X0306 4 2017-12-20 0 0000353569 QUIDEL CORP /DE/ QDEL 0001021412 SCHULER JACK W 12544 HIGH BLUFF DRIVE, SUITE 200 SAN DIEGO CA 92130 1 0 1 0 Common Stock 2017-12-20 4 S 0 3500 44.40 D 3365553 D Common Stock 2017-12-21 4 S 0 500 46.00 D 3365053 D The weighted average sale price for these transactions was $44.40 per share, with a range of $43.00 to $46.00. Upon request, the Reporting Person hereby undertakes to provide to staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder, the full information regarding the number of shares sold at each separate price. The weighted average sale price for these transactions was $46.00 per share, with a range of $46.00 to $46.02. Upon request, the Reporting Person hereby undertakes to provide to staff of the U.S. Securities and Exchange Commission, the Issuer, or a security holder, the full information regarding the number of shares sold at each separate price. 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, 1,053,628 shares are held indirectly by the Schuler Family Foundation and 523,524 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, the trusts for the benefit of his children, except to the extent of his pecuniary interest, if any. All transactions reported herein were effected pursuant to a pre-established 10b5-1 trading plan established by The Schuler Grandchildren's LLC. Robert J. Bujarski, attorney-in-fact for Jack W. Schuler 2017-12-22