X0306 4 2017-12-01 0 0001435049 ADURO BIOTECH, INC. ADRO 0001635616 Brockstedt Dirk G. C/O ADURO BIOTECH, INC. 740 HEINZ AVENUE BERKELEY CA 94710 0 1 0 0 EVP of Research and Dev. Common Stock 2017-12-01 4 M 0 3956 0.52 A 77674 D Common Stock 2017-12-01 4 M 0 6044 0.52 A 83718 D Common Stock 2017-12-01 4 S 0 10000 9.3998 D 73718 D Stock Option (Right to Buy) 0.52 2017-12-01 4 M 0 3956 0.00 D 2021-10-24 Common Stock 3956 42000 D Stock Option (Right to Buy) 0.52 2017-12-01 4 M 0 6044 0.00 D 2021-10-24 Common Stock 6044 55014 D The sales reported in this Form 4 were affected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on June 12, 2017. The price reported in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $9.15 to $9.50, 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. The shares subject to the Option became fully vested and exercisable as of April 15, 2015. The shares subject to the Option are fully vested and immediately exercisable. Since the date of the Reporting Person's last ownership report, he transferred a portion of this Option to purchase 38,529 shares of the Issuer's common stock to his ex-wife pursuant to a domestic relations order. The Reporting Person no longer reports as beneficially owned any securities owned by his ex-wife. /s/ Jennifer Lew, Attorney-in-Fact 2017-12-04