X0202 4 2007-05-19 0 0000353569 QUIDEL CORP /DE/ QDEL 0001301366 Mason Caren L 10165 MCKELLAR COURT SAN DIEGO CA 92121 1 1 0 0 President and CEO Common Stock 2007-05-19 4 F 0 17986 13.61 D 196084 D Disposition of shares, as set forth above, was in connection with the Company's withholding of stock to satisfy tax withholding obligations related to the lapse of restrictions on Reporting Person's restricted stock award. Robert J. Bujarski, attorney-in-fact for Caren L. Mason 2007-05-22