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                                                                  Exhibit 10.8c

                                                                  EXECUTION COPY



                           AMENDMENT NUMBER 3 TO THE
                                CREDIT AGREEMENT

                         Dated as of December 19, 1996



            This AMENDMENT NUMBER 3 (the "Amendment") among The Geon Company, a
Delaware corporation (the "Borrower"), the banks, financial institutions and
institutional lenders parties to the Credit Agreement referred to below (the
"Lenders"), and Citibank, N.A. ("Citibank"), as administrative agent (the
"Administrative Agent") for the Lenders, and NationsBank, N.A., as co-agent (the
"Co-Agent") thereunder.

            PRELIMINARY STATEMENTS:

            (1) The Borrower, the Lenders, the Administrative Agent and the
Co-Agent have entered into a Credit Agreement dated as of August 16, 1994, and
the amendments thereto dated as of December 8, 1994, and November 9, 1995,
respectively (such Credit Agreement, as so amended and as otherwise supplemented
or modified through the date hereof, the "Credit Agreement"). Capitalized terms
not otherwise defined in this Amendment are used herein as defined in the Credit
Agreement.

            (2) The Borrower and the Lenders have agreed to amend the Credit
Agreement as hereinafter set forth.

            SECTION 1. Amendments to Credit Agreement. The Credit Agreement is,
effective as of the date hereof and subject to the satisfaction of the
conditions precedent set forth in Section 2 hereof, hereby amended as follows:

                  (a) The definition of "Applicable Margin" in Section 1.01 is
            amended by deleting the table in clause (ii) thereof and
            substituting therefor the following:
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<TABLE>
<CAPTION>
                                                           Applicable
Public Debt Rating                                             for
   S&P/Moody's/                                          Eurodollar Rate
  Duff & Phelps                 Usage                        Advances
------------------------------------------------------------------------
<S>                         <C>                         <C>
Level 1                      less than or equal to 50%         0.150%
A-/A3/A- or above            greater than 50%                  0.200%

Level 2                      less than or equal to 50%         0.175%
BBB+/Baa1/BBB+               greater than 50%                  0.225%

Level 3                      less than or equal to 50%         0.225%
BBB/Baa2/BBB                 greater than 50%                  0.300%

Level 4                      less than or equal to 50%         0.2175%
BBB-/Baa3/BBB-               greater than 50%                  0.2875%

Level 5                      less than or equal to 50%         0.375%
BB+/Ba1/BB+                  greater than 50%                  0.500%

Level 6                      less than or equal to 50%         0.625%
BB/Ba2/BB                    greater than 50%                  0.750%
</TABLE>
 


            (b) The definition of "LaPorte Financing" in Section 1.01 is amended
      in full to read as follows:

                  "'LaPorte Financing' means, collectively, the transactions
            contemplated by (i) the Amended and Restated Participation Agreement
            dated as of December 19, 1996 (the "Participation Agreement") among
            the Borrower, 1994 VCM Inc., State Street Bank and Trust Company of
            Connecticut, National Association, as trustee, the financial
            institutions parties thereto and Citibank, N.A., as agent, and (ii)
            the other Operative Documents (as defined in the Participation
            Agreement)."

            (c) The definition of "Termination Date" in Section 1.01 is amended
      by deleting the date "August 16, 1999" and substituting therefor the date
      "December 19, 2001".

            SECTION 2. Conditions of Effectiveness. This Amendment shall become
effective when, and only when, on or before December 19, 1996, the
Administrative Agent shall have received (a) counterparts of this Amendment
executed by the Borrower and all of the Lenders or, as to any of the Lenders,
advice satisfactory to the Administrative Agent that such Lenders have executed
this
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Amendment and (b) a certificate signed by a duly authorized officer of the
Borrower, in form and substance satisfactory to the Administrative Agent and
dated the date of receipt thereof by the Administrative Agent, stating that:

                  (i) The representations and warranties contained in Section 3
            hereof are correct on and as of the date of such certificate as
            though made on and as of such date, and

                  (ii) No event has occurred and is continuing which constitutes
            an Event of Default or would constitute an Event of Default but for
            the requirement that notice be given or time elapse or both.

            SECTION 3. Representations and Warranties of the Borrower. The
Borrower represents and warrants as follows:

            (a) The Borrower is a corporation duly organized, validly existing
      and in good standing under the laws of the jurisdiction indicated at the
      beginning of this Amendment.

