Exhibit 3.5

                             CERTIFICATE OF INCREASE

                                       OF

                                SHARES DESIGNATED

                                       AS

                  SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

                                    * * * * *

            Brooks Automation, Inc., a corporation organized and existing under
the General Corporation Law of the State of Delaware,

            DOES HEREBY CERTIFY:

            That a Certificate of the Designations, Preferences and Rights of
the Preferred Stock, Series A Junior Participating Preferred Stock, was filed in
the office of the Secretary of State on August 6, 1997.

            That the Board of Directors of said corporation by the unanimous
written consent of its members dated May 13, 2002, filed with the minutes of the
Board, duly adopted a resolution authorizing and directing an increase in the
number of shares designated as Series A Junior Participating Preferred stock of
the corporation, from 21,500 shares to 101,500 shares, in accordance with the
provisions of section 151 of The General Corporation Law of the State of
Delaware.

            This Certificate of Increase of Shares shall be effective on May 13,
2002.

            IN WITNESS WHEREOF, said Brooks Automation, Inc. has caused this
certificate to be signed by Ellen B. Richstone, its Senior Vice President,
Finance and Administration and Chief Financial Officer this 13th day of May,
2002.

                                   BROOKS AUTOMATION, INC.

                                   By: /s/ Ellen B. Richstone
                                       -------------------------
                                   Name: Ellen B. Richstone
                                   Title: Senior Vice President,
                                          Finance and Administration and
                                          Chief Financial Officer