—			(1	)		—			(1	)
Cash paid		(3	)		(2	)		—			(1	)		(6	)

Reserve at June 30, 2011	$	13		$	1		$	—		$	1		$	15

Details of these restructuring activities and the related reserves during the nine months ended June 30, 2011 are as follows:


	Severance and Employee Benefits			Environmental Remediation			Asset Impairment and Accelerated Depreciation			Other			Total
	(Dollars in millions)
Reserve at September 30, 2010	$	18		$	1		$	—		$	—		$	19
Charges		6			2			4			4			16
Costs charged against assets / liabilities		—			—			(4	)		1			(3	)
Cash paid		(12	)		(2	)		—			(4	)		(18	)
Foreign currency translation adjustment		1			—			—			—			1

Reserve at June 30, 2011	$	13		$	1		$	—		$	1		$	15

Closure of Grigno, Italy Manufacturing Facility and Other Activities

In February 2011, the Company ceased manufacturing operations at its thermoplastic concentrates facility in Grigno, Italy. This decision was made to align Cabot's manufacturing capabilities with the market outlook and Cabot's Performance Segment strategy. The closure, which affected 37 employees, resulted in $6 million of charges to earnings and is comprised of $3 million for severance and employee benefits and $3 million for accelerated depreciation and asset impairments.

Through June 30, 2011, Cabot made $1 million of cash payments associated with this restructuring plan. The Company expects to make cash payments of less than $1 million during the remainder of fiscal 2011 and $2 million thereafter.

As of June 30, 2011, Cabot has $2 million of accrued restructuring costs in the consolidated balance sheet related to this site closure.

In addition, during the first nine months of fiscal 2011 Cabot recorded approximately $4 million of other severance-related restructuring charges. Cabot expects the entire $4 million to be paid in fiscal 2012.

Closure of Thane, India Manufacturing Facility

In fiscal 2010, Cabot ceased manufacturing operations at its carbon black manufacturing facility in Thane, India. This decision, which affected approximately 120 employees, was made as a result of a broad reaching analysis of the Company's manufacturing assets, including their cost structure, ability to expand and a variety of other factors. The Company continues to maintain a presence in India through its fumed metal oxides manufacturing joint venture and continuing commercial operations in carbon black and other products.

The Company expects the closure plan will result in a total pre-tax charge to earnings of approximately $20 million. Through June 30, 2011, Cabot has recorded $19 million of charges associated with this restructuring, comprised of $6 million for severance and employee benefits, $10 million for accelerated depreciation and asset impairments, $1 million for demolition and site clearing costs and $2 million for other post-closing costs. These amounts exclude any potential gain that may be realized on the sale of certain assets related to the manufacturing facility.

Net cash outlays related to this plan are expected to be approximately $8 million. Through June 30, 2011, Cabot has made cash payments of $7 million. The Company expects to make cash payments of approximately $1 million during the remainder of fiscal 2011 and thereafter. These amounts exclude any potential cash to be received on the sale of certain assets related to the manufacturing facility.

As of June 30, 2011, Cabot has $1 million of accrued restructuring costs in the consolidated balance sheet related to this site closure.

2009 Global Restructuring

In fiscal 2009, Cabot initiated its 2009 Global Restructuring Plan. Under this plan, the Company closed three of its manufacturing facilities and implemented operating cost and workforce reductions across a variety of its other operations. In fiscal 2010 the Company consolidated several of its European administrative offices in a new European headquarters office in Switzerland.

The Company expects this restructuring will result in a cumulative pre-tax charge to earnings of approximately $124 million, of which $123 million has been recorded through June 30, 2011. The total amounts the Company has recorded for each major type of cost associated with the restructuring plan are: (i) severance and employee benefits of $55 million for approximately 400 employees, (ii) accelerated depreciation and impairment of facility assets of $48 million, net of gains associated with the sale of certain assets, (iii) demolition and site clearing costs of $5 million, and (iv) other post-closing costs of $15 million. Net cash outlays related to these actions are expected to be approximately $69 million. Through June 30, 2011, Cabot has made net cash payments of $65 million. The Company expects to make net cash payments of approximately $4 million during the remainder of fiscal 2011 and thereafter.

As of June 30, 2011, Cabot has $8 million of restructuring costs in accrued expenses in the consolidated balance sheet related to this plan.

The entire disclosure for restructuring and related activities. Description of restructuring activities such as exit and disposal activities, include facts and circumstances leading to the plan, the expected plan completion date, the major types of costs associated with the plan activities, total expected costs, the accrual balance at the end of the period, and the periods over which the remaining accrual will be settled.

Fair Value Measurements

9 Months Ended

Jun. 30, 2011

Fair Value Measurements

Fair Value Measurements

I. Fair Value Measurements

The FASB authoritative guidance on fair value measurements defines fair value, establishes a framework for measuring fair value in generally accepted accounting principles, and expands disclosures about fair value measurements. The disclosures focus on the inputs used to measure fair value. The guidance establishes the following hierarchy for categorizing these inputs:


Level 1	—	Quoted market prices in active markets for identical assets or liabilities

Level 2	—	Significant other observable inputs (e.g., quoted prices for similar items in active markets, quoted prices for identical or similar items in markets that are not active, inputs other than quoted prices that are observable such as interest rate and yield curves, and market-corroborated inputs)

Level 3	—	Significant unobservable inputs

There were no transfers between Level 1 and Level 2, or transfers into or out of Level 3, during the first nine months of either fiscal 2011 or 2010.

The following table presents information about the Company's financial assets and liabilities measured at fair value on a recurring basis as of June 30, 2011 and September 30, 2010. The derivatives presented in the table below are presented by derivative type, net of the legal right to offset derivative settlements by each counterparty:


	June 30, 2011		September 30, 2010
	Level 2 Inputs		Level 2 Inputs
	(Dollars in millions)
Assets at fair value:
Guaranteed investment contract⁽¹⁾	$	15	$	14
Derivatives relating to:
Interest rates⁽²⁾		3		5
Foreign currency⁽²⁾		1		—

Total assets at fair value	$	19	$	19

Liabilities at fair value:
Derivatives relating to: Foreign currency⁽²⁾	$	50	$	42

Total liabilities at fair value	$	50	$	42

⁽¹⁾	Included in "Other assets" in the consolidated balance sheets.

⁽²⁾	Included in "Prepaid expenses and other current assets", "Other assets", "Accounts payable and accrued liabilities" or "Other liabilities" in the consolidated balance sheets.

During the three and nine months ended June 30, 2011, there was no change to assets measured at fair value on a nonrecurring basis. Additionally, there was no change to assets measured at fair value on a nonrecurring basis during the three months ended June 30, 2010. However, during the nine months ended June 30, 2010, Cabot's management concluded that the carrying value of land related to a former carbon black location exceeded its fair value of $6 million based on a comparison of similar facilities in the region. Accordingly, the Company recorded an impairment charge of $2 million within cost of sales in the consolidated statement of operations to write this land down to its $6 million fair value during the nine months ended June 30, 2010. The value of the land is included in other assets in the consolidated balance sheet.

Tabular disclosure of the fair value measurement of assets and liabilities which includes [financial] instruments measured at fair value that are classified in stockholders' equity. Such assets and liabilities may be measured on a recurring or nonrecurring basis. The disclosures which may be required or desired include: (1) for assets and liabilities measured on a recurring basis, disclosure may include: (a) the fair value measurements at the reporting date; (b) the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3); (c) for fair value measurements using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (i) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (ii) purchases, sales, issuances, and settlements (net); (iii) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs); (d) the amount of the total gains or losses for the period in subparagraph (c) (i) above included in earnings (or changes in net assets) that are attributable to the change in unrealized gains or losses relating to those assets and liabilities still held at the reporting date and a description of where those unrealized gains or losses are reported in the statement of income (or activities); (e) the valuation technique(s) used to measure fair value and a discussion of changes in valuation techniques, if any, during the period and (2) for assets and liabilities that are measured at fair value on a nonrecurring basis (for example, impaired assets) disclosure may include, in addition to (a) above: (a) the reasons for the fair value measurements recorded; (b) the same as (b) above; (c) for fair value measurements using significant unobservable inputs (Level 3), a description of the inputs and the information used to develop the inputs; and (d) the valuation technique(s) used to measure fair value and a discussion of changes, if any, in the valuation technique(s) used to measure similar assets and/or liabilities in prior periods. Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset.

Fair Value Of Financial Instruments

Fair Value Of Financial Instruments

9 Months Ended

Jun. 30, 2011

Fair Value Of Financial Instruments

J. Fair Value of Financial Instruments

The carrying amounts and fair values of the Company's financial instruments at June 30, 2011 and September 30, 2010 are as follows:


	June 30, 2011				September 30, 2010
	Carrying		Fair		Carrying		Fair
	Amount		Value		Amount		Value
	(Dollars in millions)
Assets:
Cash and cash equivalents	$	344	$	344	$	387	$	387
Accounts and notes receivable		697		697		576		576
Derivative instruments		1		1		2		2
Liabilities:
Notes payable to banks		61		61		29		29
Accounts payable and accrued liabilities		429		429		447		447
Long-term debt—fixed rate		582		631		604		661
Long-term debt—floating rate		18		18		16		16
Capital lease obligations		4		4		3		3
Derivative instruments		47		47		39		39

At June 30, 2011 and September 30, 2010, the fair values of cash and cash equivalents, accounts and notes receivable, accounts payable and accrued liabilities, and notes payable to banks approximated carrying values due to the short-term nature of these instruments. The estimated fair values of derivative instruments are valued as described in Note I. The fair value of Cabot's fixed rate long-term debt and capital lease obligations are estimated based on comparable quoted market prices at the respective period ends. The carrying amount of Cabot's floating rate long-term debt approximates its fair value.

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44A, 44B
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15C, 15D
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15A
-Subparagraph a-d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 15B
-Subparagraph a, b
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 3, 10, 14, 15
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32, 33, 34
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 159
-Paragraph 17-22, 27, 28
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13537-108611

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13433-108611

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14172-108612

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13504-108611

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19296-110258

Financial Instruments

9 Months Ended

Jun. 30, 2011

Financial Instruments

Financial Instruments

K. Financial Instruments

Risk Management

Cabot's business operations are exposed to changes in interest rates, foreign currency exchange rates and commodity prices because Cabot finances certain operations through long- and short-term borrowings, denominates transactions in a variety of foreign currencies and purchases certain commoditized raw materials. Changes in these rates and prices may have an impact on future cash flows and earnings. The Company manages these risks through normal operating and financing activities and, when deemed appropriate, through the use of derivative financial instruments.

The Company has policies governing the use of derivative instruments and does not enter into financial instruments for trading or speculative purposes.

