X0306 4 2016-11-16 0 0001302573 OncoMed Pharmaceuticals Inc OMED 0001553333 Hoey Timothy C/O ONCOMED PHARMACEUTICALS, INC. 800 CHESAPEAKE DRIVE REDWOOD CITY CA 94063 0 1 0 0 SVP, Cancer Biology & Co-CSO Common Stock 2016-11-16 4 M 0 12500 1.43 A 73479 D Common Stock 2016-11-16 4 S 0 12500 9.8887 D 60979 D Stock Option (Right to Buy) 1.43 2016-11-16 4 M 0 12500 0.00 D 2017-01-10 Common Stock 12500 12763 D Transaction made pursuant to a 10b5-1 trading plan adopted by the Reporting Person on September 21, 2016. Includes 12,500 restricted stock units. The Reporting Person is entitled to receive one (1) share of common stock for each one (1) restricted stock unit. This transaction was executed in multiple trades in prices ranging from $9.65 to $10.05, inclusive. The price reported in Column 4 above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide to the Securities and Exchange Commission staff, the Issuer, or a security holder of the Issuer, upon request, full information regarding the number of shares sold at each respective price within the range set forth in this footnote. The option is fully vested and exercisable, subject to a limitation of 175,438 shares that can be issued to a single grantee in a 12-month period upon the exercise of awards under the Issuer's 2004 Stock Incentive Plan. /s/ Alicia J. Hager, Attorney-in-Fact for Timothy Hoey 2016-11-18