<Page>
Filed by State Street Research Capital Trust
Pursuant to Rule 425 under the Securities Act of 1933 and
deemed filed pursuant to Rule 14a-12 of the
Securities Exchange Act of 1934
Subject Company: State Street Research Capital Trust
SEC File No. 2-86271
[STATE STREET RESEARCH LOGO]
STATE STREET RESEARCH SHAREHOLDERS RECEIVE
PROSPECTUS/PROXY STATEMENT IN NOVEMBER MAILING
State Street Research (SSR) shareholders will be sent a prospectus/proxy
statement the week of November 8 soliciting their approval of the reorganization
of SSR funds into BlackRock funds in connection with BlackRock's recent
agreement to acquire the parent company of State Street Research & Management
Company (SSRM), the investment adviser to the SSR funds, from MetLife, Inc.
The questions and answers below provide you with an overview of the proxies and
should help you respond to inquiries from your clients. In addition, a grid is
included that outlines the proposed fund line-up and portfolio management teams.
We appreciate your patience and understanding during this period of transition
and thank you for your continued support. IF YOU NEED FURTHER INFORMATION,
PLEASE CALL US AT 1-800-882-0052, MENU OPTION 5, EXT. 1400.
PROSPECTUS/PROXY MAILING - QUESTIONS & ANSWERS
Q - WHEN IS THE SSR PROXY MAILING TAKING PLACE?
A - The proxy is expected to mail the week of November 8, 2004.
Q - WHEN IS THE BLACKROCK ACQUISITION OF THE SSR BUSINESS EXPECTED TO CLOSE?
A - The transaction is expected to close in early 2005.
Q - WHEN IS THE SSR SHAREHOLDER MEETING AND WHY IS IT BEING HELD?
A - The meeting is scheduled for December 27, 2004. SSR fund shareholders will
be asked to cast their vote for the proposed reorganization of SSR funds
into BlackRock funds. Shareholders may also choose to vote their proxies by
telephone, via the Internet or by mail. It is very important that voting
instructions be received NO LATER THAN DECEMBER 24, 2004.
Q - WHAT IS THE PURPOSE OF THIS PARTICULAR PROXY SOLICITATION?
A - After careful consideration, the Board of Trustees of the SSR funds has
determined that the proposed reorganizations will benefit the shareholders
of SSR funds and recommends that shareholders carefully consider and approve
the proposal.
Q - HOW WILL SHAREHOLDERS BENEFIT IF THE PROPOSAL IS APPROVED?
A - The Board of Trustees of the SSR funds believes that shareholders will
benefit from:
- similarities between the investment objectives and policies of each
BlackRock fund and the respective SSR fund;
- the fact that BlackRock has committed to maintain the combined fund's
net operating expense ratio at a level no greater than that of the SSR
fund until February 1, 2007;
- the combined fund family having access to significantly more
investment professionals and related resources; and
- the same level of services shareholders currently receive, in addition
to a broader array of options offered by a larger fund family.
Q - WHEN WILL THE REORGANIZATIONS OCCUR?
A - If approved by shareholders, the reorganizations are expected to occur in
early 2005, along with BlackRock's acquisition of SSRM Holdings, Inc. The
reorganizations will not take place in the event that for any reason
BlackRock does not acquire SSRM Holdings, Inc.
FOR USE WITH BROKER/DEALERS ONLY.
NO PORTION OF THIS PUBLICATION MAY BE SHOWN OR DISTRIBUTED TO THE PUBLIC OR USED
IN ORAL OR WRITTEN FORM IN SOLICITING SALES.
<Page>
STATE STREET RESEARCH SHAREHOLDERS RECEIVE
PROXY STATEMENT IN NOVEMBER MAILING (cont.)
Q - HOW WILL THE REORGANIZATION AFFECT SHAREHOLDERS?
A - If the proposed reorganization is approved, the assets and certain stated
liabilities of each SSR fund will be combined with those of the respective
BlackRock fund, accounts will be set up for shareholders at BlackRock and
they will receive shares of the BlackRock fund. Shareholders of the SSR fund
would receive shares of the BlackRock fund with an aggregate value
equivalent to the net asset value of their SSR fund shares at the time of
the transaction.
Q - WILL SHAREHOLDERS HAVE TO PAY ANY SALES LOAD, COMMISSION OR OTHER SIMILAR
FEE IN CONNECTION WITH THE REORGANIZATION?
A - Shareholders will pay no sales load, commission or other similar fee in
connection with the reorganization. As more fully discussed in the
prospectus/proxy statement, the holding period with respect to any
contingent deferred sales charges applicable to shares of the BlackRock fund
received by shareholders in the reorganization will relate back to their
original aquisition of shares of the SSR fund and as such will be measured
from the earlier of the time (i) they purchased the shares from the SSR fund
or (ii) they purchased their shares of any other SSR fund and subsequently
exchanged them for shares of the SSR fund.
Q - WILL SHAREHOLDERS HAVE TO PAY ANY FEDERAL TAXES AS A RESULT OF THE
REORGANIZATION?
A - The reorganization is expected to qualify as a "reorganization" within the
meaning of Section 368(a) of the Internal Revenue Code of 1986, as amended.
