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[ROPES & GRAY LETTER HEAD]

                                                               November 20, 2002


State Street Research Securities
  Trust, on behalf of its Legacy
  Fund series
One Financial Center
Boston, MA  02111

Ladies and Gentlemen:

     You have requested our opinion in connection with the acquisition as
contemplated by the Agreement and Plan of Reorganization, dated as of
October 7, 2002 (the "AGREEMENT"), by and between State Street Research
Growth Trust, a Massachusetts business trust, on behalf of its State Street
Research Large-Cap Growth Fund series (the "ACQUIRED FUND"), and the State
Street Research Securities Trust, a Massachusetts business trust (the
"SECURITIES TRUST"), on behalf of its Legacy Fund series (the "ACQUIRING
FUND") (the "REORGANIZATION"). Capitalized terms used herein but not defined
shall have the meanings ascribed to them in the Agreement.

     In connection with this opinion, we have examined the executed copies of
the Agreement; copies of the resolutions adopted at the meetings of the Trustees
of the Securities Trust held on October 7, 2002, as certified by the Assistant
Secretary of the Securities Trust; the Master Trust Agreement of the Securities
Trust, as amended, on file in the offices of the Secretary of The Commonwealth
of Massachusetts and the Clerk of the City of Boston (the "DECLARATION OF
TRUST") and as certified by the Assistant Secretary of the Securities Trust; a
copy of the By-laws of the Securities Trust, as amended, as certified by the
Assistant Secretary of the Securities Trust; and such other documents,
certificates and records as we have deemed necessary for the purpose of this
opinion.

     We have assumed the genuineness of the signatures on all documents examined
by us, the authenticity of all documents submitted to us as originals, and the
conformity to their corresponding originals of all documents submitted to us as
copies. We have also assumed that each of (i) the Prospectus; (ii) the
Registration Statement of the Securities Trust on Form N-14 as

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filed with the Securities Exchange Commission ("SEC") on November 20, 2002 (the
"REGISTRATION STATEMENT"); and (iii) the joint proxy statement of the Acquired
Fund and the Acquiring Fund, relating to the meeting of the Trusts' shareholders
to be held on February 21, 2003 to consider the Reorganization (the
"PROSPECTUS/PROXY STATEMENT"), complies and complied at all relevant times with
the Securities Act of 1933, as amended (the "1933 ACT"), the Securities Exchange
Act of 1934, as amended (the "1934 ACT"), and the Investment Company Act of
1940, as amended (the "1940 ACT").

     We express no opinion as to the laws of any jurisdiction other than The
Commonwealth of Massachusetts and the United States of America. Further, we
express no opinion as to the state securities or blue sky laws of any
jurisdiction, including The Commonwealth of Massachusetts.

     Based upon and subject to the foregoing, we are of the opinion that:

     1. The Securities Trust is a duly formed and validly existing
unincorporated voluntary association with transferable shares existing under and
by virtue of the laws of The Commonwealth of Massachusetts and has the power to
own all of its properties and to carry on its business as presently conducted.

     2. The Reorganization Shares are duly authorized and upon delivery to the
Acquired Fund as provided for by the Agreement will be validly issued, fully
paid and nonassessable by the Securities Trust and the Acquiring Fund and no
shareholder of the Acquiring Fund has any preemptive right to subscription or
purchase in respect thereof.

     The Securities Trust is an entity of the type commonly known as a
"Massachusetts business trust." Under Massachusetts law, shareholders of the
Securities Trust could, under certain circumstances, be held personally liable
for the obligations of the Securities Trust. However, the Declaration of Trust
disclaims shareholder liability for acts or obligations of the Securities Trust
and requires that the notice of such disclaimer be given in each agreement,
obligation or instrument entered into or executed by the Securities Trust. The
Declaration of Trust provides for indemnification out of the property of the
Acquiring Fund for all loss and expense of any shareholder held personally
liable for the obligations of the Securities Trust solely by reason of being or
having been a shareholder of the Acquiring Fund. Thus, the risk of a shareholder
incurring financial loss on account of shareholder liability is limited to
circumstances in which the Acquiring Fund itself would be unable to meet its
obligations.

     We hereby consent to the filing of a copy of this opinion with the SEC as
an exhibit to the Registration Statement.

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     This opinion is furnished by us solely for your benefit and, except as
expressly consented to by us in writing, may not be relied upon by any other
entity or individual.

                                  Very truly yours,

                                  /s/ Ropes & Gray
                                  Ropes & Gray