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EXHIBIT 5.1
HALE AND DORR LLP
60 STATE STREET
BOSTON, MASSACHUSETTS 02109
August 1, 2000
Millennium Pharmaceuticals, Inc.
75 Sidney Street
Cambridge, MA 02139
Ladies and Gentlemen:
This opinion is furnished to you in connection with the Registration
Statement on Form S-4 (the "Registration Statement") being filed by
Millennium Pharmaceuticals, Inc., a Delaware corporation (the "Company"),
with the Securities and Exchange Commission (the "Commission") under the
Securities Act of 1933, as amended (the "Securities Act"), with respect to
5,120,000 shares (the "Shares") of the Company's common stock, $0.001 par
value per share (the "Common Stock"), all of which may be issued from time to
time on a delayed or continuous basis pursuant to Rule 415 under the
Securities Act.
We have examined the Registration Statement, including the exhibits
thereto, and such other documents, corporate records and instruments and have
examined such laws and regulations as we have deemed necessary for purposes
of rendering the opinions set forth herein. Based upon such examination, we
are of the opinion that the Shares, when (i) specifically authorized for
issuance by the Company's Board of Directors or an authorized committee
thereof (the "Authorizing Votes"), (ii) the Registration Statement has become
effective under the Securities Act, (iii) the terms of the sale of the Shares
have been duly established in conformity with the Company's Certificate of
Incorporation and By-laws and do not violate any applicable law or result in
a default under or breach of any agreement or instrument binding on the
Company and comply with any requirement or restriction imposed by any court
or governmental body having jurisdiction over the Company, (iv) the Shares
have been issued and sold as contemplated by the Registration Statement, and
(v) the Company has received the consideration provided for in the
Authorizing Votes, will be validly issued, fully paid and nonassessable.
We express no opinion with respect to the applicability of any law
other than the state laws of the Commonwealth of Massachusetts, the Delaware
General Corporation Law and United States Federal laws. To the extent that
any applicable document is stated to be governed by the laws of another
jurisdiction, we have assumed for purposes of this opinion that the laws of
such jurisdiction are identical to the state laws of the Commonwealth of
Massachusetts.
It is understood that this opinion is to be used only in connection
with the offer and sale of the Shares while the Registration Statement is in
effect.
Please note that we are opining only as to the matters expressly set
forth herein, and no opinion should be inferred as to any other matters. This
opinion is based upon currently existing statutes, rules, regulations and
judicial decisions, and we disclaim any obligation to advise you of any change
in any of these sources of law or subsequent legal or factual developments which
might affect any matters or opinions set forth herein.
We hereby consent to the filing of this opinion with the Commission as
an exhibit to the Registration Statement in accordance with the requirements of
Item 601(b) (5) of Regulation S-K under the Securities Act and to the use of
this Firm's name therein and in the related Prospectus under the caption
"Validity of Securities." In giving such consent, we do not hereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Securities Act or the rules and regulations of the Commission.
Very truly yours,
/s/ HALE AND DORR LLP
