CABOT CORP — Director's Dealing 2004

Apr 1, 2004

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2004-03-31

Reporting Person: CLARKESON JOHN S (Director)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2004-03-31	Phantom Stock Units	$0	A	390.24	Acquired	1988-08-08	Common stock (390.24)	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 January 9, 2004, Cabot's Board of Directors declared a dividend of $.15 per share on Cabot common stock, payable on March 12, 2004 to all holders of record of common stock on February 27, 2004. Mr. Clarkeson received a dividend on his phantom stock units totalling $502.80, which was immediately reinvested in phantom stock units at a price of $33.40 per share. As a result, 15.05 phantom stock units were allocated to Mr. Clarkeson on March 12, 2004.