            (b) The execution, delivery and performance by the Borrower of this
      Amendment and the Credit Agreement, as amended hereby, are within the
      Borrower's corporate powers, have been duly authorized by all necessary
      corporate action and do not contravene (i) the Borrower's charter or
      by-laws, (ii) law or any contractual restriction binding on or affecting
      the Borrower.

            (c) No authorization, approval or other action by, and no notice to
      or filing with, any governmental authority or regulatory body is required
      for the due execution, delivery and performance by the Borrower of this
      Amendment or the Credit Agreement, as amended hereby.

            (d) This Amendment and the Credit Agreement, as amended hereby,
      constitute legal, valid and binding obligations of the Borrower
      enforceable against the Borrower in accordance with their respective
      terms.

            (e) To the best of the Borrower's knowledge, there is no pending or
      threatened action, suit, investigation, litigation or proceeding,
      including, without limitation, any Environmental Action, affecting the
      Borrower or any of its Subsidiaries before any court, governmental agency
      or arbitrator that (i) could be reasonably likely to have a Material
      Adverse Effect (other than the Disclosed Litigation as described on
      Schedule 3.01(b) of the Credit Agreement and as described on Schedule A
      hereto (collectively, the "Current Litigation")) or (ii) purports to
      affect the legality, validity or enforceability of this Amendment, the
      Credit Agreement as amended hereby or any Note or the consummation of the
      transactions contemplated hereby, and there has been no adverse change in
      the status, or financial effect on the Borrower or any of its
      Subsidiaries, of the Current Litigation from that described on Schedule
      3.01(b) of the Credit Agreement and on Schedule A hereto.
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            SECTION 4. Reference to and Effect on the Credit Agreement and
Notes. (a) Upon the effectiveness of Section 1 hereof, on and after the date
hereof each reference in the Credit Agreement to "this Agreement", "hereunder",
"hereof" or words of like import referring to the Credit Agreement, and each
reference in the other Notes to "the Credit Agreement", "thereunder", "thereof"
or words of like import referring to the Credit Agreement, shall mean and be a
reference to the Credit Agreement as amended hereby.

            (b) Except as specifically amended above, the Credit Agreement and
the Notes are and shall continue to be in full force and effect and are hereby
in all respects ratified and confirmed.

            SECTION 5. Costs and Expenses. The Borrower agrees to pay on demand
all costs and expenses of the Administrative Agent in connection with the
preparation, execution, delivery, administration, modification and amendment of
this Amendment and the other instruments and documents to be delivered
hereunder, including, without limitation, the reasonable fees and out-of-pocket
expenses of counsel for the Administrative Agent with respect thereto and with
respect to advising the Administrative Agent as to its rights and
responsibilities hereunder and thereunder.

            SECTION 6. Execution in Counterparts. This Amendment may be executed
in any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed and delivered shall be deemed to be
an original and all of which taken together shall constitute but one and the
same agreement. Delivery of an executed counterpart of a signature page of this
Amendment by telecopier shall be effective as delivery of a manually executed
counterpart of this Amendment.

            SECTION 7. Governing Law. This Amendment shall be governed by, and
construed in accordance with, the laws of the State of New York.

            IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
be executed by their respective officers thereunto duly authorized, as of the
date first above written.

                                        THE GEON COMPANY


                                        By 
                                          -----------------------------
                                          Title: Assistant Treasurer


                                        CITIBANK, N.A.
                                         as Administrative Agent and as Lender


                                        By 
                                          -----------------------------
                                          Title: ATTORNEY-IN-FACT
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                                        NATIONSBANK, N.A.,
                                         as Co-Agent and as Lender

                                        By
                                          -----------------------------
                                          Title: VP


                                        BANK OF MONTREAL


                                        By
                                          -----------------------------
                                          Title:


                                        THE BANK OF NEW YORK


                                        By
                                          -----------------------------
                                          Title: Vice President

                                        CANADIAN IMPERIAL BANK OF
                                         COMMERCE

                                        By
                                          -----------------------------
                                          Title: Authorized Signatory


                                        MORGAN GUARANTY TRUST
                                         COMPANY OF NEW YORK


                                        By 
                                          -----------------------------
                                          Title: Vice President


                                        NBD BANK, N.A.


                                        By
                                          -----------------------------
                                          Title: First Vice President
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                                        NATIONAL CITY BANK


                                        By
                                          ---------------------------------
                                          Title: V.P. & Sr. Lending Officer