UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): November 30, 2016

XENCOR, INC.

(Exact name of registrant as specified in its charter)

111 West Lemon Avenue

Monrovia, California 91016

(Address of principal executive offices and zip code)

Registrant’s telephone number, including area code: (626) 305-5900

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o                 Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o                 Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o                 Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o                 Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 1.01      Entry Into a Material Definitive Agreement.

On November 30, 2016, we entered into an underwriting agreement (the “Underwriting Agreement”) with Leerink Partners LLC as representative of the several underwriters named therein (the “Underwriters”), relating to the issuance and sale of 4,585,000 shares of our common stock, par value $0.01 per share. The price to the public in this offering was $24.00 per share. The net proceeds to us from the sale of 4,585,000 shares in this offering are expected to be approximately $104.0 million, after deducting underwriting discounts and commissions and other estimated offering expenses payable by us. The offering is scheduled to close on or about December 6, 2016, subject to customary closing conditions. In addition, under the terms of the Underwriting Agreement, we granted the Underwriters an option, exercisable for 30 days, to purchase up to 687,750 additional shares of common stock.

The Underwriting Agreement contains customary representations, warranties and agreements by us, customary conditions to closing, indemnification obligations of Xencor, Inc. and the Underwriters, including for liabilities under the Securities Act of 1933, as amended, other obligations of the parties and termination provisions. The representations, warranties and covenants contained in the Underwriting Agreement were made only for purposes of such agreement and as of specific dates, were solely for the benefit of the parties to such agreement, and may be subject to limitations agreed upon by the contracting parties.

The offering was made pursuant to our effective registration statement on Form S-3 (Registration Statement No. 333-213700) previously filed with the Securities and Exchange Commission (“SEC”) and a related prospectus supplement and accompanying prospectus. The Underwriting Agreement is filed as Exhibit 1.1 to this report and the foregoing description of the terms of the Underwriting Agreement is qualified in its entirety by reference to such exhibit. A copy of the opinion of Cooley LLP relating to the legality of the issuance and sale of the shares in the offering is attached as Exhibit 5.1 hereto.

On November 30, 2016, we issued a press release announcing that we had commenced the offering. On December 1, 2016, we issued a press release announcing that we had priced the offering. Copies of these press releases are attached as Exhibits 99.1 and 99.2 hereto, respectively.

Item 9.01      Financial Statements and Exhibits.

(d) Exhibits

Forward-Looking Statements

Certain statements contained in this report, other than statements of fact that are independently verifiable at the date hereof, may constitute forward-looking information and forward-looking statements (collectively “forward-looking statements” within the meaning of applicable securities laws). Such statements, based as they are on the current expectations of management of Xencor and upon what management believes to be reasonable assumptions based on information currently available to it, inherently involve numerous risks and uncertainties, known and unknown, many of which are beyond Xencor’s control. Such statements can usually be identified by the use of words such as “may”, “would”, “believe”, “intend”, “plan”, “anticipate”, “estimate”, “expected” and other similar terminology, or state that certain actions, events or results “may” or “would” be taken, occur or be achieved. Forward-looking statements in this report include, but are not limited to, statements related to Xencor’s expectations regarding the completion, timing and size of its public offering of common stock, and the expected net proceeds from the offering.

Whether actual results and developments will conform with our expectations and predictions is subject to a number of risks, assumptions and uncertainties, many of which are beyond our control, and the effects of which can be difficult to predict. These risks include those associated with market risks and uncertainties and the satisfaction of customary closing conditions for an offering of securities, as well as those inherent in drug development, whether Xencor will be able to obtain financing when needed or on favorable terms, and other risks described in Xencor’s filings with the SEC. In evaluating any forward-looking statements in this report, Xencor cautions readers not to place undue reliance on any forward-looking statements. Unless otherwise required by applicable securities laws, Xencor does not intend, nor does it undertake any obligation, to update or revise any forward-looking statements contained in this report to reflect subsequent information, events, results or circumstances or otherwise.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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