CABOT CORP — Director's Dealing 2003

Oct 2, 2003

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2003-09-30

Reporting Person: CLARKESON JOHN S (Director)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2003-09-30	Phantom Stock Units	$0	A	448.97	Acquired	1988-08-08	Common stock (448.97)	Direct

Footnotes

F1: 1 for 1

F2: Immediately excercisable

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 July 11, 2003, Cabot's Board of Directors declared a dividend of $.15 per share on Cabot common stock, payable on September 12, 2003 to all holders of record of common stock on August 29, 2003. Mr. Clarkeson received a dividend on his phantom stock units totalling $387.15, which was immediately reinvested in phantom stock units at a price of $30.48 per share. As a result, 12.70 phantom stock units were allocated to Mr. Clarkeson on September 12, 2003.