X0306 4 2021-03-30 0 0000353569 QUIDEL CORP /DE/ QDEL 0001812662 Ferenczy William J. 9975 SUMMERS RIDGE ROAD SAN DIEGO CA 92121 0 1 0 0 SVP, Cardio/Metabolic Unit Common Stock 2021-03-30 4 M 0 434 0.00 A 5540 D Common Stock 2021-03-30 4 F 0 216 126.39 D 5324 D Restricted Stock Units 2021-03-30 4 M 0 434 0.00 D Common Stock 434 1302 D Reflects release of restricted stock units that were previously reported on a Form 4. Disposition of shares, as set forth above, was in connection with the Issuer's withholding of common shares to satisfy tax withholding obligations related to the issuance of common shares upon release of restricted stock units. Restricted stock units convert into common stock on a one-for-one basis. 434 shares vested on 03/30/2021; 434 shares will vest on 03/30/2022; 434 shares will vest on 03/30/2023; and 434 shares will vest on 03/30/2024 Phillip Askim, attorney-in-fact for William J. Ferenczy 2021-04-01