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                                                                   Exhibit 10.12


                               FIRST AMENDMENT TO
                     MEMBERSHIP INTERESTS PURCHASE AGREEMENT

      This FIRST AMENDMENT (the "Amendment") to the MEMBERSHIP INTERESTS
PURCHASE AGREEMENT dated as of July 22, 1999, by and between Charter
Communications Holding Company, LLC (the "Company") and Paul G. Allen (the
"Buyer"), is entered into as of August 10, 1999.

                                    RECITALS

      A. The Company and Buyer entered into that certain Membership Interests
Purchase Agreement dated as of July 22, 1999 (the "Purchase Agreement")
providing for, among other things, the purchase and sale of membership interests
to the Buyer in two closings, the first to occur on or before July 30, 1999, and
the second to occur after July 30, 1999 and on or before September 1, 1999.

      B. The First Closing occurred on August 10, 1999, and in connection
therewith, Vulcan Cable III Inc. ("Vulcan"), a Washington corporation
wholly-owned by the Buyer, acquired the First Issuance Acquired Membership
Interests for a purchase price of $500 million.

      C. Vulcan has assumed the obligations of one of the Company's subsidiaries
to purchase certain equity and debt from the stockholders of three corporate
partners (the "Blocker Corporations") of InterLink Communications Partners, LLLP
(or its successor) ("InterLink").

      D. The parties to the Purchase Agreement desire to amend the Purchase
Agreement to reflect a change in the timing and manner in which the Buyer will
purchase an additional 39,797,395 Units (the "Second Tranche") for $825 million
in the form of cash and membership interests in InterLink to be contributed to
the Company.

      E. Capitalized terms used in this Amendment shall have the meaning
ascribed to them in the Purchase Agreement.

                                    AGREEMENT

      In consideration of the mutual premises contained herein and intending to
be legally bound, the parties agree that the Purchase Agreement is hereby
amended as follows:

      1. Section 1 of the Purchase Agreement is hereby amended and restated in
its entirety as follows:

            "1. Purchase and Sale of Membership Interests. On the terms and
subject to the conditions contained in this Agreement, the Company hereby agrees
to issue and sell to Buyer or his designee, and Buyer hereby agrees to purchase
or cause to be purchased from the Company, (a) at the First Closing (as defined
below), 24,119,633 Units for an aggregate purchase price of Five Hundred Million


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Dollars ($500,000,000) (the 'FIRST ISSUANCE ACQUIRED MEMBERSHIP INTEREST'), (b)
at the Second Closing (as defined below), a number of Units equal to the Second
Closing Cash Amount (as defined below) divided by $20.73 (the 'SECOND ISSUANCE
ACQUIRED MEMBERSHIP INTEREST'), for an aggregate purchase price equal to the
Second Closing Cash Amount, and (c) at the Third Closing (as defined in Section
2(c) below), the portion of the Second Tranche not purchased in the Second
Closing (the 'THIRD ISSUANCE ACQUIRED MEMBERSHIP INTEREST'), in consideration of
(x) the contribution to the Company of the InterLink Interest (as defined in
Section 2(c) below), (y) the assignment to the Company of all of Vulcan's right
to and interest in any indemnification payments or other amounts that may be
payable to it or by it (other than the Final Blocker Price) under the InterLink
Agreement (as defined below), and (z) the commitment made hereby to pay to the
Company the Excess Cash (as defined below), if any. As used in this Agreement,
the following terms have the following meanings:

            (a) 'Estimated Blocker Price' means the maximum amount, estimated by
      Vulcan in good faith immediately prior to the Second Closing, that Vulcan
      will be required to pay to acquire the Blocker Corporations from the
      owners thereof.

            (b) 'Excess Cash' means the amount by which the Estimated Blocker
      Price exceeds the Final Blocker Price.

            (c) 'Final Blocker Price' means the final purchase price (determined
      after all adjustments made pursuant to Section 2.4(d) of the InterLink
      Agreement and assuming that all purchase price holdbacks and payments into
      escrow have been paid by Vulcan to the shareholders of the Blocker
      Corporations) paid by Vulcan to the shareholders of the Blocker
      Corporations.

            (d) 'InterLink Agreement' means that certain Purchase and Sale
      Agreement, among Charter Investment, Inc. (formerly Charter
      Communications, Inc.), InterLink and the "Sellers" listed on the signature
      pages thereto, dated as of April 26, 1999, as amended.

            (e) 'Second Closing Cash Amount' means the amount by which Eight
      Hundred Twenty-Five Million ($825,000,000) exceeds the
      Estimated Blocker Price.

      2. Section 2 of the Purchase Agreement is hereby amended and restated in
its entirety as follows:

            "2.  Closing; Deliveries.

