X0306 4 2022-03-30 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 2022-03-30 4 A 0 434 0.00 A 8834 D Common Stock 2022-03-30 4 F 0 151 112.80 D 8683 D Restricted Stock Units 2022-03-30 4 M 0 434 0.00 D Common Stock 434 868 D Reflects release of restricted stock units that were previously reported on a Form 3. The amount of securities beneficially owned following this transaction include an additional 165 shares due to the Reporting Person's purchase of shares pursuant to the Issuer's Employee Stock Purchase Plan. 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. Each restricted stock unit represents the right to receive one (1) share of Quidel Corporation common stock. 434 shares vested on 03/30/2021; 434 shares vested on 03/30/2022; 434 shares will vest on 03/30/2023; and 434 shares will vest on 03/30/2024. Robert J. Bujarski, attorney-in-fact for William J. Ferenczy 2022-04-01