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EXHIBIT 5.1
[LETTERHEAD OF HELLER EHRMAN WHITE & McAULIFFE LLP]
December 28, 2000
Main (650) 324-7000
Fax (650) 324-0638
18103-1000
Thoratec Laboratories Corporation
6035 Stoneridge Drive
Pleasanton, California 94588
Registration Statement on Form S-4
Ladies and Gentlemen:
We have acted as counsel to Thoratec Laboratories Corporation, a
California corporation (the "Company"), in connection with the Registration
Statement on Form S-4 that the Company filed with the Securities and Exchange
Commission on November 1, 2000 (as later amended, the "Registration Statement"),
for the purpose of registering under the Securities Act of 1933, as amended,
33,109,880 shares of its common stock, no par value (the "Shares"). The Shares
will be exchanged for shares of Thermo Cardiosystems Inc. ("Cardiosystems") in
the merger of Lightning Acquisition Corp., a wholly-owned subsidiary of the
Company, into Cardiosystems under the Agreement and Plan of Merger dated as of
October 3, 2000 among the Company, Lightning Acquisition Corp., Cardiosystems
and Thermo Electron Corporation (the "Merger Agreement").
In rendering our opinion, we have examined such records, documents and
instruments as we deemed appropriate. We have assumed the authenticity of all
records, documents and instruments submitted to us as originals, the genuineness
of all signatures, the legal capacity of natural persons and the conformity to
the originals of all records, documents and instruments submitted to us as
copies.
This opinion is limited to the federal law of the United States of
America and the California Corporations Code. We disclaim any opinion as to the
laws of any other jurisdiction. We further disclaim any opinion as to any other
statute, rule, regulation, ordinance, order or other promulgation of any other
jurisdiction or any regional or local governmental body or as to any related
judicial or administrative opinion.
Based upon the foregoing and our examination of such questions of law
as we deemed necessary or appropriate for purposes of this opinion, and assuming
that: (i) the Registration Statement becomes and remains effective during the
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Thoratec Laboratories Corporation
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period when the Shares are offered and sold, (ii) the Shares are issued in
accordance with the Merger Agreement, (iii) appropriate certificates evidencing
the Shares are executed and delivered by the Company and (iv) all applicable
securities laws are complied with, it is our opinion that the Shares have been
legally authorized for issuance and, when issued to Cardiosystems' stockholders
in the manner provided in the Merger Agreement, will be legally issued, fully
paid and nonassessable.
This opinion is rendered to you in connection with the Registration
Statement and is solely for your benefit. This opinion may not be relied upon by
you for any other purpose, or relied upon by any other person or entity for any
purpose, without our prior written consent. We disclaim any obligation to advise
you of any change of law that occurs, or any facts of which we may become aware,
after the date of this opinion.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement.
Very truly yours,
/s/ Heller Ehrman White & McAuliffe LLP
