X0306 4 2020-05-28 0 0001708493 Harpoon Therapeutics, Inc. HARP 0001247851 HUNT RONALD C/O NEW LEAF VENTURES 7 TIMES SQUARE, SUITE 3502 NEW YORK NY 10036 1 0 1 0 Director Stock Option (Right to Buy) 20.59 2020-05-28 4 A 0 10167 0.00 A 2030-05-27 Common Stock 10167 10167 D Director Stock Option (Right to Buy) 20.59 2020-05-28 4 A 0 4906 0.00 A 2030-05-27 Common Stock 4906 4906 D The stock option will fully vest and become exercisable on May 28, 2021, subject to the continuous service of the Reporting Person with the Issuer on such date. The stock option vests and becomes exercisable as to 25% of the shares subject to the option on the last day of each calendar quarter following the grant date of May 28, 2020 (on June 30, 2020, September 30, 2020, December 31, 2020, and March 31, 2021), subject to the continuous service of the Reporting Person on each vesting date. /s/ Ronald Hunt by Christopher Whitmore, Attorney-in-Fact 2020-06-01