By using derivative instruments, Cabot is subject to credit and market risk. If a counterparty fails to fulfill its performance obligations under a derivative contract, Cabot's credit risk will equal the fair value of the derivative. Generally, when the fair value of a derivative contract is positive, the counterparty owes Cabot, thus creating a payment risk for Cabot. The Company minimizes counterparty credit (or repayment) risk by entering into transactions with major financial institutions of investment grade credit rating. As of June 30, 2011, the counterparties with which the Company has executed derivatives carried a Standard and Poor's credit rating between AA- and A+, inclusive. Cabot's exposure to market risk is not hedged in a manner that completely eliminates the effects of changing market conditions on earnings or cash flow. No significant concentration of credit risk existed at June 30, 2011.

Interest Rate Risk Management

Cabot's objective is to maintain a certain fixed-to-floating interest rate mix on the Company's debt portfolio. Cabot enters into interest rate swaps as a hedge of the underlying debt instruments to effectively change the characteristics of the interest rate without changing the debt instrument. The following table provides details of the derivatives held as of June 30, 2011 and September 30, 2010 to manage interest rate risk.


		Notional Amount
Description	Borrowing	June 30 , 2011	September 30, 2010	Hedge Designation
Interest Rate Swap—Fixed to Variable	Eurobond (20% of $175 million)	USD 35 million	USD 35 million	Fair Value
Interest Rate Swap—Fixed to Variable⁽¹⁾	Medium Term Notes	—	USD 15 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 8 million	USD 8 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value

⁽¹⁾	Cabot's interest rate swap derivative instrument and the hedged debt borrowing matured during the second quarter of fiscal 2011.

Foreign Currency Risk Management

Cabot's international operations are subject to certain risks, including currency exchange rate fluctuations and government actions. Cabot endeavors to match the currency in which debt is issued to the currency of the Company's major, stable cash receipts. In some situations Cabot has issued debt denominated in U.S. dollars and then entered into cross currency swaps that exchange the dollar principal and interest payments into a currency where the Company expects long-term, stable cash receipts.

Additionally, the Company has foreign currency exposure arising from its net investments in foreign operations. Cabot, from time to time, enters into cross-currency swaps to mitigate the impact of currency rate changes on the Company's net investments.

The Company also has foreign currency exposure arising from the denomination of current assets and current liabilities in foreign currencies other than the functional currency of a given subsidiary as well as the risk that currency fluctuations could affect the dollar value of future cash flows generated in foreign currencies. Accordingly, Cabot uses short-term forward contracts to minimize the exposure to foreign currency risk. These forward contracts typically have a duration of 30 days.

In certain situations where the Company has forecasted purchases under a long-term commitment or forecasted sales denominated in a foreign currency, Cabot may enter into appropriate financial instruments in accordance with the Company's risk management policy to hedge future cash flow exposures. The following table provides details of the derivatives held as of June 30, 2011 and September 30, 2010 to manage foreign currency risk.


		Notional Amount		Hedge Designation
Description	Borrowing	June 30, 2011	September 30, 2010	Hedge Designation
Cross Currency Swap	Eurobond (80% of $175 million)	USD 140 million swapped to EUR 124 million	USD 140 million swapped to EUR 124 million		No designation

Cross Currency Swap	Eurobond (20% of $175 million)	USD 35 million swapped to EUR 31 million	USD 35 million swapped to EUR 31 million		No designation

Forward Foreign Currency Contracts ⁽¹⁾	N/A	USD 21 million	USD 23 million		No designation

Forward Foreign Currency Contracts ⁽²⁾	N/A	JPY 1,220 million	—		Cash Flow

⁽¹⁾	Cabot's forward foreign exchange contracts are denominated primarily in the Argentine peso, Australian dollar, Brazilian real, British pound sterling, Canadian dollar, Euro, and Japanese yen.

⁽²⁾	Cabot's forward foreign exchange contracts designated as cash flow hedges were entered into during the third quarter and first nine months of fiscal 2011.

Commodity Risk Management

Certain of Cabot's carbon black plants in Europe are subject to mandatory greenhouse gas emission trading schemes. Cabot's objective is to ensure compliance with the European Union Emission Trading Scheme, which is based upon a Cap-and-Trade system that establishes a maximum allowable emission credit for each ton of CO₂ emitted. European Union Allowances ("EUA") originate from the individual EU member state's country allocation process and are issued by that country's government. A company that has an excess of EUAs based on the CO₂ emissions limits may sell EUAs in the Emission Trading Scheme and if they have a shortfall, a company can buy EUAs or Certified Emission Reduction ("CER") units to comply.

In order to limit variability in cost to Cabot's European operations, the Company committed to current prices by entering into agreements to purchase CERs and to sell EUAs, which settle each December until 2012. The following table provides details of the derivatives held as of June 30, 2011 and September 30, 2010 to manage commodity risk.

Net Buyer /
Net Seller

Notional Amount

Hedge
Designation

Description

June 30, 2011

September 30, 2010

CERs

Buyer

EUR 1 million

EUR 2 million

No designation

EUAs

Seller

EUR 1 million

EUR 2 million

No designation

Accounting for Derivative Instruments and Hedging Activities

The Company determines the fair value of financial instruments using quoted market prices whenever available. When quoted market prices are not available for various types of financial instruments (such as forwards, options and swaps), the Company uses standard models with market-based inputs, which take into account the present value of estimated future cash flows and the ability of the financial counterparty to perform.

Fair Value Hedge

For interest rate swaps designated as fair value hedges, the Company uses standard models with market-based inputs. The significant inputs to these models are interest rate curves for discounting future cash flows. For derivative instruments that are designated and qualify as fair value hedges, the gain or loss on the derivative as well as the offsetting gain or loss on the hedged item attributable to the hedged risk are recognized in current period earnings.

Cash Flow Hedge

For cross currency swaps designated as cash flow hedges, the Company uses standard models with market-based inputs. The significant inputs to these models are interest rate curves for discounting future cash flows, and exchange rate curves of the foreign currency for translating future cash flows. For derivative instruments that are designated and qualify as cash flow hedges, the effective portion of the gain or loss on the derivative is recorded in accumulated other comprehensive income and reclassified to earnings in the same period or periods during which the hedged transaction affects earnings. Gains and losses on the derivative representing either hedge ineffectiveness or hedge components excluded from the assessment of effectiveness are recognized in current period earnings.

Net Investment Hedge

For cross currency swaps designated as net investment hedges, the Company uses standard models with market-based inputs. The significant inputs to these models are interest rate curves for discounting future cash flows. For net investment hedges, changes in the fair value of the effective portion of the derivatives' gains or losses are reported as foreign currency translation gains or losses in accumulated other comprehensive income while changes in the ineffective portion are reported in earnings. The gains or losses on derivative instruments reported in accumulated other comprehensive income are reclassified to earnings in the period in which earnings are affected by the underlying item, such as a disposal or substantial liquidation of the entities being hedged.

As of June 30, 2011, there were no open derivatives designated as net investment hedges. During the first quarter of fiscal 2010, the Company's derivative instrument, which swapped $20 million to JPY 2.5 billion, matured leading to a cash settlement payment of $7 million in that period. The cumulative loss related to this net investment hedge recorded in accumulated other comprehensive income as of both June 30, 2011 and September 30, 2010 was $27 million.

Other Derivative Instruments

From time to time, the Company may enter into certain derivative instruments that may not be designated as hedges for accounting purposes. In determining the fair value of the commodity derivatives, the significant inputs to valuation models are quoted market prices of similar instruments in active markets. Although these derivatives do not qualify for hedge accounting, Cabot believes that such instruments are closely correlated with the underlying exposure, thus managing the associated risk. The gains or losses from changes in the fair value of derivative instruments that are not accounted for as hedges are recognized in current period earnings.

For the three and nine months ended June 30, 2011, for derivatives designated as hedges, the change in unrealized losses in accumulated other comprehensive income, the hedge ineffectiveness recognized in earnings and the realized gains reclassified from accumulated other comprehensive income to earnings were immaterial. For the three and nine months ended June 30, 2010, for derivatives designated as hedges, the change in unrealized gains in accumulated other comprehensive income and the hedge ineffectiveness recognized in earnings was immaterial. Additionally, during these periods, there were no gains or losses reclassified from accumulated other comprehensive income to earnings.

For the three and nine months ended June 30, 2011, gains of $3 million and $9 million, respectively, were recognized in earnings as a result of the remeasurement to Euros of the $175 million bond issued by one of Cabot's European subsidiaries. These gains, which were recognized in earnings through other (expense) income within the consolidated statement of operations, were offset by losses of $3 million and $6 million, respectively, from Cabot's cross currency swaps that are not designated as hedges, but which Cabot entered into to offset the foreign currency translation exposure on the debt. Additionally, during the three and nine months ended June 30, 2011, Cabot recognized in earnings through other (expense) income within the consolidated statement of operations gains of less than $1 million and $1 million, respectively, related to its foreign currency forward contracts, which were not designated as hedges.

For the three and nine months ended June 30, 2010, losses of $17 million and $32 million, respectively, were recognized in earnings as a result of the remeasurement to Euros of the $175 million bond issued by one of Cabot's European subsidiaries. These losses, which were recognized in earnings through other (expense) income within the consolidated statement of operations, were offset by gains of $19 million and $34 million, respectively, from Cabot's cross currency swaps that are not designated as hedges, but which Cabot entered into to offset the foreign currency translation exposure on the debt. Additionally, during the three and nine months ended June 30, 2010, Cabot recognized in earnings through other (expense) income within the consolidated statement of operations gains of $3 million and $6 million, respectively, related to its foreign currency forward contracts, which were not designated as hedges.

The following table provides the fair value and consolidated balance sheet presentations of derivative instruments by each derivative type, without regard to the legal right to offset derivative settlement by each counterparty:


	Consolidated Balance Sheet Caption	June 30, 2011		September 30, 2010
		(Dollars in millions)
Fair Value of Derivative Instruments
Asset Derivatives
Derivatives designated as hedges
Interest rate⁽¹⁾	Prepaid expenses and other current assets, Other assets, and Other liabilities	$	3	$	5

Total derivatives designated as hedges		$	3	$	5

Derivatives not designated as hedges
Foreign currency	Prepaid expenses and other current assets	$	1	$	—
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	2	$	2

Total Asset Derivatives		$	5	$	7

Liability Derivatives
Derivatives not designated as hedges
Foreign currency⁽¹ ⁾	Accounts payable and accrued liabilities, and Other liabilities	$	50	$	42
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	51	$	44

Total Liability Derivatives		$	51	$	44

⁽¹⁾	Contracts of $3 million and $4 million presented on a gross basis in this table at June 30, 2011 and September 30, 2010, respectively, have the legal right to offset against other types of contracts with a common counterparty and, therefore, are presented on a net basis in noncurrent "Other liabilities" in the consolidated balance sheet.
⁽²⁾	Contracts in an asset and liability position presented on a gross basis in this table have the legal right of offset and, therefore, are presented on a net basis in "Prepaid expenses and other current assets" and noncurrent "Other assets" in the consolidated balance sheet.

