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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934

Date of Report (Date of Earliest Event Reported):		September 21, 2005

Cabot Corporation
__________________________________________
(Exact name of registrant as specified in its charter)

Delaware	1-5667	04-2271897
_____________________ (State or other jurisdiction	_____________ (Commission	______________ (I.R.S. Employer
of incorporation)	File Number)	Identification No.)
Two Seaport Lane, Suite 1300, Boston, Massachusetts		02210-2019
_________________________________ (Address of principal executive offices)		___________ (Zip Code)

Registrant’s telephone number, including area code:		617-345-0100

Not Applicable
______________________________________________
Former name or former address, if changed since last report

 

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

[  ]  Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
[  ]  Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)
[  ]  Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))
[  ]  Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

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Item 8.01 Other Events.

On September 21, 2005, Cabot Corporation ("Cabot") issued a press release announcing that Cabot's wholly-owned subsidiary, Cabot International Capital Corporation ("CICC"), has entered into an agreement with Showa Denko K.K. pursuant to which CICC will become the sole owner of Showa Cabot K.K., a 50/50 joint venture between Cabot and Showa Denko. The text of the press release is attached as Exhibit 99 to this Current Report on Form 8-K.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

		Cabot Corporation
September 21, 2005		By:		/s/ William J. Brady
				Name: William J. Brady
				Title: Executive Vice President

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Exhibit Index

Exhibit No.		Description
99		Press release issued by Cabot Corporation ("Cabot") on September 21, 2005 announcing that Cabot's wholly-owned subsidiary, Cabot International Capital Corporation ("CICC"), has entered into an agreement with Showa Denko K.K. pursuant to which CICC will become the sole owner of Showa Cabot K.K., a 50/50 joint venture between Cabot and Showa Denko.

susannah_robinson@cabot-corp.com

CABOT CORPORATION AND SHOWA K.K. ANNOUNCE AGREEMENT
Cabot unit to become 100% owner of carbon black joint venture

(Tokyo, Japan and Boston, MA, USA)— September 21, 2005— Cabot Corporation (NYSE: CBT) announced today that its wholly owned subsidiary, Cabot International Capital Corporation (CICC), has entered into an agreement with Showa Denko K.K. pursuant to which CICC will become the sole owner of Showa Cabot K.K., a 50:50 joint venture between Cabot and Showa Denko. Showa Cabot has operated a carbon black business in Japan since 1978.

Takeshi Mimura, Showa Cabot’s President, will continue to lead Showa Cabot. Following the transaction, which is expected to close in November 2005, Showa Cabot will be renamed Cabot Japan K.K.

“This transaction will allow us to strengthen our relationships and technical ties with the growing and influential Japanese global tire and industrial products companies,” said Bill Brady, Executive Vice President and General Manager of Cabot’s carbon black business.

“We have had a long and mutually beneficial relationship with Showa Denko K.K., and we are very pleased to enter into this transaction with them,” said Kennett Burnes, Chairman and Chief Executive Officer of Cabot.

Cabot Corporation is a global specialty chemicals and materials company headquartered in Boston, Massachusetts, USA. Cabot’s major products are carbon black, fumed silica, inkjet colorants, capacitor materials, and cesium formate drilling fluids. The website address is: www.cabot-corp.com.

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