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PROSPECTUS SUPPLEMENT NO. 4 DATED
DECEMBER 7, 1999 Rule 424(b) (3)
Registration Statement No. 333-00667
QUIDEL CORPORATION
2,366,665 SHARES OF COMMON STOCK
This Prospectus Supplement supplements, and must be received in conjunction
with, the information contained in the Quidel Corporation ("Company")
Prospectus previously filed with the Securities and Exchange Commission and
declared effective on February 13, 1996, as supplemented by Prospectus
Supplement No. 1 previously filed with the Commission on February 16, 1996,
Prospectus Supplement No. 2 filed on March 18, 1996, and Prospectus
Supplement No. 3 filed on October 3, 1996. The information contained in the
Selling Security Holder table and footnotes set forth below modifies and
supersedes in its entirety the information contained in the Selling Security
Holder table and footnotes thereto set forth on pages 9 and 10 of the
Prospectus. This Prospectus Supplement must be delivered with a copy of the
Prospectus.
SELLING SECURITY HOLDERS
The following table sets forth certain information regarding the beneficial
ownership of the Company's Common Stock by the Selling Security Holders as of
December 6, 1999, as adjusted to reflect the assignment of the warrant
originally issued to Genesis Merchant Group Securities. See "Shares Covered."
<TABLE>
<CAPTION>
Maximum
Number of
Shares Beneficially Shares Shares Beneficially
Owned Covered by Owned
Prior to Offering (1) this Prospectus (2) After Offering
-------------------------- --------------------- ----------------------------
Name Number Percent (3) Number Percent (3)(4)
- ---------------------------------- ---------- ------------- --------- ----------------
<S> <C> <C> <C> <C> <C>
Erik Colberg (5) 10,000 * 10,000 0 *
D. E. Shaw Investments L.P. 350,000 1.6% 350,000 0 *
Diversified Financial 27,900 * 27,900 0 *
Management Corporation (5)
Grange Trustees Limited, 12,500 * 12,500 0 *
Trustees of
The Chester Trust
Imperial Bank 117,871 * 117,871 0 *
JB Capital Management, 6,822 * 6,822 0 *
Inc. (5)
- -------------------------------------------------------------------------------------------------------------------------
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JMG Convertible Investments L.P. 100,000 * 100,000 0 *
J. P. Morgan Investment 2,015,254 8.9% 1,015,254 1,000,000 4.2%
Corporation
Peter J. Monti (5) 5,000 * 5,000 0 *
Pomona Capital LP 2 56,403 * 56,403 0 *
Portola Capital 50,000 * 50,000 0 *
Management, Inc.
Redington, Inc. (6) 50,000 * 50,000 0 *
Reliant Trading 150,000 * 150,000 0 *
Barry S. Rosenstein Corp. (7) 57,126 * 57,126 0 *
Barry S. Rosenstein Corp. 45,000 * 45,000 0 *
Defined Contribution Plan and
Trust
Gail Seneca (5) 10,595 * 10,595 0 *
SOF Venture Capital, LP 49,291 * 49,291 0 *
SP Offshore Venture Capital 38,462 * 38,462 0 *
Patricia Stapleton (5) 11,470 * 11,470 0 *
Philip C. Stapleton (5) 11,471 * 11,471 0 *
Steinhardt Partners, LP 25,051 * 25,051 0 *
SZRL (5) 13,029 * 13,029 0 *
Will K. Weinstein Rev. Trust UA 64,560 * 64,560 0 *
DTD 2/27/90 (5)
T.E. James, Inc. (5) 12,027 * 12,027 0 *
TQA Leverage Fund, L.P. 76,833 * 76,833 0 *
</TABLE>
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* Less than one percent.
(1) Represents sole voting and investment power unless otherwise indicated.
(2) All shares covered by this Prospectus are shares of the Company's Common
Stock to be obtained by the Selling Security Holders upon exercise of their
respective outstanding warrants.
(3) The percentage ownership for each Selling Security Holder is calculated by
assuming the exercise or conversion of all outstanding and vested warrants,
rights and convertible securities.
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(4) The percentage ownership of shares beneficially owned by each Selling
Security Holder after the offering is calculated by assuming the sale by
each Selling Security Holder of all such Selling Security Holder's shares
of the Company's common Stock covered by this Prospectus.
(5) Shares received by assignment of the warrant to purchase 173,250 shares
originally issued to Genesis Merchant Group Securities.
(6) These shares are shares of the Company's Common Stock to be obtained upon
exercise of outstanding warrants, currently comprised of 25,000 vested
warrants and an additional 25,000 warrants whose vesting in increments of
12,500 shares each is conditioned upon the Company's Common Stock trading
at or above certain market prices for certain periods of time.
(7) Includes 376 shares assigned from Genesis Merchant Group Securities.
The date of this Prospectus Supplement No. 4 is December 7, 1999.
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