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                                                                     Exhibit 3.5

                            CERTIFICATE OF AMENDMENT
                                       OF
                          CERTIFICATE OF INCORPORATION
                                       OF
                            IPG PHOTONICS CORPORATION

         IPG PHOTONICS CORPORATION, a corporation duly organized and existing
under the General Corporation Law of the State of Delaware (the "Corporation"),
does hereby certify that:

         1. The Certificate of Incorporation of the Corporation is hereby
amended by inserting the following immediately after the first paragraph of
Article FOURTH thereof:

                  "Upon the Certificate of Amendment to the Certificate of
         Incorporation of the Corporation (the "Certificate of Amendment")
         becoming effective pursuant to the General Corporation Law of the State
         of Delaware (the "Effective Time"), each share of Common Stock issued
         and outstanding immediately prior to the Effective Time (the "Old
         Common Stock") will be automatically reclassified as and converted into
         a fraction (the "Fraction") of a share of Common Stock (the "New Common
         Stock") which shall be set forth in a resolution adopted by the Board
         of Directors and shall be set forth in the Certificate of Amendment.
         Any stock certificate that, immediately prior to the Effective Time,
         represented shares of Old Common Stock will, from and after the
         Effective Time, automatically and without the necessity of presenting
         the same for exchange, represent the number of shares of New Common
         Stock as equals the product obtained by multiplying the Fraction by the
         number of shares of Old Common Stock represented by such certificate
         immediately prior to the Effective Time. Notwithstanding the foregoing,
         no person shall hold a fractional share of New Common Stock as a result
         of the foregoing reclassification of the Old Common Stock, but, instead
         of any fraction of a share that would otherwise result from such
         reclassification, the Corporation shall, upon the surrender for
         cancellation by any former holder of Old Common Stock of any
         certificate formerly representing shares of Old Common Stock pay cash
         in respect of such fraction in an amount equal to the fair market value
         of such shares as determined by the Board of Directors."


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         2. The foregoing amendment was duly adopted in accordance with the
provisions of Section 242 of the General Corporation Law of the State of
Delaware.

         3. The Board of Directors of the Corporation duly adopted a unanimous
written consent, dated December __, 2006, approving a reclassification of the
outstanding shares of Common Stock, par value of $.0001 per share, of the
Corporation on a two-for-three basis (so that (i) each share of Old Common Stock
(as defined above) outstanding immediately prior to the effective time of the
reclassification shall be reclassified into 2/3 of a share of New Common Stock
immediately following the reclassification and (ii) any person holding a
fractional share of New Common Stock as the result of such reclassification (in
excess of the aggregate number of whole shares of New Common Stock held by such
person as the result of such reclassification) shall be entitled to receive cash
in lieu of fractional shares in an amount to be determined by the Board of
Directors) to become effective upon filing of a Certificate of Amendment to the
Certificate of Incorporation with respect to the reclassification.

                            [Signature Page Follows]

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         IN WITNESS WHEREOF, the Corporation has caused this Certificate to be
executed by its duly authorized officer on this ___ day of _______________,
2006.


                                By:
                                   ---------------------------------------------
                                         Name:
                                         Office:



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