UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                 SCHEDULE 13D/A
                    Under the Securities Exchange Act of 1934

                                 Amendment No. 1

                                 GSI Group Inc.
--------------------------------------------------------------------------------
                                (Name of Issuer)

                           Common Stock, no par value
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    36229U102
--------------------------------------------------------------------------------
                                 (CUSIP Number)

                                Stephanie S. Chen
                          c/o Tinicum Lantern II L.L.C.
                          800 Third Avenue, 40th Floor
                               New York, NY 10022
                                  212-446-9300

--------------------------------------------------------------------------------
(Name, Address and Telephone Number of Person Authorized to Receive Notices and
                                 Communications)

                                February 26, 2010
                               ------------------
             (Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report
the acquisition that is the subject of this Schedule 13D, and is filing this
schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g), check the following box
[ ].

Note: Schedules filed in paper format shall include a signed original and five
copies of the schedule, including all exhibits. See Rule 13d-7 for other parties
to whom copies are to be sent.

--------------------
* The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter
disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).

                         (Continued on following pages)
                               (Page 1 of 7 Pages)







----------------------------                        ----------------------------
CUSIP No.  36229U102            SCHEDULE 13D/A        Page 2 of 7 Pages
----------------------------                        ----------------------------
------------- -----------------------------------------------------------------
     1        NAME OF REPORTING PERSON

              Tinicum Capital Partners II, L.P.
------------- -----------------------------------------------------------------
     2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |_|  (b) |X|

------------- -----------------------------------------------------------------
     3        SEC USE ONLY
------------- -----------------------------------------------------------------
     4        SOURCE OF FUNDS

              WC, OO
------------- -----------------------------------------------------------------
     5        CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
              TO ITEMS 2(d) or 2(e)     |_|
------------- -----------------------------------------------------------------
     6        CITIZENSHIP OR PLACE OF ORGANIZATION

              Delaware
------------- -----------------------------------------------------------------
 NUMBER OF    7           SOLE VOTING POWER

   SHARES                 0
              ----------- -----------------------------------------------------
BENEFICIALLY  8           SHARED VOTING POWER

   OWNED                  418,464
              ----------- -----------------------------------------------------
  BY EACH     9           SOLE DISPOSITIVE POWER

 REPORTING                0
              ----------- -----------------------------------------------------
  PERSON      10          SHARED DISPOSITIVE POWER

                          418,464
------------- ----------- -----------------------------------------------------
     11       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              418,464
------------- -----------------------------------------------------------------
     12       CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
              SHARES |_|
------------- -----------------------------------------------------------------
     13       PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11

              0.8% (see Item 4)
------------- -----------------------------------------------------------------
     14       TYPE OF REPORTING PERSON
              PN
------------- -----------------------------------------------------------------







----------------------------                        ----------------------------
CUSIP No.  36229U102            SCHEDULE 13D/A        Page 3 of 7 Pages
----------------------------                        ----------------------------
------------- -----------------------------------------------------------------
     1        NAME OF REPORTING PERSON

              Tinicum Lantern II L.L.C.

------------- -----------------------------------------------------------------
     2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |_|  (b) |X|

------------- -----------------------------------------------------------------
     3        SEC USE ONLY
------------- -----------------------------------------------------------------
     4        SOURCE OF FUNDS

              AF
------------- -----------------------------------------------------------------
     5        CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
              TO ITEMS 2(d) or 2(e)     |_|
------------- -----------------------------------------------------------------
     6        CITIZENSHIP OR PLACE OF ORGANIZATION

              Delaware
------------- -----------------------------------------------------------------
 NUMBER OF    7           SOLE VOTING POWER

   SHARES                 0
              ----------- -----------------------------------------------------
BENEFICIALLY  8           SHARED VOTING POWER

   OWNED                  418,464
              ----------- -----------------------------------------------------
  BY EACH     9           SOLE DISPOSITIVE POWER

 REPORTING                0
              ----------- -----------------------------------------------------
  PERSON      10          SHARED DISPOSITIVE POWER

                          418,464
------------- ----------- -----------------------------------------------------
     11       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              418,464
------------- -----------------------------------------------------------------
     12       CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
              SHARES |_|
------------- -----------------------------------------------------------------
     13       PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11

              0.8% (see Item 4)
------------- -----------------------------------------------------------------
     14       TYPE OF REPORTING PERSON
              OO
------------- -----------------------------------------------------------------







----------------------------                        ----------------------------
CUSIP No.  36229U102            SCHEDULE 13D/A        Page 4 of 7 Pages
----------------------------                        ----------------------------
------------- -----------------------------------------------------------------
     1        NAME OF REPORTING PERSON

              Terence M. O'Toole

------------- -----------------------------------------------------------------
     2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |_|  (b) |X|

------------- -----------------------------------------------------------------
     3        SEC USE ONLY
------------- -----------------------------------------------------------------
     4        SOURCE OF FUNDS

