CABOT CORP — Director's Dealing 2005

Jan 4, 2005

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2004-12-31

Reporting Person: CLARKESON JOHN S (Director)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2004-12-31	Phantom Stock Units	$0	A	243.02	Acquired	1988-08-08	Common stock (243.02)	Direct

Footnotes

F1: 1 for 1

F2: Immediately exercisable

F3: The shares of phantom stock become payable in monthly cash installments upon the reporting person's termination of service as a director.

F4: On November 11, 2004, Cabot's Board of Directors declared a dividend of $.16 per share on Cabot common stock, payable on December 10, 2004 to all holders of record of common stock on November 26, 2004. Mr. Clarkeson received a dividend on his phantom stock units totalling $702.58, which was immediately reinvested in phantom stock units at a price of $36.52 per share. As a result, 19.24 phantom stock units were allocated to Mr. Clarkeson on December 10, 2004.