X0306 4 2021-01-29 0 0000353569 QUIDEL CORP /DE/ QDEL 0001277462 GIBSON KAREN 9975 SUMMERS RIDGE ROAD SAN DIEJO CA 92121 0 1 0 0 SVP, Digital Health Common Stock 2021-01-29 4 A 0 2970 0.00 A 4440 D Common Stock 2021-01-29 4 F 0 1126 250.97 D 3314 D Restricted Stock Units 2021-01-29 4 M 0 2970 0.00 D Common Stock 2970 0 D Reflects release of restricted stock units that were previously reported on a Form 4. The amount of securities beneficially owned following this transaction include an additional 277 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. Restricted stock units convert into common stock on a one-for-one basis. 2,970 shares vested on the third anniversary date of the grant date, January 29, 2021 Robert J. Bujarski, attorney-in-fact for Karen C. Gibson 2021-02-02