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Exhibit 5.1
BINGHAM DANA LLP
150 Federal Street
Boston, MA 02110
January 11, 2001
Sonus Networks, Inc.
5 Carlisle Ave.
Westford, MA 01886
Re: Registration Statement on Form S-4 (file no. 333-52682) under
the Securities Act of 1933, as amended
Ladies and Gentlemen:
We have acted as counsel to Sonus Networks, Inc., a Delaware
corporation (the "Company"), in connection with the registration under the
Securities Act of 1933, as amended (the "Act"), of 15,000,000 shares (the
"Shares") of the Company's Common Stock, $0.001 par value per share, pursuant to
a Registration Statement on Form S-4 initially filed by the Company with the
Securities and Exchange Commission on December 22, 2000.
The Shares are to be issued in exchange for shares of telecom
technologies, inc. ("TTI") common stock pursuant to the Agreement and Plan of
Merger and Reorganization, dated as of November 2, 2000, by and among the
Company, TTI and Storm Merger Sub, Inc. (the "Merger Agreement").
As counsel to the Company, we have reviewed the corporate proceedings
taken by the Company with respect to the authorization of the issuance of the
Shares. We have also examined and relied upon originals or copies, certified or
otherwise authenticated to our satisfaction, of such corporate records,
documents, agreements or other instruments of the Company. As to all matters of
fact (including factual conclusions and characterizations and descriptions of
purpose, intention or other state of mind) we have entirely relied upon
certificates of officers of the Company, and have assumed, without independent
inquiry, the accuracy of those certificates.
We have assumed the genuineness of all signatures, the conformity to
the originals of all documents reviewed by us as copies, the authenticity and
completeness of all original documents reviewed by us in original or copy form
and the legal competence of each individual executing a document. We have also
assumed that the registration requirements of the Act and all applicable
requirements of state laws regulating the sale of securities will have been duly
satisfied. We have also assumed that the Company has received the specified
consideration for the Shares.
This opinion is limited solely to the Delaware General Corporation Law,
as applied by courts located in Delaware, the applicable provisions of the
Delaware Constitution and the reported judicial decisions interpreting those
laws.
Subject to the foregoing, it is our opinion that the Shares have been
duly authorized and, upon issuance of the Shares in accordance with the terms of
the Merger Agreement, will be validly issued, fully paid and non-assessable.
We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to this firm under the heading
"Legal Matters" in the Prospectus included in the Registration Statement.
Very truly yours,
/s/ Bingham Dana LLP
Bingham Dana LLP
