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[STATE STREET RESEARCH LOGO]

Filed by State Street Research Securities Trust
Pursuant to Rule 425 Under the Securities Act of 1933 and
Deemed filed pursuant to Rule 14a-2 of the
Securities Exchange Act of 1934
Subject Company: State Street Research Securities Trust
SEC File No. 33-74628

This filing relates to the proposed reorganizations of certain series of
State Street Research trusts ("State Street Research") into certain series of
the BlackRock Funds ("BlackRock") pursuant to Agreements and Plans of
Reorganization, forms of which are on file with the U.S. Securities and
Exchange Commission as appendices to the Combined Prospectus/Proxy Statements
on Form N-14 filed by BlackRock on November 8, 2004, and which are
incorporated by reference into this filing.

The following is a letter sent to certain shareholders of the series of the
trusts reminding them to instruct the Trust on how to vote their shares.

December 20, 2004


                                    REMINDER


Dear Shareholder,

In mid-November, we mailed you proxy materials requesting your vote on an
important proposal affecting your State Street Research fund(s). As of today,
we have not received instructions on how to vote your shares. If you have
already voted, we thank you for your consideration.

IF YOU HAVE NOT YET VOTED, PLEASE CALL 1-877-288-6170 AS SOON AS POSSIBLE AND
HAVE THE ENCLOSED BALLOT IN HAND TO PROVIDE OUR REPRESENTATIVE WITH THE
INFORMATION REQUIRED TO CAST YOUR VOTE.

As a shareholder, your vote is important. We hope that you will respond today
to ensure that your shares will be represented at the meeting.

If you have any questions about the proxy materials you received, please call
the number provided above or contact your financial advisor.


Sincerely,

/s/ Richard S. Davis

Richard S. Davis
Chairman of the Board
President & Chief Executive Officer

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[STATE STREET RESEARCH LOGO]

ADDITIONAL INFORMATION AND WHERE TO FIND IT

BlackRock Funds ("BlackRock") has filed Combined Prospectus / Proxy
Statements with the Securities and Exchange Commission Registration
Statements, on Form N-14 (Nos. 333-119445, 333-119446, 333-119447,
333-119457, 333-119448, 333-119449, 333-119450, 333-119451, 333-119452,
333-119453, 333-119454, 333-119456, 333-119458, 333-119459 and 333-119461),
of BlackRock and certain State Street Research ("SSR") funds and other
relevant materials regarding the proposed reorganizations (the
"Reorganizations") of certain series of SSR trusts into certain series of
BlackRock. The Combined Prospectus/Proxy Statements were sent to security
holders of SSR funds seeking their approval of the Reorganizations. WE URGE
YOU TO READ THE COMBINED PROSPECTUS/PROXY STATEMENTS FILED BY BLACKROCK WITH
THE SEC ON NOVEMBER 8, 2004 AND THE OTHER RELEVANT MATERIALS FILED BY
BLACKROCK OR SSR WITH THE SEC BEFORE VOTING OR MAKING ANY INVESTMENT DECISION
WITH RESPECT TO THE REORGANIZATIONS, BECAUSE THEY CONTAIN IMPORTANT
INFORMATION ABOUT BLACKROCK, SSR AND THE REORGANIZATIONS. You may obtain a
free copy of these materials and other documents filed by BlackRock or SSR
with the SEC at the SEC's website at www.sec.gov. In addition, the documents
filed with the SEC by BlackRock may be obtained free of charge by directing
such request to: BlackRock Funds, Bellevue Park Corporate Center, 100
Bellevue Parkway, Wilmington, Delaware, 19809, (800) 441-7762. Documents
filed with the SEC by SSR may be obtained free of charge by directing such
request to: State Street Research, One Financial Center, Boston,
Massachusetts, 02111, (877) 773-8637.