X0306 4 2020-01-15 0000874015 IONIS PHARMACEUTICALS INC IONS 0000897667 CROOKE STANLEY T C/O IONIS PHARMACEUTICALS, INC. 2855 GAZELLE COURT CARLSBAD CA 92010 1 1 0 0 Executive Chairman of Board Common Stock 2020-01-15 2020-01-15 4 M 0 39643 0 A 109277 D Common Stock 2020-01-15 2020-01-15 4 F 0 17342 62.06 D 91935 D Common Stock 2020-01-15 2020-01-15 4 M 0 3317 0 A 8849 I By wife Common Stock 2020-01-15 2020-01-15 4 F 0 1268 62.06 D 7581 I By wife Common Stock 700391 I By trust Restricted Stock Units 2020-01-15 2020-01-15 4 A 0 62982 0 A Common Stock 62982 62982 D Restricted Stock Units 2020-01-15 2020-01-15 4 A 0 5545 0 A Common Stock 5545 5545 I By wife Restricted Stock Units 2020-01-15 2020-01-15 4 M 0 39643 0 D Common Stock 39643 72160 D Restricted Stock Units 2020-01-15 2020-01-15 4 M 0 3317 0 D Common Stock 3317 6627 I By wife Acquired pursuant to vesting and release of shares in accordance with Restricted Stock Unit awards. Shares withheld to cover the required tax withholding obligations pursuant to the Ionis Pharmaceuticals, Inc. Amended and Restated 2011 Equity Incentive Plan. Grant to reporting person of Restricted Stock Units under the Ionis Pharmaceuticals, Inc. Amended and Restated 2011 Equity Incentive Plan. Each Restricted Stock Unit represents a contingent right to receive one share of Ionis common stock, or its equivalent cash value. Restricted Stock Units vest in four equal annual installments. Upon vesting, the Restricted Stock Units will be paid out in whole shares of Ionis common stock or cash as may be determined by Ionis. Grant to reporting person's wife of Restricted Stock Units under the Ionis Pharmaceuticals, Inc. 2011 Equity Incentive Plan. /s/Patrick R. O'Neil, attorney-in-fact 2020-01-17