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EXHIBIT 5.1
[LATHAM & WATKINS LETTERHEAD]
December 18, 2000
Aviron
297 North Bernardo Avenue
Mountain View, CA 94043
Re: $400,000,000 Aggregate Offering Price of Securities of Aviron
Ladies and Gentlemen:
In connection with the registration statement on Form S-3 (the
"Registration Statement") filed on December 18, 2000 with the Securities and
Exchange Commission under the Securities Act of 1933, as amended (the
"Securities Act"), you have requested our opinion with respect to the matters
set forth below.
You have provided us with a draft prospectus (the "Prospectus") which is a
part of the Registration Statement. The Prospectus provides that it will be
supplemented in the future by one or more supplements to the Prospectus (each a
"Prospectus Supplement"). The Prospectus as supplemented by various Prospectus
Supplements will provide for the registration by Aviron, a Delaware corporation
(the "Company"), of up to $400,000,000 aggregate offering price of (i) one or
more series of senior, senior subordinated or subordinated debt securities (the
"Debt Securities") or (ii) shares of common stock, par value $0.001 per share
(the "Common Stock"). The Debt Securities and Common Stock are collectively
referred to herein as the "Securities." Any Debt Securities may be exchangeable
and/or convertible into shares of Common Stock. The Debt Securities may be
issued pursuant to the subordinated indenture, the form of which is attached as
Exhibit 4.26 to the Registration Statement (the "Subordinated Indenture"), or
the senior indenture, the form of which is attached as Exhibit 4.25 to the
Registration Statement (the "Senior Indenture," and, together with the
Subordinated Indenture, each an "Indenture" and collectively, the "Indentures"),
in each case between the Company and a trustee (the "Trustee").
In our capacity as your special counsel in connection with the Registration
Statement, we are familiar with the proceedings taken and proposed to be taken
by the Company in connection with the authorization and issuance of the
Securities, and for the purposes of this opinion, have assumed that such
proceedings will be timely completed in the manner presently proposed. In
addition, we have made such legal and factual examinations and inquiries,
including an examination of originals and copies certified or otherwise
identified to our satisfaction of such documents, corporate records and
instruments, as we have deemed necessary or appropriate for purposes of this
opinion.
In our examination, we have assumed the genuineness of all signatures, the
authenticity of all documents submitted to us as originals, and the conformity
to authentic original documents of all documents submitted to us as copies.
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We have been furnished with, and with your consent have exclusively relied
upon, certificates of officers of the Company with respect to certain factual
matters. In addition, we have obtained and relied upon such certificates and
assurances from public officials as we have deemed necessary.
For purposes of this opinion, we have assumed that proper proceedings in
connection with the authorization and issuance of the Securities will be timely
and properly completed, in accordance with all requirements of applicable
federal and New York laws and the General Corporation Law of the State of
Delaware (the "Delaware GCL") in the manner presently proposed.
We are opining herein as to the effect on the subject transaction only of
the federal securities laws of the United States, the Delaware GCL, and with
respect to the opinions set forth in paragraphs 1 and 3 below, the internal laws
of the State of New York, and we express no opinion with respect to the
applicability thereto, or the effect thereon, of the laws of any other
jurisdiction or, in the case of Delaware, any other laws, or as to any matters
of municipal law or the laws of any local agencies within any state.
Subject to the foregoing and the other matters set forth herein, it is our
opinion that as of the date hereof:
1. When (i) the Debt Securities have been duly established in accordance
with the applicable Indenture (including, without limitation, the adoption by
the Board of Directors of the Company of a resolution duly authorizing the
issuance and delivery of the Debt Securities), duly authenticated by the Trustee
and duly executed and delivered on behalf of the Company against payment
therefor in accordance with the terms and provisions of the applicable Indenture
and as contemplated by the Registration Statement, the Prospectus and the
related Prospectus Supplement(s), and (ii) when the Registration Statement and
any required post-effective amendment thereto and any and all Prospectus
Supplement(s) required by applicable laws have all become effective under the
Securities Act, and (iii) assuming that the terms of the Debt Securities as
executed and delivered are as described in the Registration Statement, the
Prospectus and the related Prospectus Supplement(s), and (iv) assuming that the
Debt Securities as executed and delivered do not violate any law applicable to
the Company or result in a default under or breach of any agreement or
instrument binding upon the Company, and (v) assuming that the Debt Securities
as executed and delivered comply with all requirements and restrictions, if any,
applicable to the Company, whether imposed by any court or governmental or
regulatory body having jurisdiction over the Company, and (vi) assuming that the
Debt Securities are then issued and sold as contemplated in the Registration
Statement, the Prospectus and the related Prospectus Supplement(s), the Debt
Securities will constitute legal, valid and binding obligations of the Company,
enforceable against the Company in accordance with the terms of the Debt
Securities.