See Note I "Fair Value Measurements" for classification of derivatives by input level. The net after-tax amounts to be reclassified from accumulated other comprehensive income to earnings within the next 12 months are expected to be immaterial.

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 107
-Paragraph 10
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Financial Information By Segment

Venezuela

9 Months Ended

Jun. 30, 2011

Venezuela

Venezuela

L. Venezuela

Overview

Cabot owns 49% of an operating affiliate in Venezuela, which is accounted for as an equity affiliate, through wholly owned subsidiaries that carry the investment and receive its dividends. As of June 30, 2011, these subsidiaries carried the operating affiliate investment of $25 million and held 21 million bolivars ($5 million) in cash and dividends receivable.

The following provides a synopsis of recent currency related events in Venezuela and their impact on Cabot's financial statements:

Fourth quarter fiscal 2009

Continued political and economic uncertainty in Venezuela led Cabot to decide in the fourth quarter of fiscal 2009 to repatriate the majority of the Company's cash from its Venezuelan subsidiaries using several available mechanisms, as exchange through the Venezuelan central bank ("CADIVI") process was uncertain. Cabot remeasured any remaining bolivar denominated cash balances and bolivar denominated dividends receivable held in its subsidiaries using the parallel rate at the end of the reporting period, which was 5.55 bolivars to the U.S. dollar ("B/$") as of September 30, 2009. This was necessary as it was Cabot's intention to repatriate those monies as soon as practicable and Cabot believed that the official exchange rate sanctioned by the Venezuelan government would not be available to the Company for the purpose of dividend repatriation. This remeasurement resulted in a $6 million charge through other income (expense) within the consolidated statement of operations in the fourth quarter of fiscal 2009. This repatriation was completed in the first quarter of fiscal 2010.

Second quarter of fiscal 2010

In January 2010, the Venezuelan government announced a devaluation of the bolivar from 2.15 B/$ to two official rates through CADIVI, an essentials rate at 2.60 B/$ and a non-essentials rate at 4.30 B/$. The latter rate is the rate that Cabot believes would continue to be available to the operating affiliate to transact its ordinary activities. Given that Cabot had determined, as of January 1, 2010, that the Venezuelan economy was highly inflationary, as of the second quarter of fiscal 2010 Cabot began to remeasure all transactions of the operating affiliate denominated in bolivars to U.S. dollars using the non-essentials rate of 4.30 B/$. This decision gave rise to a gain of $1 million in Cabot's second quarter of fiscal 2010, because of the net monetary liability position of the operating affiliate. Additionally, Cabot recognized a tax benefit from a reduction in the Company's deferred tax liability based on the impact of the devaluation of the bolivar on the unremitted earnings pool. Accordingly, Cabot recorded a one-time benefit of $2 million in the second quarter of fiscal 2010. The parallel market (which was transacting at 7.00 B/$ as of March 31, 2010) continued to be operational for repatriation transactions, and accordingly drove the remeasurement rate of the bolivar denominated monetary assets held by Cabot's subsidiaries.

Third quarter of fiscal 2010

In May 2010, the Venezuelan government eliminated the use of the parallel market, and subsequently established an officially sanctioned and regulated secondary market. This market, "SITME", which effectively transacts at 5.30 B/$, operates in addition to the two official CADIVI rates, and is subject to restrictions which preclude Cabot from utilizing this market to remit dividends.

As of June 30, 2010 Cabot's subsidiaries held 5 million bolivars in cash (from dividends paid), and 8 million bolivars in dividends receivable from the operating affiliate. However, with the closure of the parallel market, Cabot no longer has a mechanism by which it may convert and remit these bolivar holdings. Accordingly Cabot remeasured the bolivar denominated cash and dividends receivable at the CADIVI non-essentials rate of 4.30 B/$, resulting in the recognition of a $1 million gain in the third quarter of fiscal 2010 through other expense within the consolidated statement of operations.

Fourth quarter of fiscal 2010

There were no opportunities to convert the subsidiaries' bolivars through Venezuelan government, or government backed, bond offerings during the fourth quarter of fiscal 2010. The bolivar denominated assets held by the subsidiaries were valued at approximately $3 million as of September 30, 2010.

First quarter of fiscal 2011

In late October 2010, the Company participated in a bond offering, repatriating approximately 4 million bolivars at a rate of 6.57 B/$, which resulted in an exchange loss of less than $1 million, recognized in the first quarter of fiscal 2011. While this indicates that there continue to be some government sanctioned processes available to convert bolivars to U.S. dollars at amounts other than the CADIVI or SITME rates, as management believes these processes do not constitute active markets, the Company continues to use the CADIVI official rate of 4.30 B/$ to remeasure its bolivar balances. Cabot still intends to convert substantially all bolivars held by the Venezuelan subsidiaries to U.S. dollars as soon as practical and continues to monitor for opportunities to convert its bolivars through Venezuelan government, or government backed, bond offerings.

During the first quarter of fiscal 2011, the operating affiliate paid a dividend of 15 million bolivars to the subsidiaries, bringing the balance of bolivar denominated cash and dividends receivable held by the subsidiaries as of December 31, 2010 to 20 million bolivars.

Second quarter of fiscal 2011

On January 1, 2011 the essentials exchange rate was increased from 2.60 B/$ to 4.30 B/$, making the essentials rate equal to the non-essentials rate. This change does not impact Cabot's consolidation of the entity as the entity uses the non-essentials rate to remeasure its transactions. However, the increase in the essentials rate may result in increased feedstock costs to the operating affiliate, which could impact sales volumes or margins.

During the second quarter of fiscal 2011, the operating affiliate paid a dividend of 1 million bolivars to the subsidiaries, bringing the balance of bolivar denominated cash and dividends receivable held by the subsidiaries as of March 31, 2011 to 21 million bolivars.

Third quarter of fiscal 2011

During the third quarter of fiscal 2011, the operating affiliate declared a dividend of 4 million bolivars to the subsidiaries, and paid the dividend in USD using an exchange rate of 4.30 B/$.

Any future change in the CADIVI official rate or opening of additional parallel markets could lead the Company to use a different B/$ exchange rate and result in gains or losses on the bolivar denominated assets held by Cabot's subsidiaries, which are valued at approximately $5 million as of June 30, 2011.

While the events relating to the parallel market, and official exchange rate movements did not have a material impact on Cabot's operating affiliate, the Company continues to monitor developments in Venezuela and their potential impact on the operating affiliate. Cabot uses a discounted cash flow model to determine if investments are impaired when triggering events such as changes in the business environment occur. Critical considerations of the model include the profitability of the operating affiliate and Cabot's ability to repatriate the affiliate's earnings. Based on the profitability of the operating affiliate and uncertainty concerning the continuation of the current currency restrictions, as evidenced by the successful third quarter remittance of dividends, Cabot does not believe that the investment in the operating affiliate is impaired.

Financial Information By Segment

9 Months Ended

Jun. 30, 2011

Financial Information By Segment

M. Financial Information by Segment

Cabot is organized into four business segments: the Core Segment, which is further disaggregated for financial reporting purposes into the Rubber Blacks and Supermetals Businesses, the Performance Segment, the New Business Segment and the Specialty Fluids Segment. While the Chief Operating Decision Maker uses a number of performance measures to manage the performance of the segments and allocate resources to them, segment earnings before interest and taxes ("segment EBIT") is the measure that is most consistently used and is, therefore, the measure presented for each segment in the table below on the line entitled "Income (loss) before taxes".


	Core Segment
	Rubber Blacks Business		Supermetals Business		Performance Segment		New Business Segment			Specialty Fluids Segment		Segment Total		Unallocated and Other			Consolidated Total
	(Dollars in millions)
Three months ended June 30, 2011
Net sales and other operating revenues⁽¹⁾	$	531	$	47	$	240	$	30		$	12	$	860	$	23		$	883
Income (loss) before taxes⁽²⁾	$	50	$	19	$	42	$	1		$	3	$	115	$	(32	)	$	83
Three months ended June 30, 2010
Net sales and other operating revenues⁽¹⁾	$	437	$	47	$	200	$	25		$	22	$	731	$	22		$	753
Income (loss) before taxes⁽²⁾	$	41	$	14	$	35	$	—		$	11	$	101	$	(31	)	$	70
Nine months ended June 30, 2011
Net sales and other operating revenues⁽¹⁾	$	1,436	$	158	$	652	$	77		$	42	$	2,365	$	62		$	2,427
Income (loss) before taxes⁽²⁾	$	138	$	61	$	109	$	(1	)	$	10	$	317	$	(92	)	$	225
Nine months ended June 30, 2010
Net sales and other operating revenues⁽¹⁾	$	1,247	$	128	$	587	$	64		$	52	$	2,078	$	66		$	2,144
Income (loss) before taxes⁽²⁾	$	122	$	23	$	101	$	(2	)	$	21	$	265	$	(108	)	$	157

⁽¹⁾	Unallocated and Other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.

⁽²⁾

Unallocated and Other includes certain items and eliminations that are not allocated to the operating segments. Management does not consider these items necessary for an understanding of the operating results of these segments and such amounts are excluded in the segment reporting to the Chief Operating Decision Maker. Income (loss) from continuing operations before taxes that are categorized as Unallocated and Other includes:


	Three Months Ended June 30						Nine Months Ended June 30
	2011			2010			2011			2010
	(Dollars in millions)
Interest expense	$	(9	)	$	(10	)	$	(29	)	$	(30	)
Certain items^(a)		(5	)		(15	)		(16	)		(41	)
Equity in net income of affiliated companies^(b)		(2	)		(1	)		(6	)		(5	)
Unallocated corporate costs^(c)		(12	)		(9	)		(35	)		(30	)
Foreign currency transactions and other (losses) income, net^(d)		(4	)		4			(6	)		(2	)

Total	$	(32	)	$	(31	)	$	(92	)	$	(108	)

^(a)

Certain items are items that management does not consider to be representative of segment results and they are, therefore, excluded from segment EBIT. Certain items for both three and nine months ended June 30, 2011 primarily include charges for global restructuring activities discussed in Note H. Certain items for the three months ended June 30, 2010 include charges of $14 million related to the global restructuring activities discussed in Note H as well as $1 million related to environmental reserves and legal settlements. Certain items for the first nine months of fiscal 2010 include $38 million related to global restructuring activities, a $2 million long-lived asset impairment of land related to a former carbon black site, and $2 million for environmental reserves and legal settlements. These charges were partially offset by $1 million recovered from an investment previously impaired.

^(b)	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and Other to reconcile to segment EBIT.

^(c)	Unallocated corporate costs are not controlled by the segments and primarily benefit corporate interests.