              AF
------------- -----------------------------------------------------------------
     5        CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
              TO ITEMS 2(d) or 2(e)     |_|
------------- -----------------------------------------------------------------
     6        CITIZENSHIP OR PLACE OF ORGANIZATION

              United States
------------- -----------------------------------------------------------------
 NUMBER OF    7           SOLE VOTING POWER

   SHARES                 0
              ----------- -----------------------------------------------------
BENEFICIALLY  8           SHARED VOTING POWER

   OWNED                  418,464
              ----------- -----------------------------------------------------
  BY EACH     9           SOLE DISPOSITIVE POWER

 REPORTING                0
              ----------- -----------------------------------------------------
  PERSON      10          SHARED DISPOSITIVE POWER

                          418,464
------------- ----------- -----------------------------------------------------
     11       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              418,464
------------- -----------------------------------------------------------------
     12       CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
              SHARES |_|
------------- -----------------------------------------------------------------
     13       PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11

              0.8% (see Item 4)
------------- -----------------------------------------------------------------
     14       TYPE OF REPORTING PERSON
              IN
------------- -----------------------------------------------------------------







----------------------------                        ----------------------------
CUSIP No.  36229U102            SCHEDULE 13D/A        Page 5 of 7 Pages
----------------------------                        ----------------------------
------------- -----------------------------------------------------------------
     1        NAME OF REPORTING PERSON

              Eric M. Ruttenberg

------------- -----------------------------------------------------------------
     2        CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (a) |_|  (b) |X|

------------- -----------------------------------------------------------------
     3        SEC USE ONLY
------------- -----------------------------------------------------------------
     4        SOURCE OF FUNDS

              AF
------------- -----------------------------------------------------------------
     5        CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT
              TO ITEMS 2(d) or 2(e)     |_|
------------- -----------------------------------------------------------------
     6        CITIZENSHIP OR PLACE OF ORGANIZATION

              United States
------------- -----------------------------------------------------------------
 NUMBER OF    7           SOLE VOTING POWER

   SHARES                 0
              ----------- -----------------------------------------------------
BENEFICIALLY  8           SHARED VOTING POWER

   OWNED                  418,464
              ----------- -----------------------------------------------------
  BY EACH     9           SOLE DISPOSITIVE POWER

 REPORTING                0
              ----------- -----------------------------------------------------
  PERSON      10          SHARED DISPOSITIVE POWER

                          418,464
------------- ----------- -----------------------------------------------------
     11       AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

              418,464
------------- -----------------------------------------------------------------
     12       CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN
              SHARES |_|
------------- -----------------------------------------------------------------
     13       PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 11

              0.8% (see Item 4)
------------- -----------------------------------------------------------------
     14       TYPE OF REPORTING PERSON
              IN
------------- -----------------------------------------------------------------







----------------------------                        ----------------------------
CUSIP No.  36229U102            SCHEDULE 13D/A        Page 6 of 7 Pages
----------------------------                        ----------------------------

ITEM 1.       SECURITY AND ISSUER

     This Amendment No. 1 (the "Amendment") amends the statement on Schedule 13D
filed on  January  13,  2010 (the  "Original  Schedule  13D",  as  amended,  the
"Schedule  13D") with respect to the common stock,  no par value (the "Shares"),
of GSI  Group  Inc.,  a company  continued  and  existing  under the laws of the
Province of New Brunswick, Canada (the "Issuer").  Capitalized terms used herein
and not otherwise  defined in this  Amendment have the meanings set forth in the
Original Schedule 13D. This Amendment amends Item 4 as set forth below.

Item 4 of the Schedule 13D is hereby amended and supplemented by the addition of
the following:

     As previously disclosed, the Reporting Persons continue to have discussions
with  the  Issuer  and  other  shareholders  regarding  the  Reporting  Persons'
investment and implementation of the Plan. In furtherance of this, the Reporting
Persons have entered into  discussions with the Issuer and members of the Equity
Committee regarding the Plan and possible  modifications to the Plan, including,
without  limitation,  exchanging the Notes for any combination of one or more of
the  following:  new secured debt,  notes  convertible  into common stock of the
reorganized  issues,  preferred  stock  convertible  into  common  stock  of the
reorganized  issues,  common stock of the  reorganized  issues and/or cash.  The
Reporting  Persons are unsure about the ultimate  outcome of such discussions or
the timing of coming to agreement.






----------------------------                        ----------------------------
CUSIP No.  36229U102            SCHEDULE 13D        Page 7 of 7 Pages
----------------------------                        ----------------------------

                                    Signature

     After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete and
correct.

     Dated: March 3, 2010

                                    /s/ Eric M. Ruttenberg
                                    ----------------------
                                    TINICUM LANTERN II L.L.C.,
                                    On its own behalf and
                                    as the General Partner of
                                    TINICUM CAPITAL PARTNERS II, L.P.
                                    By Eric M. Ruttenberg,
                                    Managing Member

                                    /s/ Terence M. O'Toole
                                    ----------------------
                                    Terence M. O'Toole

                                    /s/ Eric M. Ruttenberg
                                    ----------------------
                                    Eric M. Ruttenberg