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EXHIBIT 5.1
November 14, 2000
SONUS Pharmaceuticals, Inc.
22026 20th Avenue, S.E.
Bothell, Washington 98021
Re: Registration Statement on Form S-8
Gentlemen:
At your request, we have examined the form of Registration
Statement on Form S-8 (the "Registration Statement") being filed by SONUS
Pharmaceuticals, Inc., a Delaware corporation (the "Company"), with the
Securities and Exchange Commission in connection with the registration under the
Securities Act of 1933, as amended, of an additional 800,000 shares of the
Company's common stock, $.001 par value ("Common Stock"), issuable under the
Company's 1999 Nonqualified Stock Incentive Plan and 2000 Stock Incentive Plan
(the "Plans").
We have examined the proceedings heretofore taken and are
familiar with the additional proceedings proposed to be taken by the Company in
connection with the authorization, issuance and sale of the securities referred
to above.
Based on the foregoing, it is our opinion that the 800,000
shares of Common Stock to be issued under the Plans against full payment in
accordance with the respective terms and conditions of the Plans will be legally
and validly issued, fully paid and nonassessable.
We consent to the use of this opinion as an exhibit to the
Registration Statement.
Very truly yours,
/s/ STRADLING, YOCCA, CARLSON & RAUTH
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STRADLING, YOCCA, CARLSON & RAUTH
