FILED BY: GSLI CORP

                               PURSUANT TO RULE 425
                  UNDER THE SECURITIES ACT OF 1933, AS AMENDED
                    AND DEEMED FILED PURSUANT TO RULE 14A-12
              UNDER THE SECURITIES EXCHANGE ACT OF 1934, AS AMENDED

                       SUBJECT COMPANY: GSI LUMONICS INC.
                     REGISTRATION STATEMENT NO.: 333-104138


                        GSI LUMONICS REPORTS SEC FILINGS


BILLERICA, MASSACHUSETTS (MARCH 31, 2003): GSI Lumonics Inc. (NASDAQ: GSLI and
TSX: LSI) today filed with the Securities and Exchange Commission its annual
report on Form 10-K for the fiscal year ended December 31, 2002. Additionally,
the Company's newly formed Delaware subsidiary, GSLI Corp, filed a registration
statement on Form S-4, containing a preliminary copy of a joint proxy
circular-prospectus in conjunction with GSI Lumonics' annual meeting of
shareholders scheduled for June 24, 2003.

The principal business of the annual meeting of shareholders is the election of
the directors to the Board and a proposal to reorganize the Company as a
publicly traded U.S. domiciled corporation. Most of the Company's operations and
all of its executive management are located in the United States. If this
proposal is implemented, GSLI Corp would become the parent holding company for
GSI Lumonics. GSI Lumonics shareholders would become stockholders of GSLI Corp,
subject to the right of Canadian resident shareholders to elect, for reasons
unique to Canadian residents, to remain shareholders of GSI Lumonics and to
receive exchangeable shares. The exchangeable shares would be exchangeable for
shares of GSLI Corp. The day-to-day operations of the Company will not
materially change as a result of this proposed reorganization.

DETAILED INFORMATION ON THIS PROPOSED TRANSACTION, INCLUDING THE APPLICABLE
REASONS, MECHANICS, EFFECTS AND RISKS ASSOCIATED THEREWITH, ARE CONTAINED IN THE
FORM S-4 GSLI CORP FILED WITH THE SECURITIES AND EXCHANGE COMMISSION. YOU CAN
OBTAIN A COPY OF GSLI CORP'S FORM S-4 AT HTTP://WWW.SEC.GOV.

FORWARD-LOOKING STATEMENTS

To the extent this news release discusses financial projections, information or
expectations about GSI Lumonics Inc., proposed transactions, products or
markets, or otherwise makes statements about the future, such statements are
forward looking and are subject to a number of risks and uncertainties that
could cause actual results to differ materially from the statements made. The
factors include the fact that the Company's sales have been and are expected to
continue to be dependent upon customer capital equipment expenditures, which
are, in turn, affected by business cycles in the markets served by those
customers. Other factors include volatility in the semiconductor industry, the
risk of order delays and cancellations, the risk of delays by customers in
introducing their new products and market acceptance of products incorporating
subsystems supplied by the Company, similar risks to the Company of delays in
its new products, our ability to continue to reduce costs and capital
expenditures, our ability to focus R&D investment, the risk that the proposed
reincorporation will not be completed and the other risks associated therewith,
including risks detailed in the Company's Annual Reports on Form 10-K and
Quarterly Reports on Form 10-Q and GSLI Corp's Form S-4.

ADDITIONAL INFORMATION ABOUT THE PROPOSED TRANSACTION AND WHERE TO FIND IT

GSLI Corp has filed with the Securities and Exchange Commission a Registration
Statement on Form S-4 and other documents regarding the proposed transaction
referenced in this news release. This news release does not constitute an offer
to sell or the solicitation of an offer to buy securities of GSLI Corp. GSI
Lumonics shareholders are urged to read the registration statement because it
contains important information, including detailed risk factors relating to
the proposed transaction, not contained in this news release. A definitive
proxy circular-prospectus will


be sent to shareholders of GSI Lumonics seeking their approval of the proposed
transaction. GSI Lumonics shareholders may obtain free copies of the
registration statement, the proxy circular-prospectus (when it becomes
available) and other documents filed by GSLI Corp with the Securities and
Exchange Commission on the Internet at http://www.sec.gov. The registration
statement, the proxy circular-prospectus and these other documents may also be
obtained without charge by GSI Lumonics shareholders by directing a request to
GSI Lumonics, 39 Manning Road, Billerica, Massachusetts, 01821, Attn: Investor
Relations.

PARTICIPANTS IN SOLICITATION

GSI Lumonics, GSLI Corp and their respective directors, executive officers and
other members of management and employees may be participating in the
solicitation of proxies from shareholders of GSI Lumonics in connection with the
proposed transaction. Information concerning GSI Lumonics' and GSLI Corp's
participants in the solicitation is set forth in GSI Lumonics' management proxy
circular for the annual and special meeting of shareholders, which is a part of
the Registration Statement on Form S-4 filed by GSLI Corp with the Securities
and Exchange Commission on March 31, 2003. Certain directors and executive
officers of GSI Lumonics and GSLI Corp may have direct or indirect interests in
the proposed transaction due to securities holdings, vesting of options and
pre-existing or future indemnification arrangements. Additional information
regarding GSI Lumonics, GSLI Corp and the interest of their respective
directors, executive officers in the proposed transaction is contained in the
proxy circular-prospectus which, as noted above, is a part of the Registration
Statement on Form S-4.

ABOUT GSI LUMONICS INC.

GSI Lumonics supplies components, lasers and laser-based advanced manufacturing
systems to the global medical, automotive, semiconductor, electronics, and
industrial markets. GSI Lumonics' common shares are listed on The NASDAQ Stock
Market(R) (GSLI) and The Toronto Stock Exchange (LSI). The Company's web site
address is www.gsilumonics.com.



         For more information, please contact:

         Victor Woolley
         GSI Lumonics Inc.
         978-439-5511, Ext. 6135