[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 trusts on how to vote their shares.

December 22, 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 VOTE PROMPTLY IN ONE OF THE FOLLOWING WAYS:

   1.  ONLINE
       Vote online at the web site address listed on your proxy card.

   2.  PHONE
       Call the toll-free number printed on your proxy card.

   3.  MAIL
       Complete and sign the enclosed proxy card and return by mail in the
       enclosed prepaid return envelope (if mailed in the United States).

   4.  IF YOU NEED ADDITIONAL ASSISTANCE A REPRESENTATIVE IS AVAILABLE.
       PLEASE CALL 1-877-288-6170 AS SOON AS POSSIBLE AND HAVE THE ENCLOSED
       PROXY CARE IN HAND TO PROVIDE OUR REPRESENTATIVE WITH THE INFORMATION
       REQUIRED TO CAST YOU 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


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,
333-119448, 333-119449, 333-119450, 333-119451, 333-119452, 333-119453,
333-119454, 333-119456, 333-119458, 333-119459, 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.