^(d)

Foreign currency transactions and other (losses) income, net consists principally of gains (losses) arising from foreign currency transactions, net of other foreign currency risk management activities, and the profit related to the corporate adjustment for unearned revenue. Additionally, for both the three and nine months ended June 30, 2011, this amount included a $3 million charge related to a change in the net worth tax regulations in Colombia. For the nine months ended June 30, 2011, this amount also includes $3 million related to a portion of the benefit from a legal judgment.

The Performance Segment is comprised of the Performance Products and Fumed Metal Oxides Businesses. The net sales from each of these businesses for the three and nine months ended June 30, 2011 and 2010 are as follows:


	Three Months Ended				Nine Months Ended
	June 30				June 30
	2011		2010		2011		2010
	(Dollars in millions)
Performance Products	$	173	$	137	$	464	$	401
Fumed Metal Oxides		67		63		188		186

Total Performance Segment Sales	$	240	$	200	$	652	$	587

The New Business Segment is comprised of the Inkjet Colorants and the Aerogel Businesses and the business development activities of Cabot Superior MicroPowders. The net sales from each of these businesses for the three and nine months ended June 30, 2011 and 2010 are as follows:


	Three Months Ended				Nine Months Ended
	June 30				June 30
	2011		2010		2011		2010
	(Dollars in millions)
Inkjet colorants	$	20	$	15	$	50	$	43
Aerogel		8		8		19		16
Superior MicroPowders		2		2		8		5

Total New Business Segment Sales	$	30	$	25	$	77	$	64

Tabular disclosure of the profit or loss and total assets for each reportable segment. An entity discloses certain information on each reportable segment if the amounts (a) are included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) are otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.

Revenue Recognition And Accounts Receivable

Significant Accounting Policies (Policy)

9 Months Ended

Jun. 30, 2011

Significant Accounting Policies

Revenue Recognition and Accounts Receivable

The following table shows the relative size of the revenue recognized in each of the Company's reportable segments.


	Three months ended						Nine months ended
	June 30						June 30
	2011			2010			2011			2010

Core Segment
Rubber Blacks Business		62	%		60	%		61	%		60	%
Supermetals Business		6	%		7	%		6	%		6	%
Performance Segment		28	%		27	%		28	%		28	%
New Business Segment		3	%		3	%		3	%		3	%
Specialty Fluids Segment		1	%		3	%		2	%		3	%

Goodwill And Long-Lived Assets

Goodwill and Long-Lived Assets

Financial Instruments

Financial Instruments

Income Tax In Interim Periods

Income Tax in Interim Periods

Inventory Valuation

Inventory Valuation


	Three months ended				Nine months ended
	June 30				June 30
	2011		2010		2011		2010
	(Dollars in millions, except per share amounts)
Decrease in cost of sales	$	6	$	8	$	20	$	15
Increase in net income	$	4	$	5	$	13	$	9
Increase in net income per diluted common share	$	0.06	$	0.08	$	0.20	$	0.15

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Disclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction.

Percentages Of Total Net Sales And Other Operating Revenues

Significant Accounting Policies (Tables)

9 Months Ended

Jun. 30, 2011

Significant Accounting Policies


	Three months ended						Nine months ended
	June 30						June 30
	2011			2010			2011			2010

Core Segment
Rubber Blacks Business		62	%		60	%		61	%		60	%
Supermetals Business		6	%		7	%		6	%		6	%
Performance Segment		28	%		27	%		28	%		28	%
New Business Segment		3	%		3	%		3	%		3	%
Specialty Fluids Segment		1	%		3	%		2	%		3	%

Inventory Quantities Reduction


	Three months ended				Nine months ended
	June 30				June 30
	2011		2010		2011		2010
	(Dollars in millions, except per share amounts)
Decrease in cost of sales	$	6	$	8	$	20	$	15
Increase in net income	$	4	$	5	$	13	$	9
Increase in net income per diluted common share	$	0.06	$	0.08	$	0.20	$	0.15

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Goodwill And Other Intangible Assets

Goodwill And Other Intangible Assets (Tables)

9 Months Ended

Jun. 30, 2011

Schedule Of Goodwill Balances


	Rubber Blacks		Fumed Metal Oxides		Security Materials		Total
	(Dollars in millions)
Balance at September 30, 2010	$	27	$	11	$	1	$	39
Foreign currency translation adjustment and other		—		1		1		2

Balance at June 30, 2011	$	27	$	12	$	2	$	41

Tabular disclosure of goodwill by reportable segment and in total. Disclosure details may include, but are not limited to, the carrying amount of goodwill, goodwill acquired during the year, goodwill impairment losses recognized, goodwill written-off due to the sale of a business unit, goodwill not yet allocated, and any other changes to goodwill.

Net Periodic Defined Benefit Pension And Other Postretirement Benefit Costs

Employee Benefit Plans (Tables)

9 Months Ended

Jun. 30, 2011

Employee Benefit Plans


	Three Months Ended June 30
	2011						2010						2011					2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Service cost	$	1		$	2		$	1		$	1		$	—		$	—	$	1		$	—
Interest cost		2			2			2			2			1			—		1			—
Expected return on plan assets		(2	)		(3	)		(3	)		(3	)		—			—		—			—
Amortization of prior service credit		—			—			—			—			—			—		(1	)		—
Amortization of actuarial loss		—			—			—			1			—			—		—			—

Net periodic benefit cost	$	1		$	1		$	—		$	1		$	1		$	—	$	1		$	—


	Nine Months Ended June 30
	2011						2010						2011					2010
	Pension Benefits												Postretirement Benefits
	U.S.			Foreign			U.S.			Foreign			U.S.			Foreign		U.S.			Foreign
	(Dollars in millions)
Service cost	$	3		$	5		$	3		$	4		$	1		$	—	$	1		$	—
Interest cost		6			6			6			7			3			—		3			—
Expected return on plan assets		(6	)		(9	)		(7	)		(9	)		—			—		—			—
Amortization of prior service credit		—			—			—			—			(2	)		—		(3	)		—
Amortization of actuarial loss		—			2			—			2			—			—		—			—
Curtailment income		—			(1	)		—			—			—			—		—			—

Net periodic benefit cost	$	3		$	3		$	2		$	4		$	2		$	—	$	1		$	—

Commitments And Contingencies (Tables)

9 Months Ended

Jun. 30, 2011

Commitments And Contingencies

Schedule Of Components Of Purchase Commitments


	Payments Due by Fiscal Year
	Remainder of fiscal 2011		2012		2013		2014		2015		Thereafter		Total
	(Dollars in millions)
Core Segment:
Rubber Blacks Business	$	79	$	241	$	210	$	163	$	160	$	1,240	$	2,093
Supermetals Business		1		19		13		6		—		—		39
Performance Segment		4		17		29		30		30		302		412
New Business Segment		—		1		1		—		—		—		2

Total	$	84	$	278	$	253	$	199	$	190	$	1,542	$	2,546

Income Tax Uncertainties (Tables)

9 Months Ended

Jun. 30, 2011

Income Tax Uncertainties

Reconciliation Of Unrecognized Tax Benefits


	Nine months ended June 30
	2011			2010
	(Dollars in millions)
Balance at beginning of the period	$	75		$	81
Additions based on tax positions related to the current year		2			5
Additions based on tax positions of prior years		2			1
Reduction for tax positions of prior years		(6	)		(14	)

Balance at end of the period	$	73		$	73

Tabular disclosure of tax positions taken in the tax returns filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities (i.e., uncertain tax positions) and other types of income tax contingencies, including: (1) the policy on classification of interest and penalties; (2) a tabular reconciliation of the total amounts of unrecognized tax benefits at the beginning and end of the period; the total amount(s) of: (3) unrecognized tax benefits that, if recognized, would affect the effective tax rate, and (4) interest and penalties recognized in each of the income statement and balance sheet; (5) for positions for which it is reasonably possible that the total amounts unrecognized will significantly change within 12 months of the reporting date the: (i) nature of the uncertainty, (ii) nature of the event that could occur that would cause the change, and (iii) an estimate of the range of the reasonably possible change or a statement that an estimate of the range cannot be made; and (6) a description of tax years that remain subject to examination by major tax jurisdictions.

Components Of Basic And Diluted Earnings Per Common Share

Earnings Per Share (Tables)

9 Months Ended

Jun. 30, 2011

Earnings Per Share


	Three Months Ended June 30					Nine Months Ended June 30
	2011		2010			2011			2010
	(Dollars and shares in millions, except per share amounts)
Basic EPS:
Net income attributable to Cabot Corporation	$	60	$	47		$	186		$	119
Less: Dividends and dividend equivalents to participating securities		—		—			1			1
Less: Undistributed earnings allocated to participating securities⁽¹⁾		—		1			2			2

Earnings allocated to common shareholders (numerator)	$	60	$	46		$	183		$	116

Weighted average common shares outstanding		65.4		65.3			65.4			65.3
Less: Participating securities⁽¹⁾		0.7		1.4			0.8			1.6

Adjusted weighted average common shares (denominator)		64.7		63.9			64.6			63.7


Basic EPS	$	0.93	$	0.72		$	2.84		$	1.82


Diluted EPS:
Earnings allocated to common shareholders	$	60	$	46		$	183		$	116
Plus: Earnings allocated to participating securities		—		1			3			3
Less: Adjusted earnings allocated to participating securities⁽²⁾		—		(1	)		(3	)		(3	)

Earnings allocated to common shareholders (numerator)	$	60	$	46		$	183		$	116

Adjusted weighted average common shares outstanding		64.7		63.9			64.6			63.7
Effect of dilutive securities:
Common shares issuable⁽³⁾		0.9		0.6			0.8			0.5

Adjusted weighted average common shares (denominator)		65.6		64.5			65.4			64.2


Diluted EPS	$	0.92	$	0.72		$	2.81		$	1.81

⁽¹⁾	Participating securities consist of shares of unvested restricted stock, vested restricted stock awards held by employees in which Cabot has a security interest, and unvested time-based restricted stock units.

⁽²⁾	Undistributed earnings are adjusted for the assumed distribution of dividends to the dilutive securities, which are described in (3) below, and then reallocated to participating securities.