If the reorganization so qualifies, in general, a fund will not recognize
any gain or loss as a result of the transfer of all of its assets and
certain stated liabilities in exchange solely for the shares of the
BlackRock fund or as a result of its liquidation, and its shareholders will
not recognize any gain or loss upon their receipt solely of the shares of
the BlackRock fund in connection with the reorganization.
Q - WILL SSR PORTFOLIO MANAGERS CONTINUE TO MANAGE ALL MUTUAL FUNDS?
A - The Board of Trustees of the SSR funds believes that the combined fund
family will have access to significantly more investment professionals and
related resources. In some cases, the combined fund portfolio management
team is expected to be led by current SSR managers; in other cases, the team
is expected to be led by BlackRock managers; and in other cases, the team is
expected to be led by a merged group of SSR and BlackRock managers.
ADDITIONAL INFORMATION AND WHERE TO FIND IT
BlackRock Funds ("BlackRock") has filed Combined Prospectus/Proxy Statements
with the Securities and Exchange Commission (SEC)
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 funds. The Combined Prospectus/Proxy Statements, of which this
Questions and Answers summary is a part, is being sent, simultaneously with
the summary, to security holders of SSR 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 on 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.
FOR USE WITH BROKER/DEALERS ONLY.
NO PORTION OF THIS PUBLICATION MAY BE SHOWN OR DISTRIBUTED TO THE PUBLIC OR
USED IN ORAL OR WRITTEN FORM IN SOLICITING SALES.
<Page>
PROPOSED FUND LINE-UP AND PORTFOLIO MANAGEMENT TEAMS
<Table>
<Caption>
SSR FUND MERGE INTO INVESTMENT STYLE BENCHMARK FOR BLK FUND PM TEAM SURVIVING TRACK RECORD
SSR ASSET BLK Balanced Keep existing 60% S&P 500, Merged team led by Andrew SSR Asset Allocation
ALLOCATION strategy 40% Lehman US Damm (BLK) & Linda Zhang
Aggregate (SSR)
SSR AURORA BLK Aurora Keep active Russell 2500(R) Value Merged team led by Wayne SSR Aurora
fundamental Archambo (BLK)
SSR EMERGING BLK Emerging Keep active Russell 2500(R) Growth Consolidate under merged SSR Emerging
GROWTH Growth fundamental team led by Neil Wagner (BLK) Growth
& Eileen Leary (SSR)
SSR GLOBAL BLK Global Keep active Wilshire 5000 SSR energy team led by Dan SSR Global Resources
RESOURCES Resources fundamental Modified Energy Rice & Denis Walsh
SSR GOVERNMENT BLK Keep relative Lehman Intermediate BLK fixed income team BLK Intermediate
INCOME Intermediate value Government led by Scott Amero, Keith Government Income
Government Anderson & Todd Kopstein
SSR HEALTH Shell Keep active Lipper Health/Bio- Merged team led by Erin Xie SSR Health Sciences
SCIENCES fundamental technology Funds Index (SSR) & Thomas Callan (BLK)
SSR HIGH INCOME BLK High Yield Keep relative Lehman US BLK fixed income team led by BLK High Yield
value Corporate HY Scott Amero & Jeff Gary
SSR INVESTMENT BLK Select Change to S&P 500 BLK quantitative equity team BLK Select Equity
TRUST Equity active quant led by David Byrket & Fred
Herrmann
SSR LARGE-CAP BLK Select Change to S&P 500 BLK quantitative equity team BLK Select Equity
ANALYST Equity active quant led by David Byrket & Fred
Herrmann
SSR LARGE-CAP BLK Large-Cap Change to Russell 1000(R) Value BLK quantitative equity team BLK Large-Cap
VALUE Value active quant led by David Byrket & Fred Value
Herrmann
SSR LEGACY BLK Legacy Keep active Russell 1000(R) Growth SSR large-cap growth team led SSR Legacy
fundamental by Ed Dowd & Jeff Lindsey
SSR MID-CAP BLK Mid-Cap Keep active Russell Midcap(R) Growth Merged team led by Eileen BLK Mid-Cap
GROWTH Growth fundamental Leary (SSR) & Neil Wagner Growth
(BLK)
SSR MID-CAP BLK Mid- Keep active Russell Midcap(R) Value Merged team led by Anthony SSR Mid-Cap Value
VALUE Cap Value fundamental Forcione (SSR) & Wayne
Archambo (BLK)
SSR MONEY BLK Money Keep relative Lipper Money Market BLK Institutional Management BLK Money Market
MARKET Market value Funds Index Corp.
</Table>
*SSR: State Street Research; BLK: BlackRock
The information above is as of November 2004 and is subject to change. The
reorganizations are subject to shareholder approval and the closing of
BlackRock's aquisition of SSRM.
FOR USE WITH BROKER/DEALERS ONLY.
NO PORTION OF THIS PUBLICATION MAY BE SHOWN OR DISTRIBUTED TO THE PUBLIC OR USED
IN ORAL OR WRITTEN FORM IN SOLICITING SALES.
Member NASD, SIPC
(C) 2004 State Street Research Investment Services, Inc.
One Financial Center
Boston, MA 02111-2690
www.ssrfunds.com
CONTROL NUMBER:(exp0205)SSR-LD SSR-9095-1104