FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * PULIDO MARK   2. Issuer Name and Ticker or Trading Symbol QUIDEL CORP /DE/ [QDEL] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) P.O. BOX 1334 3. Date of Earliest Transaction (Month/Day/Year) 10/05/2011 (Street) RANCHO SANTA FE, CA 92067 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock (1) 10/05/2011   M   8,600 A $ 5.08 23,530 D   Common Stock (1) 10/05/2011   S   8,600 D $ 17.0176 (2) 14,930 D   Common Stock (1) 10/06/2011   M   17,000 A $ 5.08 31,930 D   Common Stock (1) 10/06/2011   S   17,000 D $ 17.0266 (3) 14,930 D   Common Stock (1) 10/07/2011   M   10,670 A $ 5.08 25,600 D   Common Stock (1) 10/07/2011   S   10,670 D $ 17.0407 (4) 14,930 D

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Non-Qualified Stock Options

$ 5.08

10/05/2011

M

8,600

08/21/2003

08/21/2012

Common Stock

8,600

$ 0

31,400

D

Non-Qualified Stock Options

$ 5.08

10/06/2011

M

17,000

08/21/2006

08/21/2012

Common Stock

17,000

$ 0

14,400

D

Non-Qualified Stock Options

$ 5.08

10/07/2011

M

10,670

08/21/2006

08/21/2012

Common Stock

10,670

$ 0

3,730

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
PULIDO MARK P.O. BOX 1334 RANCHO SANTA FE, CA 92067	X

Signatures

Robert J. Bujarski, attorney-in-fact for Mark Pulido		10/07/2011
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	All of the transactions reported in this Form 4 were effected pursuant to a pre-established Rule 10b5-1 trading plan.
(2)	The weighted average purchase price for these transactions was $17.0176 per share, with a range of $17.00 to $17.11 per share. 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 purchased at each separate price.
(3)	The weighted average purchase price for these transactions was $17.0266 per share, with a range of $17.00 to $17.15 per share. 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 purchased at each separate price.
(4)	The weighted average purchase price for these transactions was $17.0407 per share, with a range of $17.00 to $17.1243 per share. 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 purchased at each separate price.

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