⁽³⁾

Calculation Of Undistributed Earnings


	Three Months Ended June 30				Nine Months Ended June 30
	2011		2010		2011		2010
	(Dollars in millions)
Calculation of undistributed earnings:
Net income attributable to Cabot Corporation	$	60	$	47	$	186	$	119
Less: Dividends declared on common stock		11		12		34		34
Less: Dividends declared on participating securities		—		—		1		1

Undistributed earnings	$	49	$	35	$	151	$	84

Allocation of undistributed earnings:
Undistributed earnings allocated to common shareholders	$	49	$	34	$	149	$	82
Undistributed earnings allocated to participating shareholders		—		1		2		2

Undistributed earnings	$	49	$	35	$	151	$	84

Restructuring (Tables)

3 Months Ended

9 Months Ended

Jun. 30, 2011

Restructuring

Recorded Restructuring Activities


	Three Months Ended June 30				Nine Months Ended June 30
	2011		2010		2011		2010
	(Dollars in millions)
Cost of sales	$	5	$	12	$	15	$	23
Selling and administrative expenses		—		2		1		15

Total	$	5	$	14	$	16	$	38

Restructuring Activities And Related Reserves


	Severance and Employee Benefits			Environmental Remediation			Asset Impairment and Accelerated Depreciation			Other			Total
	(Dollars in millions)
Reserve at March 31, 2011	$	14		$	2		$	—		$	1		$	17
Charges		2			1			1			1			5
Costs charged against assets/liabilities		—			—			(1	)		—			(1	)
Cash paid		(3	)		(2	)		—			(1	)		(6	)

Reserve at June 30, 2011	$	13		$	1		$	—		$	1		$	15


	Severance and Employee Benefits			Environmental Remediation			Asset Impairment and Accelerated Depreciation			Other			Total
	(Dollars in millions)
Reserve at September 30, 2010	$	18		$	1		$	—		$	—		$	19
Charges		6			2			4			4			16
Costs charged against assets / liabilities		—			—			(4	)		1			(3	)
Cash paid		(12	)		(2	)		—			(4	)		(18	)
Foreign currency translation adjustment		1			—			—			—			1

Reserve at June 30, 2011	$	13		$	1		$	—		$	1		$	15

Fair Value Measurements (Tables)

9 Months Ended

Jun. 30, 2011

Fair Value Measurements

Schedule Of Fair Value Of Derivatives, Net Of Legal Right To Offset Derivative Settlements


	June 30, 2011		September 30, 2010
	Level 2 Inputs		Level 2 Inputs
	(Dollars in millions)
Assets at fair value:
Guaranteed investment contract⁽¹⁾	$	15	$	14
Derivatives relating to:
Interest rates⁽²⁾		3		5
Foreign currency⁽²⁾		1		—

Total assets at fair value	$	19	$	19

Liabilities at fair value:
Derivatives relating to: Foreign currency⁽²⁾	$	50	$	42

Total liabilities at fair value	$	50	$	42

⁽¹⁾	Included in "Other assets" in the consolidated balance sheets.

⁽²⁾	Included in "Prepaid expenses and other current assets", "Other assets", "Accounts payable and accrued liabilities" or "Other liabilities" in the consolidated balance sheets.

Fair Value Of Financial Instruments (Tables)

9 Months Ended

Jun. 30, 2011

Fair Value Of Financial Instruments

Carrying Amounts And Fair Values Of Company's Financial Instruments


	June 30, 2011				September 30, 2010
	Carrying		Fair		Carrying		Fair
	Amount		Value		Amount		Value
	(Dollars in millions)
Assets:
Cash and cash equivalents	$	344	$	344	$	387	$	387
Accounts and notes receivable		697		697		576		576
Derivative instruments		1		1		2		2
Liabilities:
Notes payable to banks		61		61		29		29
Accounts payable and accrued liabilities		429		429		447		447
Long-term debt—fixed rate		582		631		604		661
Long-term debt—floating rate		18		18		16		16
Capital lease obligations		4		4		3		3
Derivative instruments		47		47		39		39

Financial Instruments (Tables)

9 Months Ended

Jun. 30, 2011

Schedule Of Derivative Instruments In Statement Of Financial Position, Fair Value


	Consolidated Balance Sheet Caption	June 30, 2011		September 30, 2010
		(Dollars in millions)
Fair Value of Derivative Instruments
Asset Derivatives
Derivatives designated as hedges
Interest rate⁽¹⁾	Prepaid expenses and other current assets, Other assets, and Other liabilities	$	3	$	5

Total derivatives designated as hedges		$	3	$	5

Derivatives not designated as hedges
Foreign currency	Prepaid expenses and other current assets	$	1	$	—
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	2	$	2

Total Asset Derivatives		$	5	$	7

Liability Derivatives
Derivatives not designated as hedges
Foreign currency⁽¹ ⁾	Accounts payable and accrued liabilities, and Other liabilities	$	50	$	42
Commodity contracts⁽²⁾	Prepaid expenses and other current assets, and Other assets		1		2

Total derivatives not designated as hedges		$	51	$	44

Total Liability Derivatives		$	51	$	44

⁽¹⁾	Contracts of $3 million and $4 million presented on a gross basis in this table at June 30, 2011 and September 30, 2010, respectively, have the legal right to offset against other types of contracts with a common counterparty and, therefore, are presented on a net basis in noncurrent "Other liabilities" in the consolidated balance sheet.
⁽²⁾	Contracts in an asset and liability position presented on a gross basis in this table have the legal right of offset and, therefore, are presented on a net basis in "Prepaid expenses and other current assets" and noncurrent "Other assets" in the consolidated balance sheet.

Interest Rate Risk Management [Member]

Schedule Of Derivatives Held To Manage Risk


		Notional Amount
Description	Borrowing	June 30 , 2011	September 30, 2010	Hedge Designation
Interest Rate Swap—Fixed to Variable	Eurobond (20% of $175 million)	USD 35 million	USD 35 million	Fair Value
Interest Rate Swap—Fixed to Variable⁽¹⁾	Medium Term Notes	—	USD 15 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 8 million	USD 8 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value
Interest Rate Swap—Fixed to Variable	Medium Term Notes	USD 5 million	USD 5 million	Fair Value

⁽¹⁾	Cabot's interest rate swap derivative instrument and the hedged debt borrowing matured during the second quarter of fiscal 2011.

Foreign Exchange Contract [Member]

Schedule Of Derivatives Held To Manage Risk


		Notional Amount		Hedge Designation
Description	Borrowing	June 30, 2011	September 30, 2010	Hedge Designation
Cross Currency Swap	Eurobond (80% of $175 million)	USD 140 million swapped to EUR 124 million	USD 140 million swapped to EUR 124 million		No designation

Cross Currency Swap	Eurobond (20% of $175 million)	USD 35 million swapped to EUR 31 million	USD 35 million swapped to EUR 31 million		No designation

Forward Foreign Currency Contracts ⁽¹⁾	N/A	USD 21 million	USD 23 million		No designation

Forward Foreign Currency Contracts ⁽²⁾	N/A	JPY 1,220 million	—		Cash Flow

⁽¹⁾	Cabot's forward foreign exchange contracts are denominated primarily in the Argentine peso, Australian dollar, Brazilian real, British pound sterling, Canadian dollar, Euro, and Japanese yen.

⁽²⁾	Cabot's forward foreign exchange contracts designated as cash flow hedges were entered into during the third quarter and first nine months of fiscal 2011.

Commodity Risk Management [Member]

Schedule Of Derivatives Held To Manage Risk

Net Buyer /
Net Seller

Notional Amount

Hedge
Designation

Description

June 30, 2011

September 30, 2010

CERs

Buyer

EUR 1 million

EUR 2 million

No designation

EUAs

Seller

EUR 1 million

EUR 2 million

No designation

The entire disclosure for the entity's entire derivative instruments and hedging activities. Describes an entity's risk management strategies, derivatives in hedging activities and non-hedging derivative instruments, the assets, obligations, liabilities, revenues and expenses arising therefrom, and the amounts of and methodologies and assumptions used in determining the amounts of such items.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 45
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 133
-Paragraph 44
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-SubTopic 10
-Section 50
-Paragraph 4J
-URI http://asc.fasb.org/extlink&oid=6935481&loc=SL5708773-113959

Reference 22: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6441202&loc=d3e80720-113993

Schedule Of Performance Of Segments And Allocate Resources

Financial Information By Segment (Tables)

9 Months Ended

Jun. 30, 2011

Financial Information By Segment


	Core Segment
	Rubber Blacks Business		Supermetals Business		Performance Segment		New Business Segment			Specialty Fluids Segment		Segment Total		Unallocated and Other			Consolidated Total
	(Dollars in millions)
Three months ended June 30, 2011
Net sales and other operating revenues⁽¹⁾	$	531	$	47	$	240	$	30		$	12	$	860	$	23		$	883
Income (loss) before taxes⁽²⁾	$	50	$	19	$	42	$	1		$	3	$	115	$	(32	)	$	83
Three months ended June 30, 2010
Net sales and other operating revenues⁽¹⁾	$	437	$	47	$	200	$	25		$	22	$	731	$	22		$	753
Income (loss) before taxes⁽²⁾	$	41	$	14	$	35	$	—		$	11	$	101	$	(31	)	$	70
Nine months ended June 30, 2011
Net sales and other operating revenues⁽¹⁾	$	1,436	$	158	$	652	$	77		$	42	$	2,365	$	62		$	2,427
Income (loss) before taxes⁽²⁾	$	138	$	61	$	109	$	(1	)	$	10	$	317	$	(92	)	$	225
Nine months ended June 30, 2010
Net sales and other operating revenues⁽¹⁾	$	1,247	$	128	$	587	$	64		$	52	$	2,078	$	66		$	2,144
Income (loss) before taxes⁽²⁾	$	122	$	23	$	101	$	(2	)	$	21	$	265	$	(108	)	$	157

⁽¹⁾	Unallocated and Other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.

⁽²⁾


	Three Months Ended June 30						Nine Months Ended June 30
	2011			2010			2011			2010
	(Dollars in millions)
Interest expense	$	(9	)	$	(10	)	$	(29	)	$	(30	)
Certain items^(a)		(5	)		(15	)		(16	)		(41	)
Equity in net income of affiliated companies^(b)		(2	)		(1	)		(6	)		(5	)
Unallocated corporate costs^(c)		(12	)		(9	)		(35	)		(30	)
Foreign currency transactions and other (losses) income, net^(d)		(4	)		4			(6	)		(2	)

Total	$	(32	)	$	(31	)	$	(92	)	$	(108	)

^(a)

^(b)	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and Other to reconcile to segment EBIT.

^(c)	Unallocated corporate costs are not controlled by the segments and primarily benefit corporate interests.

^(d)

Schedule Of Income (Loss) Before Taxes For Unallocated And Other


	Three Months Ended June 30						Nine Months Ended June 30
	2011			2010			2011			2010
	(Dollars in millions)
Interest expense	$	(9	)	$	(10	)	$	(29	)	$	(30	)
Certain items^(a)		(5	)		(15	)		(16	)		(41	)
Equity in net income of affiliated companies^(b)		(2	)		(1	)		(6	)		(5	)
Unallocated corporate costs^(c)		(12	)		(9	)		(35	)		(30	)
Foreign currency transactions and other (losses) income, net^(d)		(4	)		4			(6	)		(2	)

Total	$	(32	)	$	(31	)	$	(92	)	$	(108	)

^(a)

^(b)	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and Other to reconcile to segment EBIT.

