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                                                                    EXHIBIT 4.10
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                               HISTORIC TW INC.,
                    TIME WARNER ENTERTAINMENT COMPANY, L.P.,
                          WARNER COMMUNICATIONS INC.,
                     AMERICAN TELEVISION AND COMMUNICATIONS
                                CORPORATION, AND
                             TIME WARNER CABLE INC.



                                       TO

                             THE BANK OF NEW YORK,

                                                                        TRUSTEE,

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                         Eighth Supplemental Indenture

                          Dated as of December 9, 2003

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         EIGHTH SUPPLEMENTAL INDENTURE dated as of December 9, 2003 among
HISTORIC TW INC. (f/k/a "Time Warner Inc."), a corporation duly organized and
existing under the laws of the State of Delaware ("HTW"), TIME WARNER
ENTERTAINMENT COMPANY, L.P., a Delaware limited partnership ("TWE"), TIME WARNER
CABLE INC., a corporation duly organized and existing under the laws of the
State of Delaware, each of the other partners of TWE signatories hereto (the "TW
Partners"), and THE BANK OF NEW YORK, a banking corporation duly organized and
existing under the laws of New York, as Trustee (the "Trustee").

                                    RECITALS

         HTW, TWE, the TW Partners and the Trustee have executed and delivered
an Indenture dated as of April 30, 1992, as amended by the First Supplemental
Indenture dated as of June 30, 1992, the Second Supplemental Indenture dated as
of December 9, 1992, the Third Supplemental Indenture dated as of October 12,
1993, the Fourth Supplemental Indenture dated as of March 29, 1994, the Fifth
Supplemental Indenture dated as of December 28, 1994, the Sixth Supplemental
Indenture dated as of September 29, 1997, and the Seventh Supplemental Indenture
dated as of December 29, 1997 (the "Indenture"), providing for the issuance from
time to time of unsecured debentures, notes or other evidences of indebtedness
(the "Securities"), to be issued in one or more series as provided in the
Indenture and the guaranties of the Securities by the TW Partners (the "TW
Partner Guaranties").

         HTW, TWE, TWC and each of the TW Partners have duly authorized the
execution and delivery of this Eighth Supplemental Indenture to provide for the
guaranty of the TW Partner Guaranties by TWC (the "TWC Guaranty") and the
addition of TWC as a party to the Indenture, subject in each case to the terms
and conditions described herein.

         This Eighth Supplemental Indenture is being executed pursuant to and in
accordance with Section 901 of the Indenture.

         All things necessary to make this Eighth Supplemental Indenture a valid
and binding agreement of HTW, TWE, TWC and the TW Partners have been done.

         NOW, THEREFORE, WITNESSETH:

         For and in consideration of the premises and other good and valuable
consideration, the sufficiency and receipt of which are hereby acknowledged, and
the purchase of the Securities by the Holders thereof, it is mutually agreed,
for the equal and proportionate benefit of all Holders of the Securities, as
follows:

                                  ARTICLE ONE
                      INCORPORATION OF PREVIOUS DOCUMENTS

         SECTION 101. Incorporation of Previous Documents.

         This Eighth Supplemental Indenture is a supplemental indenture within
the meaning of the Indenture and shall be read together therewith, and shall
have the same effect as though all the provisions thereof and hereof were
contained in one instrument. Unless otherwise expressly provided, the provisions
of the Indenture are incorporated herein by reference.

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         SECTION 102. Definitions.

         Unless otherwise provided herein, the terms used herein shall have the
meanings ascribed to such terms in the Indenture.

         SECTION 103. Governing Law.

         This Eighth Supplemental Indenture, the Indenture and the Securities
shall be governed by and construed in accordance with the laws of the State of
New York.

                                  ARTICLE TWO
                                  TWC GUARANTY

         The TWC Guaranty provided for in this Article Two shall become
effective upon (i) execution and delivery of this Eighth Supplemental Indenture
by each of the parties hereto and (ii) the occurrence of the Effective Date
under, and as defined in, either or both of (x) the 5-year revolving Credit
Agreement, dated on or about December 9, 2003, among TWC, TWE, the lenders
party thereto, JPMorgan Chase Bank, as Administrative Agent, Citicorp North
America Inc. and Deutsche Bank AG, New York Branch, as Co-Syndication Agents,
and ABN Amro Bank, N.V. and BNP Paribas, as Co-Documentation Agents and (y) the
364-day revolving Credit Agreement, dated on or about December 9, 2003, among
TWC, TWE, the lenders party thereto, JPMorgan Chase Bank, as Administrative
Agent, Citicorp North America Inc. and Deutsche Bank AG, New York Branch, as
Co-Syndication Agents, and ABN Amro Bank, N.V. and BNP Paribas, as
Co-Documentation Agents, and shall terminate (and shall not under any
circumstances be required to be reinstated) upon the delivery to the Trustee by
TWE of an Officers' Certificate certifying that all conditions and/or
circumstances requiring the issuance of the TWC Guarantee under and pursuant to
the terms of the Indenture have been satisfied and/or no longer exist, and that
the TWC Guaranty is terminated, which Officers' Certificate may be delivered by
TWE in its sole discretion on any date after the effectiveness hereof on which
the conditions for its delivery so exist.