2. Assuming that (i) the terms of such shares as executed and delivered
are as described in the Registration Statement, the Prospectus and the related
Prospectus Supplement(s), (ii) the Company has a sufficient number of
authorized but unissued shares under the Company's Amended and Restated
Certificate of Incorporation, as amended, at the time of issuance, (iii) such
shares as executed and delivered do not violate any law applicable to the
Company or result in a default under or breach of any agreement or instrument
binding upon the Company, (iv) such shares as executed and delivered comply with
all requirements and restrictions, if any, applicable to the Company, whether
imposed by any court or governmental or regulatory body having jurisdiction over
the Company and (v) such shares are then issued and sold as contemplated in the
Registration Statement, such shares of Common Stock (including, without
limitation, any Common Stock duly issued upon the exchange or conversion of any
shares of preferred stock of the Company that are exchangeable or convertible
into Common Stock, upon the exercise of any warrants of the Company exercisable
for Common Stock or upon the exchange or conversion of Debt Securities that are
exchangeable or convertible into Common Stock) will be validly issued, fully
paid and nonassessable.
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3. When (i) the Registration Statement and any required post-effective
amendment thereto and any and all Prospectus Supplement(s) required by
applicable laws have all become effective under the Securities Act, and (ii)
when the Debt Securities have been duly executed and delivered by all parties
thereto, and (iii) assuming that the applicable Indenture does not violate any
law applicable to the Company or result in a default under or breach of any
agreement or instrument binding upon the Company, and (iv) assuming that the
applicable Indenture complies with all requirements and restrictions, if any,
applicable to the Company, whether imposed by any court or governmental or
regulatory body having jurisdiction over the Company, and (v) assuming that the
Debt Securities are then issued and sold as contemplated in the Registration
Statement, the Prospectus and the related Prospectus Supplement(s), the
applicable Indenture will constitute the legal, valid and binding obligation of
the Company, enforceable against the Company in accordance with the terms of
such Indenture.
The opinions set forth in paragraphs 1 and 3 above are subject to the
following exceptions, limitations and qualifications: (i) the effect of
bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium or
other similar laws now or hereafter in effect relating to or affecting the
rights or remedies of creditors; (ii) the effect of general principles of
equity, regardless of whether enforcement is considered in a proceeding in
equity or at law, and the discretion of the court before which any proceeding
therefor may be brought; (iii) the unenforceability under certain circumstances
under law or court decisions of provisions providing for the indemnification of,
or contribution to, a party with respect to a liability where such
indemnification or contribution is contrary to public policy; (iv) the
enforceability of any waiver of rights or defenses with respect to stay,
extension or usury laws; and (v) whether acceleration of Debt Securities may
affect the collectibility of any portion of the stated principal amount thereof
which might be determined to constitute unearned interest thereon.
We have not been requested to express and, with your knowledge and consent,
do not render any opinion as to the applicability to the obligations of the
Company under the Indentures and the Debt Securities of Section 548 of the
United States Bankruptcy Code or applicable state law (including, without
limitation, Article 10 of the New York Debtor and Creditor Law) relating to
fraudulent transfers and obligations.
We assume for purposes of this opinion that the Company has been duly
organized and is validly existing as a corporation under the laws of the State
of Delaware and has the corporate power and authority to issue and sell the
Securities; that the applicable Indenture has been duly authorized by all
necessary corporate action by the Company; that the Trustee for the applicable
Indenture is duly organized, validly existing and in good standing under the
laws of its jurisdiction of organization; that the Trustee is duly qualified to
engage in the activities contemplated by the applicable Indenture; that the
applicable Indenture has been duly authorized, executed and delivered by the
Trustee and constitutes a legal, valid and binding obligation of the Trustee,
enforceable against the Trustee in accordance with its terms; that the Trustee
is in compliance, generally and with respect to acting as Trustee under the
applicable Indenture, with all applicable laws and regulations; and that the
Trustee has the requisite organizational and legal power and authority to
perform its obligations under the applicable Indenture.
We consent to your filing this opinion as an exhibit to the Registration
Statement and to the reference to our firm under the caption "Legal Matters" in
the Prospectus included therein.
This opinion is rendered only to you and is solely for your benefit in
connection with the transactions covered hereby. This opinion may not be relied
upon by you for any other purpose, or furnished to, quoted to or relied upon by
any other person, firm or corporation for any purpose, without our prior written
consent.
Very truly yours,
/s/ Latham & Watkins
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