X0306 4 2021-12-16 0 0001626878 XBiotech Inc. XBIT 0001211462 MCKENZIE W THORPE 832 GEORGIA AVENUE SUITE 1100 CHATTANOOGA TN 37402 1 0 1 0 Common Stock 2021-12-16 4 M 0 250000 10.00 A 2810964 D Common Stock 2021-12-16 4 F 0 213493 11.71 D 2597471 D Stock Option 10.00 2021-12-16 4 M 0 250000 0.00 D 2011-12-31 2021-12-30 Common Stock 250000 320000 D Represents a "net exercise" of outstanding stock options. The reporting person received 36,507 shares of common stock on net exercise of option to purchase 250,000 shares of common stock. The Company withheld 213,493 shares of common stock underlying the option for payment of the exercise price using the closing stock price on December 16, 2021 of $11.71, pursuant to the terms of the 2005 Equity Incentive Plan. /s/Queena Han under Power of Attorney for W. Thorpe McKenzie 2022-01-13