Summary of Significant Accounting Policies	9 Months Ended
Sep. 30, 2015
Summary of Significant Accounting Policies
Summary of Significant Accounting Policies	1. Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited interim financial statements for Xencor, Inc. (the Company) have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information. The financial statements include all adjustments (consisting only of normal recurring adjustments) that the management of the Company believes are necessary for a fair presentation of the periods presented. These interim financial results are not necessarily indicative of the results expected for the full fiscal year or for any subsequent interim period. The accompanying unaudited interim financial statements and related notes should be read in conjunction with the audited financial statements and notes thereto included in the Company’s 2014 Annual Report on Form 10-K filed with the Securities and Exchange Commission (SEC) on February 23, 2015, as amended. Marketable Securities The Company has an investment policy that includes guidelines on acceptable investment securities, minimum credit quality, maturity parameters and concentration and diversification. The Company invests its excess cash primarily in marketable securities issued by investment grade institutions. The Company considers its marketable securities to be “available-for-sale”, as defined by authoritative guidance issued by the Financial Accounting Standards Board (FASB). These assets are carried at fair value and the unrealized gains and losses are included in accumulated other comprehensive income (loss). If a decline in the value of a marketable security in the Company’s investment portfolio is deemed to be other-than-temporary, the Company writes down the security to its current fair value and recognizes a loss as a charge against income. The Company reviews its portfolio of marketable securities, using both quantitative and qualitative factors, to determine if declines in fair value below cost are other-than-temporary. There have been no other material changes to the significant accounting policies previously disclosed in the Company’s 2014 Annual Report on Form 10-K, as amended. Sale of Additional Common Stock In March 2015, we completed the sale of 8,625,000 shares of common stock which included shares we issued pursuant to our underwriters’ exercise of their over-allotment option pursuant to a follow-on offering. We received net proceeds of $115.2 million, after underwriting discounts, commissions and estimated offering expenses. Recent Accounting Pronouncements In May 2014, the FASB issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers, which establishes principles for reporting revenue and cash flows arising from an entity’s contracts with customers. This new revenue recognition standard will replace most of the recognition guidance within the United States GAAP. In July 2015, the FASB announced that the new pronouncement will be effective for reporting periods beginning after December 15, 2017. The new pronouncement permits the use of either the retroactive or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its financial statements and related disclosures.

1. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying unaudited interim financial statements for Xencor, Inc. (the Company) have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) for interim financial information. The financial statements include all adjustments (consisting only of normal recurring adjustments) that the management of the Company believes are necessary for a fair presentation of the periods presented. These interim financial results are not necessarily indicative of the results expected for the full fiscal year or for any subsequent interim period.

The accompanying unaudited interim financial statements and related notes should be read in conjunction with the audited financial statements and notes thereto included in the Company’s 2014 Annual Report on Form 10-K filed with the Securities and Exchange Commission (SEC) on February 23, 2015, as amended.

Marketable Securities

The Company has an investment policy that includes guidelines on acceptable investment securities, minimum credit quality, maturity parameters and concentration and diversification. The Company invests its excess cash primarily in marketable securities issued by investment grade institutions. The Company considers its marketable securities to be “available-for-sale”, as defined by authoritative guidance issued by the Financial Accounting Standards Board (FASB). These assets are carried at fair value and the unrealized gains and losses are included in accumulated other comprehensive income (loss). If a decline in the value of a marketable security in the Company’s investment portfolio is deemed to be other-than-temporary, the Company writes down the security to its current fair value and recognizes a loss as a charge against income. The Company reviews its portfolio of marketable securities, using both quantitative and qualitative factors, to determine if declines in fair value below cost are other-than-temporary.

There have been no other material changes to the significant accounting policies previously disclosed in the Company’s 2014 Annual Report on Form 10-K, as amended.

Sale of Additional Common Stock

In March 2015, we completed the sale of 8,625,000 shares of common stock which included shares we issued pursuant to our underwriters’ exercise of their over-allotment option pursuant to a follow-on offering. We received net proceeds of $115.2 million, after underwriting discounts, commissions and estimated offering expenses.

Recent Accounting Pronouncements

In May 2014, the FASB issued Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers, which establishes principles for reporting revenue and cash flows arising from an entity’s contracts with customers. This new revenue recognition standard will replace most of the recognition guidance within the United States GAAP. In July 2015, the FASB announced that the new pronouncement will be effective for reporting periods beginning after December 15, 2017. The new pronouncement permits the use of either the retroactive or cumulative effect transition method. The Company is evaluating the effect that ASU 2014-09 will have on its financial statements and related disclosures.