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VENTURE LAW GROUP
A Professional Corporation
4750 Carillon Point
Kirkland, WA 98033
(425) 739-8700 phone
(425) 739-8750 facsimile
August 3, 2000
Rosetta Inpharmatics, Inc.
12040-115th Ave, NE
Kirkland,WA 98034
Registration Statement on Form S-1
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Ladies and Gentlemen:
We have examined the Registration Statement on Form S-1 (the
"Registration Statement") to be filed by you, Rosetta Inpharmatics, Inc., with
the Securities and Exchange Commission in connection with the registration under
the Securities Act of 1933, as amended, of 230,000 shares of your Common Stock
(the "Shares"). The Shares include an over-allotment option to purchase 30,000
shares granted by the Company to the underwriters. As your counsel in connection
with this transaction, we have examined the proceedings taken and are familiar
with the proceedings proposed to be taken by you in connection with the sale and
issuance of the Shares.
It is our opinion that upon conclusion of the proceedings being taken
or contemplated by us, as your counsel, to be taken prior to the issuance of the
Shares, and upon completion of the proceedings being taken in order to permit
such transactions to be carried out in accordance with the securities laws of
the various states where required, the Shares, when issued and sold in the
manner described in the Registration Statement, will be legally and validly
issued, fully paid and non-assessable.
We consent to the use of this opinion as an exhibit to the Registration
Statement, and further consent to the use of our name wherever appearing in the
Registration Statement, including the Prospectus constituting a part thereof,
and in any amendment thereto.
Very truly yours,
/s/ VENTURE LAW GROUP
