CABOT CORP — Director's Dealing 2008

Jan 11, 2008

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2008-01-08

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)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2008-01-08	Common Stock	P	300	$31.72	Acquired	9934600	Indirect
2008-01-08	Common Stock	P	200	$31.74	Acquired	9934800	Indirect
2008-01-08	Common Stock	P	400	$31.75	Acquired	9935200	Indirect
2008-01-08	Common Stock	P	200	$31.76	Acquired	9935400	Indirect
2008-01-08	Common Stock	P	100	$31.78	Acquired	9935500	Indirect
2008-01-08	Common Stock	P	200	$31.79	Acquired	9935700	Indirect
2008-01-09	Common Stock	P	200	$30.39	Acquired	9935900	Indirect
2008-01-09	Common Stock	P	400	$30.40	Acquired	9936300	Indirect
2008-01-09	Common Stock	P	400	$30.41	Acquired	9936700	Indirect
2008-01-09	Common Stock	P	300	$30.42	Acquired	9937000	Indirect
2008-01-09	Common Stock	P	1000	$30.43	Acquired	9938000	Indirect
2008-01-09	Common Stock	P	1200	$30.44	Acquired	9939200	Indirect
2008-01-09	Common Stock	P	700	$30.45	Acquired	9939900	Indirect
2008-01-09	Common Stock	P	1000	$30.46	Acquired	9940900	Indirect
2008-01-09	Common Stock	P	2400	$30.47	Acquired	9943300	Indirect
2008-01-09	Common Stock	P	1300	$30.48	Acquired	9944600	Indirect
2008-01-09	Common Stock	P	1600	$30.49	Acquired	9946200	Indirect
2008-01-09	Common Stock	P	1500	$30.50	Acquired	9947700	Indirect
2008-01-09	Common Stock	P	1200	$30.51	Acquired	9948900	Indirect
2008-01-09	Common Stock	P	1600	$30.52	Acquired	9950500	Indirect
2008-01-09	Common Stock	P	900	$30.53	Acquired	9951400	Indirect
2008-01-09	Common Stock	P	1700	$30.54	Acquired	9953100	Indirect
2008-01-09	Common Stock	P	1600	$30.55	Acquired	9954700	Indirect
2008-01-09	Common Stock	P	1000	$30.56	Acquired	9955700	Indirect
2008-01-09	Common Stock	P	1100	$30.57	Acquired	9956800	Indirect
2008-01-09	Common Stock	P	1000	$30.58	Acquired	9957800	Indirect
2008-01-09	Common Stock	P	400	$30.59	Acquired	9958200	Indirect
2008-01-09	Common Stock	P	500	$30.60	Acquired	9958700	Indirect
2008-01-09	Common Stock	P	600	$30.61	Acquired	9959300	Indirect
2008-01-09	Common Stock	P	600	$30.62	Acquired	9959900	Indirect

Footnotes

F1: The entities directly acquiring the shares reported on this form are SPO Partners II, L.P. ("SPO Partners"), which bought 82,600 shares, and the Elizabeth R. & William J. Patterson Foundation ("WJPFND"), which bought 2,200 shares.

F2: Due to the purchases causing this filing and related filings today, 9,568,800 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"), William E. Oberndorf ("WEO") and William J. Patterson ("WJP"), the three controlling persons of SPO Corp. 415,600 shares are owned directly by San Francisco Partners, L.P. ("SF Partners"), and may be deemed to be indirectly beneficially owned by (i) SF Advisory Partners, L.P. ("SF Advisory"), the sole general partner of SF Partners, (ii) SPO Corp., the sole general partner of SF Advisory, and (iii) JHS, WEO and WJP, the three controlling persons of SPO Corp. These shares are represented in the running total in Column 5 above, which does not include 19,400 shares held by WJPFND.

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, (iii) WEO owns 109,000 shares in his IRA, which is self-directed, and (iv) 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.