CABOT CORP — Director's Dealing 2009

May 11, 2009

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2009-05-07

Reporting Person: Kelly James Patrick (Vice President and Controller)

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2009-05-07	Employee Stock Option (Right to Buy)	$16.90	A	16300	Acquired	2019-05-06	Common Stock (16300)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	9112.8098	Indirect

Footnotes

F1: Reflects retirement plan contributions by the Corporation, including contributions that have occurred since the date of the reporting person's last ownership report.

F2: The option vests over a three year period as follows: 30% on May 7, 2010, 30% on May 7, 2011 and 40% on May 7, 2012.