CABOT CORP — Director's Dealing 2008

Jan 8, 2008

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CABOT CORP (CBT)
CIK: 0000016040
Period of Report: 2008-01-03

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
2008-01-03	Common Stock	P	200	$31.63	Acquired	9828900	Indirect
2008-01-03	Common Stock	P	200	$31.64	Acquired	9829100	Indirect
2008-01-03	Common Stock	P	300	$31.65	Acquired	9829400	Indirect
2008-01-03	Common Stock	P	400	$31.66	Acquired	9829800	Indirect
2008-01-03	Common Stock	P	1200	$31.67	Acquired	9831000	Indirect
2008-01-03	Common Stock	P	400	$31.68	Acquired	9831400	Indirect
2008-01-03	Common Stock	P	500	$31.69	Acquired	9831900	Indirect
2008-01-03	Common Stock	P	600	$31.70	Acquired	9832500	Indirect
2008-01-03	Common Stock	P	600	$31.71	Acquired	9833100	Indirect
2008-01-03	Common Stock	P	3500	$31.72	Acquired	9836600	Indirect
2008-01-03	Common Stock	P	2100	$31.73	Acquired	9838700	Indirect
2008-01-03	Common Stock	P	9160	$31.74	Acquired	9847860	Indirect
2008-01-03	Common Stock	P	1930	$31.75	Acquired	9849790	Indirect
2008-01-03	Common Stock	P	6800	$31.76	Acquired	9856590	Indirect
2008-01-03	Common Stock	P	5100	$31.77	Acquired	9861690	Indirect
2008-01-03	Common Stock	P	2000	$31.78	Acquired	9863690	Indirect
2008-01-03	Common Stock	P	6900	$31.79	Acquired	9870590	Indirect
2008-01-03	Common Stock	P	6000	$31.80	Acquired	9876590	Indirect
2008-01-03	Common Stock	P	3400	$31.81	Acquired	9879990	Indirect
2008-01-03	Common Stock	P	1100	$31.82	Acquired	9881090	Indirect
2008-01-03	Common Stock	P	1600	$31.83	Acquired	9882690	Indirect
2008-01-03	Common Stock	P	700	$31.84	Acquired	9883390	Indirect
2008-01-03	Common Stock	P	2307	$31.85	Acquired	9885697	Indirect
2008-01-03	Common Stock	P	1000	$31.86	Acquired	9886697	Indirect
2008-01-03	Common Stock	P	2603	$31.87	Acquired	9889300	Indirect
2008-01-03	Common Stock	P	400	$31.88	Acquired	9889700	Indirect
2008-01-03	Common Stock	P	500	$31.89	Acquired	9890200	Indirect
2008-01-03	Common Stock	P	100	$31.90	Acquired	9890300	Indirect
2008-01-03	Common Stock	P	200	$31.91	Acquired	9890500	Indirect
2008-01-03	Common Stock	P	100	$31.92	Acquired	9890600	Indirect

Footnotes

F1: The entities directly acquiring the shares reported on this form are SPO Partners II, L.P. ("SPO Partners"), which bought 73,100 shares, and the Elizabeth R. & William J. Patterson Foundation ("WJPFND"), which bought 2,000 shares.

F2: Due to the purchases causing this filing and related filings today, 9,486,200 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 17,200 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.