                  (a) First Closing. The closing of the purchase and sale of the
First Issuance Acquired Membership Interests (the 'FIRST CLOSING') shall occur
at the offices of Irell & Manella LLP ('I&M'), 1800 Avenue of the Stars, Suite
900, Los Angeles, California 90067, on a date on or before August 10, 1999, to
be agreed upon by the Company and Buyer. At the First Closing, the Company shall
deliver to Buyer or his designee one or more certificates evidencing the First
Issuance Acquired Membership Interests registered in the name of Buyer or his


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designee and Buyer shall pay or cause to be paid to the Company the purchase
price for the First Issuance Acquired Membership Interests by check or wire
transfer. The date on which the First Closing occurs is hereinafter referred to
as the 'FIRST CLOSING DATE.'

                  (b) Second Closing. The closing of the purchase and sale of
the Second Issuance Acquired Membership Interests (the 'SECOND CLOSING') shall
occur at the offices of I&M on a date after August 10, 1999 and on or before
September 1, 1999 to be agreed upon by the Company and Buyer. At the Second
Closing, the Company shall deliver to Buyer or his designee one or more
certificates evidencing the Second Issuance Acquired Membership Interests
registered in the name of Buyer or his designee and Buyer shall pay or cause to
be paid to the Company the purchase price for the Second Issuance Acquired
Membership Interests by check or wire transfer. The date on which the Second
Closing occurs is hereinafter referred to as the 'SECOND CLOSING DATE.'

                  (c) Third Closing. The closing of the sale of the Third
Issuance Acquired Membership Interest (the 'THIRD CLOSING') shall occur at the
office of I&M within five days (or sooner if agreed to between Buyer and the
Company) after the date on which Vulcan acquires the interests in InterLink (the
"InterLink Interest") owned by the Blocker Corporations. At the Third Closing,
the Company shall deliver to Vulcan, as Buyer's designee, one or more
certificates evidencing the Third Issuance Acquired Membership Interests
registered in the name of Vulcan or such other person or entity as may be
designated by Allen and Vulcan (or such other person or entity designated by
Buyer) shall contribute to the Company the InterLink Interest. From and after
the Third Closing, Vulcan shall have no further obligation under the InterLink
Agreement other than for payment of the Final Blocker Price and shall have no
right to any indemnification or other payment that might otherwise be payable to
it under the InterLink Agreement.

            (d) Total Amount to Company. The parties intend that the sum of the
following will valued at One Billion Three Hundred Twenty-Five Million Dollars
($1,325,000,000): (i) the purchase price paid at the First Closing, (ii) the
purchase price paid at the Second Closing, (iii) the InterLink Interest, and
(iv) the Excess Cash, if any.

            (e) Contribution of InterLink Interest. Immediately after Vulcan's
contribution of the InterLink Interest to the Company, the Company shall
contribute the InterLink Interest to Charter Communications Holdings, LLC, its
wholly-owned subsidiary ('CCH'). Immediately after the contribution of the
InterLink Interest to CCH, CCH shall contribute the InterLink Interest to
Charter Communications Operating, LLC, its wholly-owned subsidiary ('CCO')."

      3. Except as otherwise set forth in this Amendment, the Purchase Agreement
remains unchanged and in full force and effect.

      4. This Amendment may be executed in any number of counterparts, each of
which will be deemed an original, but all of which together will constitute one
and the same instrument.


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                            [SIGNATURE PAGE FOLLOWS]


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IN WITNESS WHEREOF, Company and the Buyer have caused this Amendment to be
signed by their duly authorized representatives, all as of the date first
written above.




                                    CHARTER COMMUNICATIONS HOLDING
                                    COMPANY, LLC, a Delaware limited
                                    liability company

                                        /s/ Curtis S. Shaw
                                    By:_____________________________________
                                       Name:  Curtis S. Shaw
                                       Its:   Senior Vice President, General
                                              Counsel and Secretary

                                    CHARTER COMMUNICATIONS HOLDINGS, LLC,
                                    a Delaware limited liability company

                                        /s/ Curtis S. Shaw
                                    By:_____________________________________
                                       Name:  Curtis S. Shaw
                                       Its:   Senior Vice President, General
                                              Counsel and Secretary

                                    CHARTER COMMUNICATIONS OPERATING,
                                    LLC, a Delaware limited liability
                                    company

                                        /s/ Curtis S. Shaw
                                    By:_____________________________________
                                       Name:  Curtis S. Shaw
                                       Its:   Senior Vice President, General
                                              Counsel and Secretary









                     [SIGNATURES CONTINUE ON FOLLOWING PAGE]


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                          [SIGNATURE PAGE TO AMENDMENT]


                                    BUYER


                                     /s/ Paul G. Allen
                                    -------------------------------------
                                    Paul G. Allen


                                    VULCAN CABLE III INC., a Washington
                                    corporation


                                    By: /s/ William D. Savoy
                                       ----------------------------------
                                       Name: William D. Savoy
                                       Its:  President


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