<PAGE>
                                                                    EXHIBIT 4.3
                            SUPPLEMENTAL INDENTURE

     SUPPLEMENTAL INDENTURE dated as of May 15, 2001, between TV Guide, Inc., a
Delaware corporation (the "Company"), on behalf of itself and each subsidiary
listed that is a Subsidiary Guarantor under the Original Indenture (as defined
below), and The Bank of New York, a New York banking corporation, as trustee
(the "Trustee").

                             W I T N E S S E T H

     WHEREAS, the Company and certain Subsidiary Guarantors have heretofore
executed and delivered to the Trustee an indenture (as supplemented by
supplemental indentures dated as of June 29, 1999, May 5, 2000 and April 6,
2001, the "Original Indenture") dated as of March 1, 1999;

     WHEREAS, the Company is a wholly-owned subsidiary of Gemstar-TV Guide
International, Inc., a Delaware corporation ("Parent");

     WHEREAS, Section 9.02 of the Original Indenture provides, among other
things, that, with the written consent of the Holders of not less than a
majority in aggregate principal amount of the Securities then outstanding, the
Company and the Trustee may amend the Original Indenture, except as provided
therein;

     WHEREAS, the 8% Senior Subordinated Notes due 2009 (the "Notes") constitute
the only Securities outstanding under the Original Indenture;

     WHEREAS, the Company desires to amend or delete certain provisions to the
Original Indenture;

     WHEREAS, all action on the part of the Company necessary to authorize its
execution, delivery and performance of the Original Indenture, as further
supplemented by this Supplemental Indenture, has been duly taken;

     WHEREAS, the Company has solicited the consent (the "Consent Solicitation")
of the Holders of the Notes to amendments (the "Amendments") to certain
provisions of the Indenture pursuant to that certain consent solicitation
statement dated May 14, 2001 (the "Consent Solicitation Statement");

     WHEREAS, Holders of at least a majority in aggregate principal amount of
the Notes have consented in writing to the Amendments; and

     WHEREAS, the Company and the Subsidiary Guarantors desire to execute and
deliver, and have requested the Trustee to join in the execution and delivery
of, this Supplemental Indenture for the purpose of amending certain provisions
of the Original Indenture.

     NOW THEREFORE, in consideration of the premises and for other good and
valuable consideration, it is mutually covenanted and agreed for the equal and
ratable benefit of all Holders of the Securities as follows:

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                                  ARTICLE ONE

                                   DEFINITION
                                   ----------

     Section 1.1 Definitions. When used herein, "Tender Offer Completion Event"
shall mean such time as each of the following events shall have occurred: (i)
Parent shall have completed a tender offer in accordance with the terms and
conditions set forth in the Consent Solicitation Statement and (ii) each holder
of Notes that has tendered Notes pursuant to the tender offer shall have
received the Purchase Price in exchange therefor as provided in the Consent
Solicitation Statement. All other capitalized terms used but not defined herein
shall have the same meanings as in the Original Indenture.

                                  ARTICLE TWO

                        AMENDMENTS TO ORIGINAL INDENTURE
                        --------------------------------

     Section 2.1 Deleted Definitions. Upon the occurrence of the Tender Offer
Completion Event, Sections 1.01 and 1.02 of the Original Indenture shall be
amended by deleting the definition of each term that is used in the Original
Indenture only in the Sections or subsections thereof that are deleted pursuant
to Section 2.2. hereof; provided, that, all definitions and cross-references
contained in Sections 4.06 and 4.10 of the Original Indenture shall be construed
in accordance with the meanings ascribed thereto under the Original Indenture as
in effect immediately prior to the date hereof (giving effect, however, to
events that have occurred on or subsequent to the date hereof).

     Section 2.2 Deleted Provisions. Upon the occurrence of the Tender Offer
Completion Event, the text of each of the following Articles, Sections,
subsections or clauses of the Original Indenture shall be deleted in its
entirety and replaced, in each case, by the words "Intentionally Omitted":

"Section 4.02. SEC Reports";

"Section 4.03. Limitation on Debt";

"Section 4.04. Limitation on Restricted Payments";

"Section 4.05. Limitation on Liens";

"Section 4.07. Limitation on Restrictions on Distributions from Restricted
               Subsidiaries";

"Section 4.08. Limitation on Transactions with Affiliates";

"Section 4.09. Limitation on Layered Debt";

"Section 4.12. Future Subsidiary Guarantors";

"Section 4.13. Maintenance of Non-Investment Company Status";

"Article V Surviving Company"; and

"Clauses (3), (4), (5), (6) and (8) of Section 8.02".


                                       2.

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     Section 2.3 Section 4.02 of the Original Indenture. Effective immediately
upon execution and delivery of this Supplemental Indenture by the parties
hereto, the following text shall be added to the end of Section 4.02 of the
Original Indenture:

     "Notwithstanding the foregoing, during the forty-five day period beginning
on May [insert fifth day prior to receipt of Requisite Consents], 2001, the
Company shall not be subject to the provisions of this Section 4.02. If the
Tender Offer Completion Event has not occurred by the end of such forty five-day
period, the Company shall, as soon as practicable thereafter, make such filings
and provide such information and documentation as would have been required under
Section 4.02 during such forty five-day period had the Company been subject
thereto during such forty five-day period."

     Section 2.4 Section 4.14 of the Original Indenture. Effective immediately
upon execution and delivery of this Supplemental Indenture by the parties
hereto, the text of Section 4.14 of the Original Indenture shall be deleted in
its entirety and replaced with the following text:

     "The Company and the Subsidiary Guarantors shall comply with TIA Section
314(a)(4)."

                                 ARTICLE THREE

                            MISCELLANEOUS PROVISIONS
                            ------------------------

     Section 3.1 Ratification of Indenture; Supplemental Indenture Part of
Indenture. Except as expressly amended hereby, the Indenture is in all respects
ratified and confirmed and all the terms, conditions and provisions thereof
shall remain in full force and effect. This Supplemental Indenture shall form a
part of the Indenture for all purposes, and every holder of Securities
heretofore or hereafter authenticated and delivered shall be bound hereby.

     Section 3.2 Governing Law. THIS SUPPLEMENTAL INDENTURE SHALL BE GOVERNED
BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK BUT
WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT
THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED
THEREBY.

     Section 3.3 Trustee Makes No Representation. The Trustee makes no
representation as to the validity or sufficiency of this Supplemental Indenture.

     Section 3.4 Counterparts. The parties may sign any number of copies of this
Supplemental Indenture. Each signed copy shall be an original, but all of them
together represent the same agreement.

     Section 3.5 Effect of Headings. The Section headings herein are for
convenience only and shall not effect the construction thereof.


                                       3.

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     IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed as of the date first written above.



                          TV GUIDE, INC., on behalf of itself and the Subsidiary
                          Guarantors


                          By:  /s/  Peter C. Boylan, III
                              -----------------------------
                              Peter C. Boylan, III
                              Co-Chairman & Chief Executive Officer, and Co-
                                President


                          THE BANK OF NEW YORK


                          By:  /s/  Van K. Brown
                              -----------------------------
                              Name:  Van K. Brown
                              Title: Vice President




                                       4.