FILED BY: GSLI CORP

                        PURSUANT TO RULE 165 AND 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.
                         COMMISSION FILE NO.: 000-25705


                     GSI LUMONICS INC. ANNOUNCES CHANGES TO
                 SCHEDULING OF SPECIAL MEETING OF SHAREHOLDERS



     BILLERICA, MASSACHUSETTS (JUNE 27, 2003): GSI Lumonics Inc. (NASDAQ: GSLI
and TSX: LSI) today announced that a special meeting of its shareholders,
originally scheduled to be held on Thursday, July 24, 2003, will now be held at
10:00 a.m. on Monday, August 4, 2003 at the Renaissance Bedford Hotel in
Bedford, Massachusetts.

     At the meeting, shareholders and optionholders will be asked to consider
the approval of a plan of arrangement, the principal effect of which will be to
restructure the Company as a publicly traded United States domiciled
corporation. Detailed information on the plan of arrangement, including the
applicable reasons, mechanics, effects and risks associated therewith, is
contained in the registration statement on Form S-4 filed by GSLI Corp, the
Company's wholly-owned subsidiary, with the Securities and Exchange Commission.
Shareholders and optionholders wishing to do so may obtain a copy of GSLI Corp's
Form S-4 and any amendments thereto 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 GSI Lumonics Inc.'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 GSI Lumonics Inc., similar risks
to GSI Lumonics Inc. of delays in its new products, its ability to continue to
reduce costs and capital expenditures, its ability to focus R&D investment, the
risk that the proposed arrangement will not be completed and the other risks
associated therewith, including risks detailed in GSI Lumonics Inc.'s Annual
Reports on Form 10-K and Quarterly Reports on Form 10-Q and GSLI Corp's
Registration Statement on Form S-4.


ADDITIONAL INFORMATION ABOUT THE ARRANGEMENT 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
arrangement 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. Shareholders of GSI Lumonics Inc. are urged to read the registration
statement because it contains important information, including detailed risk
factors relating to the proposed arrangement, not contained in this news
release. A definitive proxy circular-prospectus will be sent to shareholders of
GSI Lumonics Inc. seeking their approval of the proposed arrangement.
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 by shareholders without charge by directing a request to
GSI Lumonics Inc., 39 Manning Road, Billerica, Massachusetts, 01821, Attn:
Investor Relations.


PARTICIPANTS IN SOLICITATION

     GSI Lumonics Inc., 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 Inc. in connection
with the proposed arrangement. Information concerning GSI Lumonics Inc.'s and
GSLI Corp's participants in the solicitation is set forth in GSI Lumonics Inc.'s
management proxy circular for the 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. Certain directors and executive officers of
GSI Lumonics Inc. and GSLI Corp may have direct or indirect interests in the
arrangement due to securities holdings, vesting of options and pre-existing or
future indemnification arrangements. Additional information regarding GSI
Lumonics Inc., GSLI Corp and the interests of their respective directors and
executive officers in the arrangement is contained in the proxy
circular-prospectus which, as noted above, is a part of GSLI Corp's Registration
Statement on Form S-4.


ABOUT GSI LUMONICS INC.

     GSI Lumonics Inc. supplies precision motion control components, lasers and
laser-based advanced manufacturing systems to the global medical, semiconductor,
electronics and industrial markets. Its common shares are listed on The NASDAQ
Stock Market(R) (GSLI) and the Toronto Stock Exchange (LSI). The Company's
Internet website address is http://www.gsilumonics.com/.

     For more information, please contact:

         Thomas R. Swain
         GSI Lumonics Inc.
         (978) 439-5511, ext. 6102