^(c)	Unallocated corporate costs are not controlled by the segments and primarily benefit corporate interests.

^(d)

Schedule Of Segment Comprised Of Performance Products And Fumed Metal Oxides Businesses


	Three Months Ended				Nine Months Ended
	June 30				June 30
	2011		2010		2011		2010
	(Dollars in millions)
Performance Products	$	173	$	137	$	464	$	401
Fumed Metal Oxides		67		63		188		186

Total Performance Segment Sales	$	240	$	200	$	652	$	587

Schedule Of Segment Comprised Of Inkjet Colorants Aerogel Businesses And Superior MicroPowders


	Three Months Ended				Nine Months Ended
	June 30				June 30
	2011		2010		2011		2010
	(Dollars in millions)
Inkjet colorants	$	20	$	15	$	50	$	43
Aerogel		8		8		19		16
Superior MicroPowders		2		2		8		5

Total New Business Segment Sales	$	30	$	25	$	77	$	64

Basis Of Presentation (Details) $ in Millions	9 Months Ended
Basis Of Presentation (Details) $ in Millions	Jun. 30, 2011 USD ($)
Basis Of Presentation
Discontinued operations settlement benefit	$ 1

Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Sep. 30, 2010
Net tax benefits for discrete item			$ 30
Chance of utilizing the associated benefit for valuation allowances, maximum			50.00%
Value of inventories under FIFO method	$ 112		$ 112		$ 98
Inventory write-downs	$ 0	$ 0	0	$ 0
Repatriation Of High Tax Dividends [Member]
Net tax benefits for discrete item			23
Renewal Of Credit, Tax Credit, Tax Settlements And Releases [Member]
Net tax benefits for discrete item			$ 7

Charge to cost of goods sold that represents the reduction of the carrying amount of inventory, generally attributable to obsolescence or market conditions.

Significant Accounting Policies (Percentages Of Total Net Sales And Other Operating Revenues) (Details)	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Rubber Blacks Business [Member]
Revenue, by segment	62.00%	60.00%	61.00%	60.00%
Supermetals Business [Member]
Revenue, by segment	6.00%	7.00%	6.00%	6.00%
Performance Segment [Member]
Revenue, by segment	28.00%	27.00%	28.00%	28.00%
New Business Segment [Member]
Revenue, by segment	3.00%	3.00%	3.00%	3.00%
Specialty Fluids Segment [Member]
Revenue, by segment	1.00%	3.00%	2.00%	3.00%

Significant Accounting Policies (Inventory Quantities Reduction) (Details) - Supermetals Business [Member] $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011 USD ($) $ / shares	Jun. 30, 2010 USD ($) $ / shares	Jun. 30, 2011 USD ($) $ / shares	Jun. 30, 2010 USD ($) $ / shares
Decrease in cost of sales	$ 6	$ 8	$ 20	$ 15
Increase in net income	$ 4	$ 5	$ 13	$ 9
Increase in net income per diluted common share \| $ / shares	0.06	0.08	0.20	0.15

Goodwill And Other Intangible Assets (Narrative) (Details) $ in Millions	6 Months Ended	9 Months Ended
	Mar. 31, 2011 USD ($)	Jun. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)
Goodwill annual impairment	$ 0
Indefinite-lived intangible assets		$ 0
Finite-lived intangible assets		$ 4	$ 4
Useful life of intangible assets, minimum (years)		6
Useful life of intangible assets, maximum (years)		14
Useful life of intangible assets, average (years)		10
Maximum [Member]
Amortization of intangible assets, year one		$ 1
Amortization of intangible assets, year two		1
Amortization of intangible assets, year three		1
Amortization of intangible assets, year four		1
Amortization of intangible assets, year five		$ 1

Goodwill And Other Intangible Assets (Schedule of Goodwill Balances) (Details) $ in Millions	9 Months Ended
	Jun. 30, 2011 USD ($)
Balance at September 30, 2010	$ 39
Foreign currency translation adjustment and other	2
Balance at June 30, 2011	41
Rubber Blacks Business [Member]
Balance at September 30, 2010	27
Foreign currency translation adjustment and other
Balance at June 30, 2011	27
Fumed Metal Oxides [Member]
Balance at September 30, 2010	11
Foreign currency translation adjustment and other	1
Balance at June 30, 2011	12
Security Materials Business [Member]
Balance at September 30, 2010	1
Foreign currency translation adjustment and other	1
Balance at June 30, 2011	$ 2

Carrying amount as of the balance sheet date, which is the cumulative amount paid and (if applicable) the fair value of any noncontrolling interest in the acquiree, adjusted for any amortization recognized prior to the adoption of any changes in generally accepted accounting principles (as applicable) and for any impairment charges, in excess of the fair value of net assets acquired in one or more business combination transactions.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph e
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 43
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 68
-Subparagraph l
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13816-109267

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 72
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Paragraph 45
-Subparagraph e
-Clause 1
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 34
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

The increase (decrease) in the recorded value of goodwill for foreign currency translation adjustments and purchase accounting adjustments needed to revise the carrying amount of goodwill to fair value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Subparagraph e
-Paragraph 45
-Clause 6
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=6905597&loc=d3e13816-109267

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 141R
-Paragraph 72
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Subparagraph e
-Paragraph 45
-Clause 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 142
-Subparagraph e
-Paragraph 45
-Clause 7
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Employee Benefit Plans (Narrative) (Details) $ in Millions	9 Months Ended
Employee Benefit Plans (Narrative) (Details) $ in Millions	Jun. 30, 2011 USD ($)
Employee Benefit Plans
Net gain associated with curtailments	$ 1

Employee Benefit Plans (Net Periodic Defined Benefit Pension And Other Postretirement Benefit Costs) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
U.S. Pension Benefits [Member]
Service cost	$ 1	$ 1	$ 3	$ 3
Interest cost	2	2	6	6
Expected return on plan assets	(2)	(3)	(6)	(7)
Amortization of prior service credit
Amortization of actuarial loss
Curtailment income
Net periodic benefit cost	1		3	2
Foreign Pension Benefits [Member]
Service cost	2	1	5	4
Interest cost	2	2	6	7
Expected return on plan assets	(3)	(3)	(9)	(9)
Amortization of prior service credit
Amortization of actuarial loss		1	2	2
Curtailment income			(1)
Net periodic benefit cost	1	1	3	4
U.S. Postretirement Benefits [Member]
Service cost		1	1	1
Interest cost	1	1	3	3
Expected return on plan assets
Amortization of prior service credit		(1)	(2)	(3)
Amortization of actuarial loss
Curtailment income
Net periodic benefit cost	1	1	2	1
Foreign Postretirement Benefits [Member]
Service cost
Interest cost
Expected return on plan assets
Amortization of prior service credit
Amortization of actuarial loss
Curtailment income
Net periodic benefit cost

Commitments And Contingencies (Narrative) (Details) $ in Millions	9 Months Ended		12 Months Ended
	Jun. 30, 2011 USD ($)	Jun. 30, 2010 USD ($)	Sep. 30, 2010 USD ($)
Legal judgment benefit	$ 9
Environmental Matters [Member]
Environmental reserve on discounted and undiscounted basis	6		$ 7
Cash payments for environmental reserves	$ 2	$ 1
Respirator Liabilities [Member]
Number of claimants	43,000		45,000
Respirator reserve on discounted basis	$ 12		$ 15
Respirator reserve on undiscounted basis	17		$ 20
Cash payments for respirator reserves	$ 3	$ 1

Commitments And Contingencies (Schedule Of Components Of Purchase Commitments) (Details) $ in Millions	Jun. 30, 2011 USD ($)
Payments Due by Fiscal Year 2011	$ 84
Payments Due by Fiscal Year 2012	278
Payments Due by Fiscal Year 2013	253
Payments Due by Fiscal Year 2014	199
Payments Due by Fiscal Year 2015	190
Payments Due Thereafter	1,542
Payments Due, Total	2,546
Rubber Blacks Business [Member]
Payments Due by Fiscal Year 2011	79
Payments Due by Fiscal Year 2012	241
Payments Due by Fiscal Year 2013	210
Payments Due by Fiscal Year 2014	163
Payments Due by Fiscal Year 2015	160
Payments Due Thereafter	1,240
Payments Due, Total	2,093
Supermetals Business [Member]
Payments Due by Fiscal Year 2011	1
Payments Due by Fiscal Year 2012	19
Payments Due by Fiscal Year 2013	13
Payments Due by Fiscal Year 2014	6
Payments Due by Fiscal Year 2015
Payments Due Thereafter
Payments Due, Total	39
Performance Segment [Member]
Payments Due by Fiscal Year 2011	4
Payments Due by Fiscal Year 2012	17
Payments Due by Fiscal Year 2013	29
Payments Due by Fiscal Year 2014	30
Payments Due by Fiscal Year 2015	30
Payments Due Thereafter	302
Payments Due, Total	412
New Business Segment [Member]
Payments Due by Fiscal Year 2011
Payments Due by Fiscal Year 2012	1
Payments Due by Fiscal Year 2013	1
Payments Due by Fiscal Year 2014
Payments Due by Fiscal Year 2015
Payments Due Thereafter
Payments Due, Total	$ 2

Income Tax Uncertainties (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2010	Sep. 30, 2009
Income Tax Uncertainties
Unrecognized tax benefits	$ 73	$ 75	$ 73	$ 81
Unrecognized tax benefits, recorded	47
Unrecognized tax benefits, not recorded	26
Accruals for penalties	5
Accruals for interest	15
Favorable impact if unrecognized tax benefits were recognized	36
Reduction of unrecognized tax benefits	$ (6)

Income Tax Uncertainties (Reconciliation Of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Income Tax Uncertainties
Balance at beginning of the period	$ 75	$ 81
Additions based on tax positions related to the current year	2	5
Additions based on tax positions of prior years	2	1
Reduction for tax positions of prior years	(6)	(14)
Balance at end of the period	$ 73	$ 73

Earnings Per Share (Components Of Basic And Diluted Earnings Per Common Share) (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions

3 Months Ended

9 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Jun. 30, 2011

Jun. 30, 2010

Basic EPS:

Less: Dividends and dividend equivalents to participating securities

$ 60

$ 47

$ 186

$ 119

Less: Undistributed earnings allocated to participating securities

^[1]

Earnings allocated to common shareholders (numerator)

$ 60

$ 46

$ 183

$ 116

Weighted average common shares outstanding

65.4

65.3

65.4

65.3

Less: Participating securities

^[1]

0.7

1.4

0.8

1.6

Adjusted weighted average common shares (denominator)

64.7

63.9

64.6

63.7

Basic EPS

$ 0.93

$ 0.72

$ 2.84

$ 1.82

Diluted EPS:

Earnings allocated to common shareholders

$ 60

$ 46

$ 183

$ 116

Plus: Earnings allocated to participating securities

Less: Adjusted earnings allocated to participating securities

^[2]

(1)

(3)

Earnings allocated to common shareholders (numerator)

$ 60

$ 46

$ 183

$ 116

Adjusted weighted average common shares outstanding

64.7

63.9

64.6

63.7

Common shares issuable

^[3]

0.9

0.6

0.8

0.5

Adjusted weighted average shares (denominator)

65.6

64.5

65.4

64.2

Diluted EPS

$ 0.92

$ 0.72

$ 2.81

$ 1.81

[1]	Participating securities consist of shares of unvested restricted stock, vested restricted stock awards held by employees in which Cabot has a security interest, and unvested time-based restricted stock units.
[2]	Undistributed earnings are adjusted for the assumed distribution of dividends to the dilutive securities, which are described in (3) below, and then reallocated to participating securities.
[3]	Represents incremental shares of common stock from the (i) assumed exercise of stock options issued under Cabot's equity incentive plans; (ii) assumed issuance of shares to employees pursuant to the Company's Supplemental Retirement Savings Plan; and (iii) assumed issuance of shares under outstanding performance-based stock unit awards issued under Cabot's equity incentive plans. For the three and nine months ended June 30, 2011, 121,000 and 271,000 incremental shares of common stock, respectively, were not included in the calculation of diluted earnings per share because the inclusion of these shares would have been anti-dilutive. For both the three and nine months ended June 30, 2010, 206,000 incremental shares of common stock were not included in the calculation of diluted earnings per share because the options' exercise prices were greater than the average market price of Cabot common stock for the relevant period.

