UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13G

(Amendment No. 11)

Under the Securities Exchange Act of 1934

Quidel Corporation 

(Name of Issuer)

Common Stock, par value $0.001 

(Title of Class of Securities)

74838J101 

(CUSIP Number)

December 31, 2013

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (the “Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

This Amendment No. 11 to Schedule 13G (this "Amendment No. 11") is being filed with respect to the Common Stock, par value $0.001 (“Common Stock”) of Quidel Corporation, a Delaware corporation (the “Issuer”), to amend the Schedule 13G filed on April 23, 2001, as previously amended by Amendment No. 1, filed on February 14, 2002, by Amendment No. 2, filed on February 12, 2003, by Amendment No. 3, filed on February 9, 2005, by Amendment No. 4, filed on February 7, 2006, by Amendment No. 5, filed on February 15, 2008, by Amendment No. 6 filed on May 20, 2009, by Amendment No. 7, filed on February 2, 2010, by Amendment No. 8, filed on February 8, 2011, by Amendment No. 9, filed on February 6, 2012, and by Amendment No. 10 filed on February 12, 2013 (as so amended, the “Schedule 13G”), in accordance with the annual amendment requirements. Capitalized terms used but not defined herein have the meaning ascribed thereto in the Schedule 13G.

Item 2(a) of the Schedule 13G is hereby amended and restated as follows:

This statement is filed by:

Item 4 of the Schedule 13G is hereby amended and restated as follows:

The percentage of shares owned is based upon 33,950,194 shares of the Issuer’s Common Stock issued and outstanding as of October 21, 2013, as set forth in the Issuer’s most recent Quarterly Report on Form 10-Q for the period ended September 30, 2013, filed with the Securities and Exchange Commission on October 25, 2013.

The beneficial ownership of the Reporting Persons as of the date of this Amendment No. 1 is set forth below. This filing and any future amendments hereto shall not be considered an admission that any Reporting Person is a beneficial owner of shares beneficially owned by any other Reporting Person named herein.

A. Larry N. Feinberg

(a) Amount beneficially owned: 3,258,457

(b) Percent of class: 9.6%

(c) Number of shares as to which such person has:

(i)    Sole power to vote or direct the vote: 50,000

(ii)   Shared power to vote or direct the vote: 3,208,457

(iii)  Sole power to dispose or direct the disposition: 50,000

(iv)  Shared power to dispose or direct the disposition: 3,208,457

B. Oracle Partners, L.P.

(a) Amount beneficially owned: 2,253,061

(b) Percent of class: 6.6%

(c) Number of shares as to which such person has:

(i)    Sole power to vote or direct the vote: 0

(ii)   Shared power to vote or direct the vote: 2,253,061

(iii)  Sole power to dispose or direct the disposition: 0

(iv)  Shared power to dispose or direct the disposition: 2,253,061

C. Oracle Institutional Partners, L.P.

(a) Amount beneficially owned: 308,100

(b) Percent of class: 0.9%

(c) Number of shares as to which such person has:

(i)   Sole power to vote or direct the vote: 0

(ii)  Shared power to vote or direct the vote: 308,100

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 308,100

D. Oracle Associates, LLC

(a) Amount beneficially owned: 2,561,161

(b) Percent of class: 7.5%

(c) Number of shares as to which such person has:

(i)   Sole power to vote or direct the vote: 0

(ii)  Shared power to vote or direct the vote: 2,561,161

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 2,561,161

E. Oracle Ten Fund Master, L.P.

(a) Amount beneficially owned: 598,796

(b) Percent of class: 1.8%

(c) Number of shares as to which such person has:

(i)   Sole power to vote or direct the vote: 0

(ii)  Shared power to vote or direct the vote: 598,796

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 598,796

F. Oracle Investment Management, Inc. Employees’ Retirement Plan

(a) Amount beneficially owned: 42,000

(b) Percent of class: 0.1%

(c) Number of shares as to which such person has:

(i)   Sole power to vote or direct the vote: 0

(ii)  Shared power to vote or direct the vote: 42,000

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 42,000

G. Oracle Investment Management, Inc.

(a) Amount beneficially owned: 640,796

(b) Percent of class: 1.9%

(c) Number of shares as to which such person has:

(i)   Sole power to vote or direct the vote: 0

(ii)  Shared power to vote or direct the vote: 640,796

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 640,796

H. The Feinberg Family Foundation

(a) Amount beneficially owned: 6,500

(b) Percent of class: 0.0%

(c) Number of shares as to which such person has:

(i)   Sole power to vote or direct the vote: 0

(ii)  Shared power to vote or direct the vote: 6,500

(iii) Sole power to dispose or direct the disposition: 0

(iv) Shared power to dispose or direct the disposition: 6,500

Item 10:  Certification:

Each of the Reporting Persons hereby makes the following certification:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated:       February 13, 2014