CABOT CORP — Director's Dealing 2007

Jan 5, 2007

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2007-01-03

Reporting Person: ENRIQUEZ CABOT JUAN (Director)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2007-01-03	Phantom stock	$	I	2261.6297	Acquired		Common stock (2261.6297)	Direct

Footnotes

F1: Each share of phantom stock is the economic equivalent of one share of Cabot common stock.

F2: Immediately exercisable.

F3: Shares of phantom stock are payable in cash following the reporting person's termination of service as a director, and may be transferred into an alternative investment account.

F4: For calendar year 2007, Mr. Enriquez-Cabot elected to change the earnings measure used to measure and credit notional earnings to compensation he has elected to defer under the Cabot Corporation Deferred Compensation Plan from the Moody's Corporate Bond Rate to phantom stock units. Under the terms of the Plan, when such a change is made, the deferred cash earnings in the director's account are converted to phantom stock units based on the fair market value of Cabot common stock on the effective date of the election. The closing price of Cabot's common stock on January 3, 2007 (the effective date of the election) was $44.21.