X0306 4 2013-08-14 0 0000791908 XOMA Corp XOMA 0001416176 Varian John C/O XOMA CORPORATION 2910 SEVENTH STREET BERKELEY CA 94710 1 1 0 0 Director and CEO Common Shares 2013-08-14 4 S 0 51647 3.8612 D 8432 D Common Shares 2013-08-14 4 M 0 94574 0 A 103006 D Common Shares 2013-08-15 4 M 0 10000 1.24 A 113006 D Common Shares 2013-08-15 4 S 0 10000 3.9212 D 103006 D Common Shares 13797 I by 401(k) Incentive Share Option (right to buy) 1.24 2013-08-15 4 M 0 10000 1.24 D 2022-01-04 Common Shares 10000 290392 D Restricted Stock Units 0 2013-08-14 4 M 0 94574 0 D 2015-08-14 Common Shares 94574 189147 D Non discretionary open market sale of shares to satisfy the minimum amount of taxes required to be withheld in connection with the vesting of Restricted Stock Units pursuant to the award. This transaction was executed in multiple trades ranging at prices from $3.86 to $3.94.The price reported reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the Issuer or a security holder of the Issuer full information regarding the number of shares and prices at which the transactions were effected. This transaction was made pursuant to Rule 10b5-1 trading plan adopted by the reporting person on 3/20/2013. This transaction was executed in multiple trades ranging at prices from $3.85 to $3.97.The price reported reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the Issuer or a security holder of the Issuer full information regarding the number of shares and prices at which the transactions were effected. Incentive Stock Option exercisable in conjunction with matching Non-Qualified Stock Option as to forty-eight (48) equal and consecutive monthly installments beginning one month after the date of grant. These restricted stock units are scheduled to vest in substantially equal installments annually over three years, with the first installment vesting on August 14, 2013. By: Fred Kurland For: John Varian 2013-08-16