Earnings Per Share (Calculation Of Undistributed Earnings) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Earnings Per Share
Net income attributable to Cabot Corporation	$ 60	$ 47	$ 186	$ 119
Less: Dividends declared on common stock	11	12	34	34
Less: Dividends declared on participating securities			1	1
Undistributed earnings allocated to common shareholders	49	34	149	82
Undistributed earnings allocated to participating shareholders		1	2	2
Undistributed earnings	$ 49	$ 35	$ 151	$ 84
Shares excluded from calculation of EPS	121,000	206,000	271,000	206,000

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 13, 14
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 171
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 128
-Paragraph 40
-Subparagraph c
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 07-4
-Paragraph 4
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Publisher FASB
-Name Emerging Issues Task Force (EITF)
-Number 87-21
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph a
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 130
-Paragraph 10, 15
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 28, 29, 30
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 5
-Section 03
-Paragraph 19

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 20
-Article 9

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Net Income
-URI http://asc.fasb.org/extlink&oid=6518256

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Other Comprehensive Income
-URI http://asc.fasb.org/extlink&oid=6519514

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 260
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.18)
-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.19)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 13: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6920043&loc=d3e565-108580

Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.22)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph 38
-Subparagraph d
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 16: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Research Bulletin (ARB)
-Number 51
-Paragraph A7
-Appendix A

Guaranteed investment contract

Restructuring (Narrative) (Details) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
Restructuring (Narrative) (Details) $ in Millions	Feb. 28, 2011	Jun. 30, 2011 USD ($)	Jun. 30, 2011 USD ($)	Sep. 30, 2010 USD ($)	Sep. 30, 2009	Mar. 31, 2011 USD ($)
Restructuring costs in accrued expenses		$ 15	$ 15	$ 19		$ 17
Closure Of Grigno [Member]
Affected employees	37
Restructuring accelerated depreciation and asset impairments			3
Restructuring charges			6
Severance costs		3	4
Expected severance related restructuring charges payment		4	4
Cash payments			1
Expected cash outlays remainder fiscal year		1	1
Expected cash outlays beyond fiscal year		2	2
Restructuring costs in accrued expenses		2	2
Closure Of Thane [Member]
Affected employees				120
Pre-tax charge to earnings			20
Restructuring accelerated depreciation and asset impairments			10
Restructuring charges			19
Severance costs			6
Expected cash outlays		8	8
Cash payments			7
Expected cash outlays remainder fiscal year		1	1
Restructuring costs in accrued expenses		1	1
Closure Of Thane [Member] \| Demolition And Site Clearing Costs [Member]
Restructuring charges			1
Closure Of Thane [Member] \| Other Post Closing Costs [Member]
Restructuring charges			$ 2
2009 Global Restructuring [Member]
Affected employees			400
Number of facilities closed					3
Pre-tax charge to earnings			$ 124
Restructuring accelerated depreciation and asset impairments			48
Restructuring charges			123
Severance costs			55
Expected cash outlays		69	69
Cash payments			65
Expected cash outlays remainder fiscal year		4	4
Restructuring costs in accrued expenses		$ 8	8
2009 Global Restructuring [Member] \| Demolition And Site Clearing Costs [Member]
Restructuring charges			5
2009 Global Restructuring [Member] \| Other Post Closing Costs [Member]
Restructuring charges			$ 15

Restructuring (Recorded Restructuring Activities) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Restructuring reserve, period expense	$ 5	$ 14	$ 16	$ 38
Cost Of Sales [Member]
Restructuring reserve, period expense	5	12	15	23
Selling And Administrative Expenses [Member]
Restructuring reserve, period expense		$ 2	$ 1	$ 15

Restructuring (Restructuring Activities And Related Reserves) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Reserve at beginning of period	$ 17		$ 19
Charges	5	$ 14	16	$ 38
Costs charged against assets / liabilities	(1)		(3)
Cash paid	(6)		(18)
Foreign currency translation adjustment			1
Reserve at end of period	15		15
Severance And Employee Benefits [Member]
Reserve at beginning of period	14		18
Charges	2		6
Costs charged against assets / liabilities	0
Cash paid	(3)		(12)
Foreign currency translation adjustment			1
Reserve at end of period	13		13
Environmental Remediation [Member]
Reserve at beginning of period	2		1
Charges	1		2
Costs charged against assets / liabilities	0
Cash paid	(2)		(2)
Foreign currency translation adjustment
Reserve at end of period	1		1
Asset Impairment And Accelerated Depreciation [Member]
Reserve at beginning of period
Charges	1		4
Costs charged against assets / liabilities	(1)		(4)
Cash paid
Foreign currency translation adjustment
Reserve at end of period
Corporate And Other [Member]
Reserve at beginning of period	1
Charges	1		4
Costs charged against assets / liabilities	0		1
Cash paid	(1)		(4)
Foreign currency translation adjustment
Reserve at end of period	$ 1		$ 1

Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Recorded impairment charge			$ 2
Fair Value, Assets And Liabilities Measured On Nonrecurring Basis, Losses [Member]
Fair value of assets, land	$ 0	$ 0	$ 0	$ 6

Fair Value Measurements (Schedule Of Fair Value Of Derivatives, Net Of Legal Right To Offset Derivative Settlements) - Fair Value, Inputs, Level 2 [Member] - USD ($)
$ in Millions

Jun. 30, 2011

Sep. 30, 2010

^[1]

$ 15

$ 14

Derivatives assets relating to interest rates

^[2]

Derivatives assets relating to foreign currency

^[2]

Total assets at fair value

Derivatives liabilities relating to foreign currency

^[2]

Total liabilities at fair value

$ 50

$ 42

[1]	Included in "Other assets" in the consolidated balance sheets.
[2]	Included in "Prepaid expenses and other current assets", "Other assets", "Accounts payable and accrued liabilities" or "Other liabilities" in the consolidated balance sheets.

Fair Value Of Financial Instruments (Carrying Amounts And Fair Values Of Company's Financial Instruments) (Details) - USD ($) $ in Millions	Jun. 30, 2011	Sep. 30, 2010	Jun. 30, 2010	Sep. 30, 2009
Cash and cash equivalents, Carrying Amount	$ 344	$ 387	$ 295	$ 304
Cash and cash equivalents, Fair Value	344	387
Accounts and notes receivable, Carrying Amount	697	576
Accounts and notes receivable, Fair Value	697	576
Derivative instruments, Carrying Amount	1	2
Derivative instruments, Fair Value	1	2
Notes payable to banks, Carrying Amount	61	29
Notes payable to banks, Fair Value	61	29
Accounts payable and accrued liabilities, Carrying Amount	429	447
Accounts payable and accrued liabilities, Fair Value	429	447
Capital lease obligations, Carrying Amount	4	3
Capital lease obligations, Fair Value	4	3
Derivative instruments, Carrying Amount	47	39
Derivative instruments, Fair Value	47	39
Fixed Rate [Member]
Long-term debt, Carrying Amount	582	604
Long-term debt, Fair Value	631	661
Floating Rate [Member]
Long-term debt, Carrying Amount	18	16
Long-term debt, Fair Value	$ 18	$ 16

Financial Instruments (Narrative) (Details) $ in Millions, in Millions, ¥ in Billions	3 Months Ended				9 Months Ended		12 Months Ended
	Jun. 30, 2011 USD ($)	Dec. 31, 2010 VEF ( )	Jun. 30, 2010 USD ($)	Dec. 31, 2009 USD ($)	Jun. 30, 2011 USD ($)	Jun. 30, 2010 USD ($)	Sep. 30, 2010 USD ($)	Dec. 31, 2009 JPY (¥)	Dec. 31, 2009 USD ($)
Maximum remaining maturity of foreign currency derivatives, days	30				30
Number of open derivatives designated as net investment hedges					no
Notional amount of swap								¥ 2.5	$ 20
Cash settlement payment				$ 7
Gains or losses reclassified from accumulated other comprehensive income to earnings	$ 0		$ 0		$ 0	$ 0
Foreign currency exchange rate, remeasurement income (loss)	3	(1)	(17)		9	(32)
Bond held by one of Cabot's European subsidiaries	175		175		175	175
Loss related to investment hedge					27		$ 27
Forward Foreign Currency Contract [Member]
Gain (loss) on foreign currency derivative instruments not designated as hedging instruments	1		3		1	6
Currency Swap [Member]
Gain (loss) on foreign currency derivative instruments not designated as hedging instruments	$ 3		$ 19		$ 6	$ 34

Financial Instruments (Interest Rate Risk Management) (Details) - USD ($)

Jun. 30, 2011

Sep. 30, 2010

Percentage of debt hedged by interest rate derivatives

20.00%

Notional amount of interest rate fair value hedge derivatives

$ 175,000,000

35,000,000

$ 35,000,000

Medium Term Notes [Member]

Notional amount of interest rate fair value hedge derivatives

^[1]

15,000,000

Medium Term Notes With Notional Amount Of 8 Million [Member]

Notional amount of interest rate fair value hedge derivatives

8,000,000

Interest Rate Swap One [Member] | Medium Term Notes With Notional Amount Of 5 Million [Member]

Notional amount of interest rate fair value hedge derivatives

5,000,000

Interest Rate Swap Two [Member] | Medium Term Notes With Notional Amount Of 5 Million [Member]

Notional amount of interest rate fair value hedge derivatives

5,000,000

Interest Rate Swap Three [Member] | Medium Term Notes With Notional Amount Of 5 Million [Member]

Notional amount of interest rate fair value hedge derivatives

$ 5,000,000

[1]	Cabot's interest rate swap derivative instrument and the hedged debt borrowing matured during the second quarter of fiscal 2011.

