X0306 4 2018-08-09 0 0001326732 Xencor Inc XNCR 0001591313 Desjarlais John R C/O XENCOR, INC. 111 WEST LEMON AVENUE MONROVIA CA 91016 0 1 0 0 Sr. V.P., Research & CSO Common Stock 2018-08-09 4 M 0 35000 4.25 A 123098 D Common Stock 2018-08-09 4 S 0 20133 40.6114 D 102965 D Common Stock 2018-08-10 4 S 0 14867 40.0277 D 88098 D Stock Option (right to buy) 4.25 2018-08-09 4 M 0 35000 0.00 D 2023-09-03 Common Stock 35000 27522 D Includes the following shares acquired by the Reporting Person pursuant to the Issuer's Employee Stock Purchase Plan: 156 shares of Common Stock acquired on June 19, 2017, 159 shares of Common Stock acquired on December 10, 2017 and 107 shares of Common Stock acquired on June 8, 2018. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $40.77 to $42.00, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $40.00 to $40.0558, inclusive. The reporting person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. The stock option is fully vested and exercisable. /s/ John R. Desjarlais 2018-08-10