Xencor stockholders elect all seven directors and approve 2023 Equity Incentive Plan at annual meeting

Proposal 2. Ratification of the Selection of Independent Registered Public Accounting Firm The Company’s stockholders ratified the selection by the Audit Committee of the Board of Directors of RSM US LLP as its independent registered public accounting firm for the fiscal year ending December 31, 2023. The final voting results are as follows: Broker Votes for Votes Against Abstentions Non-Votes 57,762,046 582,716 6,532 -

Proposal 1. Election of Directors The Company’s stockholders elected the seven persons listed below as directors, each to serve until the 2024 Annual Meeting of Stockholders and until their successors are duly elected and qualified. The final voting results are as follows: Votes Broker Votes for Withheld Non-Votes Dr. Bassil I. Dahiyat 54,034,880 1,635,439 2,680,975 Dr. Ellen G. Feigal 53,709,086 1,961,233 2,680,975 Dr. Kevin C. Gorman 54,022,790 1,647,529 2,680,975 Mr. Kurt A. Gustafson 53,917,267 1,753,052 2,680,975 Dr. A. Bruce Montgomery 53,973,899 1,696,420 2,680,975 Mr. Richard J. Ranieri 53,792,814 1,877,505 2,680,975 Ms. Dagmar Rosa-Bjorkeson 44,326,023 11,344,296 2,680,975

Proposal 5. Advisory Vote on the Frequency of Future Non-Binding Advisory Stockholder Votes on the Compensation of the Company’s Named Executive Officers The Company’s stockholders approved, on an advisory (non-binding) basis, "one year" for the frequency of future advisory stockholder votes on the compensation of its named executive officers. The final voting results are as follows: Broker One Year Two Year Three Year Abstentions Non-Votes 53,884,063 124 1,778,570 7,562 2,680,975

Proposal 3. Advisory Vote on the Compensation of the Company’s Named Executive Officers The Company’s stockholders approved, on an advisory (non-binding) basis, the compensation of its named executive officers as disclosed in the Proxy Statement. The final voting results are as follows: Broker Votes for Votes Against Abstentions Non-Votes 53,903,252 1,760,454 6,613 2,680,975

Proposal 4. Approval of the Company’s 2023 Equity Incentive Plan The Company’s stockholders approved the Company’s 2023 Equity Incentive Plan. The final voting results are as follows: Broker Votes for Votes Against Abstentions Non-Votes 45,680,668 9,952,360 37,292 2,680,975