Xencor Inc

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrantx

Filed by a Party other than the Registranto

Check the appropriate box:

XENCOR, INC.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

April 23, 2025

Fellow stockholder,

Xencor is a clinical development-stage biotechnology company advancing cutting-edge XmAb® engineered antibodies for patients affected by cancer and autoimmune disease. The plug-and-play nature of our XmAb Fc domains and our protein engineering expertise have enabled a broad pipeline of antibody-based drug candidates being developed for patients with high unmet clinical needs. We employ a focused approach to our research and development to provide best-in-class potential, with a long-term goal of commercializing our own medicines.

In September 2024, we presented a refreshed and focused clinical pipeline that draws on our exceptional strengths at engineering proteins and solving complex biological problems. We believe that the evolution of our pipeline moves us toward our strengths while minimizing biological uncertainty. Now in 2025, we are focused on advancing a pipeline of targeted T-cell engaging bispecific antibodies, such as XmAb819 (ENPP3 x CD3) and XmAb541 (CLDN6 x CD3), which we believe hold great potential for the treatment of patients with cancer, and plamotamab (CD20 x CD3) and XmAb657 (CD19 x CD3), which are designed to deplete autoreactive B cells, a validated approach for improving the outcomes of patients with autoimmune diseases.

An additional pillar of our pipeline is our set of two programs targeting the cytokine TL1A, where recent clinical evidence has validated TL1A as a key pathway in inflammatory bowel disease (IBD). XmAb942 is a high potency, extended half-life anti-TL1A antibody that may solve several liabilities presented by the first-generation anti-TL1A molecules. And our follow-on TL1A x IL-23p19 bispecific antibody could be a first-in-class molecule that in a single drug product could shut down two important inflammatory signaling pathways in IBD and could be a potentially transformative medicine for patients and clinicians, while avoiding the complexity of dosing two separate drugs. XmAb819, XmAb541, and XmAb942 are currently enrolling subjects into Phase 1 clinical studies, and we anticipate initiating a Phase 1b/2a study of plamotamab in patients with rheumatoid arthritis in the first half of 2025, followed by initiations during the second half of the year of a first-in-human study of XmAb657. XmAb942 is expected to enter a Phase 2 study in ulcerative colitis, the most common type of IBD, before the end of 2025.

We look forward to further progress across our partnered pipeline, with multiple candidates now being evaluated in or soon entering Phase 3 studies. We ended 2024 with cash, cash equivalents and marketable securities of $706.7 million, and under our current operating plans, we believe we can reach meaningful clinical decision points for all our active programs, focusing our resources on what we believe to be our biggest value drivers.

At this upcoming annual meeting, we are asking for stockholders to vote FOR the proposed amendment and restatement of our 2023 Equity Incentive Plan to increase the authorized shares reserved for issuance thereunder. Xencor’s future success depends on the ability to attract, retain and motivate highly qualified individuals across our entire organization, as competition for talent in the oncology and autoimmune fields of the biotechnology industry is expected to remain exceptionally strong. Our request for additional shares represents approximately 4.2% of our outstanding shares as of March 31, 2025, and is designed to last one year, and our research indicates that this is in line with other companies in the biotechnology industry. We believe our request is reasonable and necessary, taking a holistic and industry-based approach to evaluating equity proposals.

We appreciate your perspective. You are invited and most welcome to join us at our 2025 Annual Meeting of Stockholders on Thursday, June 12, 2025 at 1:00 p.m. PT at our laboratories and headquarters in Pasadena, California. As always, please reach out to our investor relations personnel to help increase your understanding of our business strategy and corporate governance practices.

Bassil I. Dahiyat, Ph.D.

President, Chief Executive Officer and Director

XENCOR, INC.

465 North Halstead Street, Suite 200

Pasadena, CA 91107

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held On June 12, 2025

Dear Stockholder:

You are cordially invited to attend the 2025 Annual Meeting of Stockholders of Xencor, Inc., a Delaware corporation (the “Company”) to be held on Thursday, June 12, 2025 at 1:00 p.m. Pacific Time at the Company’s headquarters, 465 North Halstead Street, Suite 200, Pasadena, California 91107. We are holding the meeting for the following purposes:

1. To elect the eight nominees to the Board of Directors named in the accompanying Proxy Statement to serve until the next annual meeting and until their successors are duly elected and qualified;

2. To ratify the selection by the Audit Committee of the Board of Directors of KPMG LLP as the independent registered public accounting firm of the Company for its fiscal year ending December 31, 2025;

3. To approve the proposed amendment and restatement of the Company's 2023 Equity Incentive Plan to increase the number of authorized shares reserved for issuance thereunder by 3,000,000 shares;

4. To approve, on an advisory (non-binding) basis, the compensation of the Company’s named executive officers, as disclosed in the accompanying Proxy Statement; and

5. To conduct any other business properly brought before the meeting or any adjournments or postponements thereof.

These items of business are more fully described in the Proxy Statement accompanying this Notice (the “Proxy Statement”).

The record date for the annual meeting is April 15, 2025. Only stockholders of record at the close of business on that date may vote at the meeting or any adjournment thereof. This Notice is being mailed to all stockholders of record entitled to vote at the annual meeting on or about April 24, 2025.

Our Board of Directors recommends that you vote FOR the election of each of the director nominees and FOR Proposals 2, 3 and 4.

If we decide to make any change in the date, time or location, or to hold the annual meeting virtually by remote communication, an announcement of such changes will be made through a press release that will also be filed with the Securities and Exchange Commission as additional proxy materials and we will post details on our website athttps://investors.xencor.com. Please check our website in advance of the date of the annual meeting if you are planning to attend in person. If we elect to hold a virtual meeting, this will not have any impact on your ability to vote by proxy using the enclosed proxy card, vote by proxy on the internet or vote by proxy over the telephone, each as explained in the Proxy Statement. As always, we encourage you to vote your shares prior to the annual meeting.

April 23, 2025

You are cordially invited to attend the annual meeting. Whether or not you expect to attend the meeting, please complete, date, sign and return the proxy mailed to you as promptly as possible in order to ensure your representation at the meeting. Even if you have voted by proxy, you may still vote if you attend the meeting. Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to vote at the meeting, you must obtain a proxy issued in your name from that record holder.

Important Notice Regarding the Availability of Proxy Materials for the Stockholders Meeting to Be Held on June 12, 2025: Our Notice of Annual Meeting of Stockholders, Proxy Statement and Annual Report on Form 10-K for the fiscal year ended December 31, 2024 will be available at www.proxydocs.com/XNCR.

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