CABOT CORP — Director's Dealing 2009

Jun 2, 2009

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2009-05-28

Reporting Person: SPO ADVISORY CORP (10% Owner)
Reporting Person: SPO ADVISORY PARTNERS LP (10% Owner)
Reporting Person: SPO PARTNERS II LP (10% Owner)
Reporting Person: Elizabeth R. & William J. Patterson Foundation (10% Owner)
Reporting Person: SCULLY JOHN H (10% Owner)
Reporting Person: OBERNDORF WILLIAM E (10% Owner)
Reporting Person: PATTERSON WILLIAM J (10% Owner)
Reporting Person: MCDERMOTT EDWARD H (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2009-05-28	Common Stock	S	3800000	$15.60	Disposed	5913400	Indirect

Footnotes

F1: The entities and individuals directly selling the shares reported on this form are SPO Partners II, L.P. ("SPO Partners"), which sold 3,749,200 shares, William E. Oberndorf ("WEO"), who sold 42,300 shares and the Elizabeth R. & William J. Patterson Foundation ("WJPFND"), which sold 8,500 shares.

F2: Due to the sales causing this filing, 5,913,400 shares are owned directly by SPO Partners, and may be deemed to be indirectly beneficially owned by (i) SPO Advisory Partners, L.P. ("SPO Advisory"), the sole general partner of SPO Partners, (ii) SPO Advisory Corp. ("SPO Corp."), the sole general partner of SPO Advisory, and (iii) John H. Scully ("JHS"), WEO, William J. Patterson ("WJP") and Edward H. McDermott ("EHM"), the four controlling persons of SPO Corp. These shares are represented in the running total in Column 5 above. Additionally, due to these sales, WEO owns 66,700 shares in his IRA, which is self-directed and WJPFND owns 13,400 shares of the issuer's common stock.

F3: Additionally, (i) 333,650 shares of the issuer's common stock may be deemed to be indirectly beneficially owned by WEO solely in his capacity as a trustee for the William and Susan Oberndorf Trust, dated 10/15/98 ("Oberndorf Trust"), (ii) 100,000 shares may be deemed to be indirectly beneficially owned by WEO solely in his capacity as general partner of Oberndorf Family Partners, a California limited partnership and (iii) 10,000 shares may be deemed to be indirectly beneficially owned by WEO solely in his capacity as trustee for the accounts of his two children, Peter C. Oberndorf & William Ernst Oberndorf.