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                                                                   EXHIBIT 3.1.2

                             CERTIFICATE OF DECREASE

                                     OF THE

                           SERIES A PREFERENCE STOCK

                                       OF

                             PICTURETEL CORPORATION

                        Pursuant to Section 151(g) of the

                        Delaware General Corporations Law

     Reference is made to the Certificate Of Designation, Preferences And Other
Rights of the Series A Preference Stock ("THE SERIES A CERTIFICATE OF
DESIGNATION") of PictureTel Corporation, a corporation organized and existing
under the laws of the State of Delaware (the "CORPORATION"), which certificate
was dated February 15, 1999 and was duly filed with the Secretary of State of
the State of Delaware on February 16, 1999.

     PictureTel Corporation hereby certifies that, pursuant to the Certificate
of Incorporation of the Corporation, as amended, and in accordance with Section
151(g) of the Delaware General Corporations Law, the Board of Directors of the
Corporation on July 11, 2000 duly adopted the following resolution, which
resolution remains in full force and effect as of the date hereof:

     "RESOLVED, that pursuant to the authority granted to and vested in the
Board of Directors and in accordance with the provisions of the Certificate of
Incorporation, the number of shares of Series A Preference Stock designated in
the Certificate Of Designation, Preferences And Other Rights ("THE SERIES A
CERTIFICATE OF DESIGNATION") of this Corporation is reduced, subject to the
filing of the Certificate of Decrease with the Secretary of State of the State
of Delaware, as set forth below:

     1.   Section 1 of the Certificate of Designation is amended by replacing
          the words "Six Million (6,000,000)" in the second sentence with the
          words "Four Million Five Hundred Thousand (4,500,000)".


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     IN WITNESS WHEREOF, the Corporation has caused this Certificate of Decrease
to be executed by a duly authorized officer on July 17, 2000.


                                       PICTURETEL CORPORATION


                                       By:    ______________________________

                                       Name:  ______________________________

                                       Title: ______________________________


Certif. of Desig. Series A. decrease

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