         For value received, TWC and, subject to the terms of the Indenture,
its successors and assigns, hereby fully and unconditionally guarantees to
each Holder of Securities Outstanding as of the date hereof and any Securities
heretofore issued and Outstanding which reference the applicability of this
Guaranty (collectively, the "Guaranteed Securities"), and to the Trustee on
behalf of each such Holder, the due and punctual payment of the obligations of
the TW Partners under the respective TW Partner Guaranties as described in the
Indenture and in the TW Partner Guaranties. In case of the failure of any TW
Partner or any successor thereto to satisfy its payment obligations, or any
other obligations, under its TW Partner Guaranty in accordance with the terms
thereof, TWC hereby agrees to immediately satisfy such payment or other
obligations.

         TWC hereby agrees that as long as this Article Two is in effect, its
obligations hereunder and under the Indenture shall be unconditional and
absolute, irrespective of the identity of TWE or any TW Partner, the validity,
regularity or enforceability of any of the TW Partner Guaranties, any such
Securities or the Indenture, the absence of any action to enforce the same, the
granting of any waiver or consent by the Holder of any such Securities with
respect to any provisions thereof or of such TW Partner Guaranties, the
recovery of any judgment against TWE

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or any TW Partner or any action to enforce the same, or any other circumstance
which might otherwise constitute a legal or equitable discharge or defense of
any TW Partner as a guarantor or of TWC as a guarantor of such TW Partner's
Guaranty. TWC hereby waives diligence, presentment, demand of payment, filing
of claims with a court in the event of insolvency or bankruptcy of TWE or of
any TW Partner, any right to require that a proceeding be brought first against
TWE or any TW Partner, protest, notice and all demands whatsoever, and
covenants that as long as this Article Two is in effect, this Guaranty will not
be discharged except by (i) complete discharge of the payment and other
obligations contained in the TW Partner Guaranties or in this Article Two or
(ii) as otherwise provided in the first paragraph of this Article Two.

         TWC acknowledges and agrees for the benefit of the Trustee and such
Holders that the Trustee and such Holders (in the case of an Event of Default
under Section 501(1) or (2) of the Indenture) may directly and simultaneously
proceed against TWC for the enforcement of this Guaranty, against TWE (as
Obligor) and against each of the TW Partners (under the TW Partner Guaranties
if they are then in effect). The obligations of TWC hereunder are independent
of the obligations of TWE under the Guaranteed Securities and the Indenture and
of the obligations of the TW Partners under the TW Partner Guarantees, and a
separate action or actions may be brought and prosecuted against TWC hereunder
whether or not (i) an action or proceeding is brought against TWE or any TW
Partner, (ii) TWE or any TW Partner is joined in any such action or proceeding
against TWC or (iii) the Trustee or such Holders have taken any action to
collect or attempted to otherwise collect such obligations from TWE or any TW
Partner or any other Person liable therefor.

         Anything in this Article Two to the contrary notwithstanding, this
Guaranty is and shall be deemed to be a Guaranty of payment, and not a Guaranty
of collection.

         If the Trustee or the Holder of any Guaranteed Security is required by
any court or otherwise to return to any TW Partner or any custodian, receiver,
liquidator, trustee, sequestrator or other similar official acting in relation
to such TW Partner, any amount paid to the Trustee or such Holder in respect of
such Guaranteed Security, this Guaranty, to the extent theretofore discharged,
shall be reinstated in full force and effect. TWC further agrees, to the
fullest extent that it may lawfully do so, that, as between itself, on the one
hand, and Holders of Guaranteed Securities and the Trustee, on the other hand,
the maturity of the obligations guaranteed hereby may be accelerated to the
extent provided in Article Five of the Indenture for purposes of this Guaranty,
notwithstanding any stay, injunction or other prohibition existing under any
applicable bankruptcy law preventing such acceleration in respect of the
obligations guaranteed hereby.

         No reference herein to the Indenture and no provision of this Article
Two or of the Indenture shall alter or impair this Guaranty, which is absolute
and unconditional, as to the payment of the obligations of each TW Partner
under its respective TW Partner Guaranties, except as provided in the first
paragraph of this Article Two.

                                 ARTICLE THREE
                  ADDITION OF TWC AS A PARTY TO THE INDENTURE

         By execution of this Eighth Supplemental Indenture, TWC agrees that it
shall be a party to, and shall be subject to, bound by and entitled to the
benefits of, the Indenture as supplemented by this Eighth Supplemental
Indenture until such time, if any, as the TWC
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Guaranty shall be terminated pursuant to Article Two hereof.

         This instrument may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute one and the same instrument.


                                    * * * *

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         IN WITNESS WHEREOF, the parties hereto have caused this Eighth
Supplemental Indenture to be duly executed by their respective officers or
agents, and their respective seals to be hereunto affixed and attested, all as
of the day and year first above written.

                                         HISTORIC TW INC.,



                                         by
                                                  s/ Raymond Murphy
                                              ---------------------------------
                                              Title: Vice President & Treasurer

                                         TIME WARNER ENTERTAINMENT
                                         COMPANY, L.P.,



                                         by
                                                  s/ Raymond Murphy
                                              ---------------------------------
                                              Title: V.P. & Asst. Treasurer

                                         WARNER COMMUNICATIONS INC.,



                                         by
                                                  s/ Raymond Murphy
                                              ---------------------------------
                                              Title: Vice President & Treasurer

                                         AMERICAN TELEVISION AND
                                         COMMUNICATIONS CORPORATION,



                                         by
                                                  s/ Raymond Murphy
                                              ---------------------------------
                                              Title: Vice President & Treasurer

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                                         TIME WARNER CABLE INC.,



                                         by
                                                  s/ Raymond Murphy
                                              ---------------------------------
                                              Title: V.P. & Asst. Treasurer

                                         THE BANK OF NEW YORK



                                         by
                                                  s/ Geovanni Barris
                                              ---------------------------------
                                              Title: Vice President