Financial Instruments (Foreign Currency Risk Management) (Details)
€ in Millions, ¥ in Millions

Jun. 30, 2011

EUR (€)

Jun. 30, 2011

JPY (¥)

Jun. 30, 2011

USD ($)

Sep. 30, 2010

EUR (€)

Sep. 30, 2010

JPY (¥)

Sep. 30, 2010

USD ($)

$ 175,000,000

Eurobond 20% [Member]

Percentage of debt hedged by cross currency swaps

$ 175,000,000

20.00%

Notional amount of foreign currency derivative instruments not designated as hedging instruments

€ 31

$ 35,000,000

€ 31

$ 35,000,000

Eurobond 80% [Member]

Percentage of debt hedged by cross currency swaps

$ 175,000,000

80.00%

Notional amount of foreign currency derivative instruments not designated as hedging instruments

€ 124

$ 140,000,000

€ 124

140,000,000

Forward Foreign Currency Contracts [Member]

Notional amount of foreign currency derivative instruments not designated as hedging instruments

^[1]

$ 21,000,000

$ 23,000,000

Notional Amount of Foreign Currency Cash Flow Hedge Derivatives | ¥

^[2]

¥ 1,220

[1]	Cabot's forward foreign exchange contracts are denominated primarily in the Argentine peso, Australian dollar, Brazilian real, British pound sterling, Canadian dollar, Euro, and Japanese yen.
[2]	Cabot's forward foreign exchange contracts designated as cash flow hedges were entered into during the third quarter and first nine months of fiscal 2011.

Financial Instruments (Commodity Risk Management) (Details) - EUR (€) € in Millions	Jun. 30, 2011	Sep. 30, 2010
EUAs [Member]
Notional amount of commodity risk derivatives	€ 1	€ 2
CERs [Member]
Notional amount of commodity risk derivatives	€ 1	€ 2

Financial Instruments (Schedule Of Derivative Instruments In Statement Of Financial Position, Fair Value) (Details) - USD ($)
$ in Millions

Jun. 30, 2011

Sep. 30, 2010

$ 5

$ 7

Other Liabilities [Member] | Interest Rate Risk Management [Member]

Interest rate contracts with right of offset

Designated As Hedging Instrument [Member] | Interest Rate Risk Management [Member]

Designated As Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets, Other assets, And Other liabilities [Member] | Interest Rate Risk Management [Member]

^[1]

Not Designated As Hedging Instrument [Member]

^[1]

Not Designated As Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets [Member] | Foreign Exchange Contract [Member]

Not Designated As Hedging Instrument [Member] | Prepaid Expenses And Other Current Assets And Other Assets [Member] | Commodity Risk Management [Member]

^[2]

^[2]

^[2]

Not Designated As Hedging Instrument [Member] | Accounts Payable And Accrued Liabilities, And Other Liabilities [Member] | Foreign Exchange Contract [Member]

^[2]

^[1]

^[1]

$ 50

$ 42

[1]	Contracts of $3 million and $4 million presented on a gross basis in this table at June 30, 2011 and September 30, 2010, respectively, have the legal right to offset against other types of contracts with a common counterparty and, therefore, are presented on a net basis in noncurrent "Other liabilities" in the consolidated balance sheet.
[2]	Contracts in an asset and liability position presented on a gross basis in this table have the legal right of offset and, therefore, are presented on a net basis in "Prepaid expenses and other current assets" and noncurrent "Other assets" in the consolidated balance sheet.

Venezuela (Narrative) (Details) $ in Millions, in Millions	3 Months Ended							9 Months Ended
Venezuela (Narrative) (Details) $ in Millions, in Millions	Jun. 30, 2011 VEF ( ) / $	Jun. 30, 2011 USD ($)	Mar. 31, 2011 VEF ( ) / $	Dec. 31, 2010 VEF ( ) / $	Jun. 30, 2010 USD ($)	Mar. 31, 2010 USD ($) / $	Sep. 30, 2009 USD ($) / $	Jun. 30, 2011 USD ($)	Jun. 30, 2010 VEF ( ) / $	Jun. 30, 2010 USD ($)	Jun. 30, 2011 USD ($) / $	Sep. 30, 2010 USD ($)	May 31, 2010 / $	Jan. 31, 2010 / $
Equity method investment, ownership percentage	49.00%										49.00%
Operating affiliate investment \| $											$ 25
Due from affiliates, dividends receivable	21		21	20							$ 5
Venezuelan Bolivar exchange rate to one USD				6.57
Foreign currency exchange rate, remeasurement income (loss)		$ 3		(1)	$ (17)			$ 9		$ (32)
Cash from dividends paid \|			1	15
Assets held by affiliates, valued	5											$ 3
Participated in bond offering, value \|				4
Dividend Income [Member]
Due from affiliates, dividends receivable \|									8
Cash from dividends paid \|									5
Parallel Rate [Member]
Venezuelan Bolivar exchange rate to one USD						7.0	5.55
Foreign currency exchange rate, remeasurement income (loss) \| $							$ 6
Official Rate [Member]
Venezuelan Bolivar exchange rate to one USD				4.30										2.15
Essential Rate [Member]
Venezuelan Bolivar exchange rate to one USD														2.60
Non-Essentials Rate [Member]
Venezuelan Bolivar exchange rate to one USD						4.30			4.30					4.30
Foreign currency exchange rate, remeasurement income (loss) \| $		$ 1				$ 1
SITME [Member]
Venezuelan Bolivar exchange rate to one USD													5.3
Prior To Currency Exchange Rate Adjustment [Member] \| Essential Rate [Member]
Venezuelan Bolivar exchange rate to one USD			2.60
After Currency Exchange Rate Adjustment [Member] \| Essential Rate [Member]
Venezuelan Bolivar exchange rate to one USD			4.30
Unremitted Earnings [Member]
Foreign currency exchange rate, remeasurement income (loss) \| $						$ 2
Subsequent Event Information [Member]
Venezuelan Bolivar exchange rate to one USD	4.30										4.30
Cash from dividends paid \|	4

Financial Information By Segment (Schedule Of Performance Of Segments And Allocated Resources) (Details) - USD ($)
$ in Millions

3 Months Ended

9 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Jun. 30, 2011

Jun. 30, 2010

Net sales and other operating revenues, Consolidated Total

$ 96

$ 77

$ 251

$ 188

^[1]

883

753

2,427

2,144

Income from continuing operations before income taxes and equity in net income of affiliated companies

^[2]

225

157

Rubber Blacks Business [Member]

^[1]

531

437

1,436

1,247

Supermetals Business [Member]

^[2]

138

122

^[1]

158

128

Performance Segment [Member]

^[2]

^[1]

240

200

652

587

New Business Segment [Member]

^[2]

109

101

^[1]

Specialty Fluids Segment [Member]

^[2]

(1)

(2)

^[1]

^[2]

Segment Total [Member]

^[1]

860

731

2,365

2,078

Unallocated And Other [Member]

^[2]

115

101

317

265

^[1]

Equity in net income of affiliated companies

^[2]

$ (32)

$ (31)

$ (92)

$ (108)

[1]

Unallocated and Other reflects royalties paid by equity affiliates, external shipping and handling fees, and the impact of the corporate adjustment for unearned revenue.

[2]

Financial Information By Segment (Schedule Of Income (Loss) Before Taxes For Unallocated And Other) (Details) - USD ($)
$ in Millions

3 Months Ended

9 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Jun. 30, 2011

Jun. 30, 2010

Interest expense

$ (9)

$ (10)

$ (29)

$ (30)

^[1]

(2)

(1)

(6)

(5)

Unallocated corporate costs

^[2]

(12)

(9)

(35)

(30)

Foreign currency transactions and other (losses) income, net

^[3]

(4)

(6)

(2)

Total

(32)

(31)

(92)

(108)

Recovered from investment previously impaired

Benefit from a legal judgment

Certain Items [Member]

Certain items

^[4]

(5)

(15)

(16)

(41)

Impairment of long-lived assets to be disposed of

Closure Of Thane [Member] | Certain Items [Member]

Restructuring charges

$ 14

2009 Global Restructuring [Member] | Certain Items [Member]

Restructuring charges

Environmental reserves and legal settlements

$ 2

Colombia [Member]

$ 3

[1]	Equity in net income of affiliated companies is included in segment EBIT and is removed from Unallocated and Other to reconcile to segment EBIT.
[2]	Unallocated corporate costs are not controlled by the segments and primarily benefit corporate interests.
[3]	Foreign currency transactions and other (losses) income, net consists principally of gains (losses) arising from foreign currency transactions, net of other foreign currency risk management activities, and the profit related to the corporate adjustment for unearned revenue. Additionally, for both the three and nine months ended June 30, 2011, this amount included a $3 million charge related to a change in the net worth tax regulations in Colombia. For the nine months ended June 30, 2011, this amount also includes $3 million related to a portion of the benefit from a legal judgment.
[4]	Certain items are items that management does not consider to be representative of segment results and they are, therefore, excluded from segment EBIT. Certain items for both three and nine months ended June 30, 2011 primarily include charges for global restructuring activities discussed in Note H. Certain items for the three months ended June 30, 2010 include charges of $14 million related to the global restructuring activities discussed in Note H as well as $1 million related to environmental reserves and legal settlements. Certain items for the first nine months of fiscal 2010 include $38 million related to global restructuring activities, a $2 million long-lived asset impairment of land related to a former carbon black site, and $2 million for environmental reserves and legal settlements. These charges were partially offset by $1 million recovered from an investment previously impaired.

Financial Information By Segment (Schedule Of Segment Comprised Of Performance Products And Fumed Metal Oxides Businesses) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Performance Products [Member]
Performance segment sales	$ 173	$ 137	$ 464	$ 401
Fumed Metal Oxides [Member]
Performance segment sales	67	63	188	186
Total Performance Segment [Member]
Performance segment sales	$ 240	$ 200	$ 652	$ 587

Financial Information By Segment (Schedule Of Segment Comprised Of Inkjet Colorants, Aerogel Businesses, And Superior MicroPowders) (Details) - USD ($)
$ in Millions

3 Months Ended

9 Months Ended

Jun. 30, 2011

Jun. 30, 2010

Jun. 30, 2011

Jun. 30, 2010

Inkjet Colorants [Member]

$ 20

$ 15

$ 50

$ 43

Aerogel [Member]

Superior MicroPowders [Member]

New Business Segment [Member]