X0305 4 2012-05-10 0 0000353569 QUIDEL CORP /DE/ QDEL 0001021412 SCHULER JACK W 10165 MCKELLAR COURT SAN DIEGO CA 92121 1 0 0 0 Common Stock 2012-05-10 4 M 0 2600 0.00 A 3315053 D Restrict Stock Units (Equity Grant) 2012-05-10 4 M 0 2600 0.00 D Common Stock 2600 0 D Reflects vesting of prior restricted stock units, which were previously reported on a Form 4. In addition to the shares reported on this Form 4 as directly owned by the Reporting Person, 65,000 shares are held indirectly by the Reporting Person's spouse, 441,961 shares are held indirectly by the Schuler Family Foundation and 683,843 shares are held indirectly by trusts for the benefit of the Reporting Person's children. The Reporting Person disclaims all beneficial ownership of the shares owned by his spouse and the trusts for the benefit of his children, except to the extent of his pecuniary interset, if any. Each restricted stock unit represents a right to receive one share of common stock. The restricted stock units vested in full on May 10, 2012. Robert J. Bujarski, attorney-in-fact for Jack W. Schuler 2012-05-14