<PAGE>
As filed with the Securities and Exchange Commission on May 22, 1997
Registration No. 33-55990
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U.S. SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
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POST-EFFECTIVE AMENDMENT NO. 1
TO
FORM S-3
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
SYNBIOTICS CORPORATION
(Name of registrant as specified in its charter)
CALIFORNIA 95-3737816
(State or other jurisdiction of (I.R.S. Employer
incorporation or organization) Identification No.)
11011 VIA FRONTERA
SAN DIEGO, CALIFORNIA 92127
(Address of principal executive offices) (Zip Code)
KENNETH M. COHEN
PRESIDENT AND CHIEF EXECUTIVE OFFICER
SYNBIOTICS CORPORATION
11011 VIA FRONTERA, SAN DIEGO, CALIFORNIA 92127
(Name and address of agent for service)
(619) 451-3771
(Telephone number, including area code, of agent for service)
Copies to:
HAYDEN J. TRUBITT, ESQ.
BROBECK, PHLEGER & HARRISON
550 West C Street, Suite 1300
San Diego, California 92101
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Approximate date of commencement of proposed sale to the public
From time to time after the effective date of this Registration Statement
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If the only securities being registered on this Form are being offered pursuant
to dividend or interest reinvestment plans, please check the following box:
[_]
If any of the securities being registered on this Form are to be offered on a
delayed or continuous basis pursuant to Rule 415 under the Securities Act of
1933, other than securities offered only in connection with dividend or interest
reinvestment plans, check the following box: [X]
If this Form is filed to register additional securities for an offering pursuant
to Rule 462(b) under the Securities Act, please check the following box and list
the Securities Act registration statement number of the earlier effective
registration statement for the same offering: [_]
If this Form is a post-effective amendment filed pursuant to Rule 462(c) under
the Securities Act, check the following box and list the Securities Act
registration statement number of the earlier effective registration statement
for the same offering: [_]
If delivery of the prospectus is expected to be made pursuant to Rule 434,
please check the following box: [_]
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SYNBIOTICS CORPORATION
Deregistration
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This Registration Statement, as amended to the date of its effectiveness (May
10, 1993), registered 458,806 shares of the Common Stock of Synbiotics
Corporation (the "Company"). These shares (the "Shares") were offered for
resale by a company now known as Mallinckrodt Inc. ("Mallinckrodt"), who
received such Shares in connection with a 1987 research and development
agreement and a 1992 sale of product rights. Mallinckrodt sold, under rule
144(k), 55,900 of the Shares in 1997. Mallinckrodt and the Company have agreed
to deregister all the unsold Shares at this time. Mallinckrodt may continue to
sell such Shares as may be permitted by Rule 144(k). Accordingly, the Company
hereby deregisters 402,906 shares of the Common Stock originally covered by the
Registration Statement.
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SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, the Company has duly
caused this Registration Statement to be signed on its behalf by the
undersigned, thereunto duly authorized, in the City of San Diego, State of
California, on this 22nd day of May, 1997.
SYNBIOTICS CORPORATION
By /s/ KENNETH M. COHEN
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Kenneth M. Cohen
President and Chief Executive Officer
<TABLE>
<CAPTION>
SIGNATURE TITLE DATE
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<S> <C> <C>
/s/ KENNETH M. COHEN Chief Executive Officer, President and Director May 22, 1997
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Kenneth M. Cohen (Principal Executive Officer)
/s/ MICHAEL K. GREEN Chief Financial Officer Vice President - Finance May 22, 1997
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Michael K. Green (Principal Financial Officer)
/s/ KEITH A. BUTLER Chief Accounting Officer and Corporate Controller May 22, 1997
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Keith A. Butler (Principal Accounting Officer)
* Director May 22, 1997
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Patrick Owen Burns
/s/ JAMES C. DECESARE Director May 22, 1997
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James C. DeCesare
/s/ BRENDA D. GAVIN Director May 22, 1997
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Brenda D. Gavin
/s/ M. BLAKE INGLE Director May 22, 1997
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M. Blake Ingle
* Director May 22, 1997
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Donald E. Phillips
*/s/ MICHAEL K. GREEN May 22, 1997
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(Michael K. Green, Attorney-in-Fact)
</TABLE>
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