X0306 4/A 2013-02-25 2013-02-27 0 0000353569 QUIDEL CORP /DE/ QDEL 0001333458 Bujarski Robert Joseph 10165 MCKELLAR COURT SAN DIEGO CA 92121 0 1 0 0 SVP, General Counsel & Secy Non-Qualified Stock Option 22.21 2013-02-25 4 A 0 29605 0.00 A 2023-02-25 Common Stock 29605 29605 D Restricted Stock Units 2013-02-25 4 A 0 1350 0.00 A Common Stock 1350 1350 D 14,803 shares will vest on the second anniversary date of the grant date, February 25, 2015. 7,401 shares will vest on the third anniversary date of the grant date, February 25, 2016. 7,401 shares will vest on the fourth anniversary date of the grant date, February 25, 2017. Each restricted stock unit represents the right to receive one share of Quidel Corporation common stock. 675 shares will vest on the second anniversary date of the grant date, February 25, 2015. 337 shares will vest on the third anniversary date of the grant date, February 25, 2016. 338 shares will vest on the fourth anniversary date of the grant date, February 25, 2017. This amended Form 4 is being filed to correct the number of derivative securities acquired by the reporting person, the related amount of securities underlying the derivative securities, and the amounts that vest on the respective vesting dates. Robert J. Bujarski 2013-03-27