X0306 4 2014-05-28 0 0000791908 XOMA Corp XOMA 0001210905 RUBIN PAUL D C/O XOMA CORPORATION 2910 SEVENTH STREET BERKELEY CA 94710 0 1 0 0 Sr. VP Clinical Dev. & CMO Common Shares 2014-05-28 4 M 0 4667 0 A 85386 D Common Shares 2014-05-28 4 S 0 1785 4.22 D 83601 D Common Shares 5310 I by 401(k) Restricted Stock Units 0 2014-05-28 4 M 0 4667 0 D 2013-05-28 2015-05-28 Common Shares 4667 4666 D These restricted stock units are scheduled to vest in substantially equal installments annually over three years, with the first installment vesting on May 28, 2013. Each restricted stock unit represents the right to receive, upon vesting, one share of common stock. This nondiscretionary transaction represents the vesting of restricted stock units as shares of common stock. Shares sold on the open market to satisfy the minimum amount of taxes required to be withheld in connection with the vesting of the shares in a non-discretionary transaction pursuant to the reporting person's agreement under the Company's equity incentive plan. By: Russell J. Wood For: Paul D. Rubin 2014-05-29