Document:

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                                                                     EXHIBIT 4.6

                               AMENDMENT NO. 1 TO
                            INVESTOR RIGHTS AGREEMENT

                  THIS AMENDMENT NO. 1 TO INVESTOR RIGHTS AGREEMENT (this
"Amendment") is made as of August 12, 2002, by and among Ziff Davis Holdings
Inc., a Delaware corporation (the "Company"), and Willis Stein & Partners III,
L.P., a Delaware limited partnership ("Willis Stein III"), and Willis Stein &
Partners II, L.P., a Delaware limited partnership ("Willis Stein II" and
together with Willis Stein III, "Willis Stein"). Unless otherwise indicated,
capitalized terms not defined herein shall have the meanings assigned to such
terms in the Investor Rights Agreement of the Company, dated as of April 5, 2000
(the "Pre-Amendment Investor Rights Agreement").

                  WHEREAS, Willis Stein and the Company may amend the
Pre-Amendment Investor Rights Agreement pursuant to Section 17B thereof.

                  WHEREAS, Willis Stein and the Company desire to amend the
Pre-Amendment Investor Rights Agreement on the terms set forth herein.

                  NOW, THEREFORE, in consideration of the mutual agreements and
covenants made herein and for other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the parties hereto, intending
to be legally bound, hereby agree as follows:

                  1. Amendment of the Pre-Amendment Investor Rights Agreement.

              (a) The definition of "Preferred Stock" in Section 16 of the
Pre-Amendment Investor Rights Agreement is hereby deleted in its entirety and
replaced with the following:

                  "`Preferred Stock' means the Company's Series A Preferred
                  Stock, par value $.01 per share, Series B Preferred Stock, par
                  value $.01 per share, Series C Convertible Preferred Stock,
                  par value $.01 per share, Series D Redeemable Preferred Stock,
                  par value $.01 per share, Series E Preferred Stock, par value
                  $.01 per share, Series E-1 Preferred Stock, par value $.01 per
                  share, and any other series or classes of Preferred Stock
                  issued by the Company."

              (b) Section 4A of the Pre-Amendment Investor Rights Agreement is
hereby amended by inserting the following sentence at the end of Section 4A of
the Pre-Amendment Investor Rights Agreement:

                  "Notwithstanding the foregoing, the percentage of New
                  Securities that is required to be offered to each holder of
                  Investor Shares pursuant to this Section 4A will exclude, when
                  calculating such percentage, the aggregate amount of such New
                  Securities that were purchased or will be purchased by the
                  holder or holders of (i) Series E Preferred Stock pursuant to
                  the purchase rights granted to all holders of Series E
                  Preferred Stock pursuant

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                  to Article Four B.V.7(a) of the Fifth Amended and Restated
                  Certificate of Incorporation of the Company and (ii) Series
                  E-1 Preferred Stock pursuant to the purchase rights granted to
                  all holders of Series E-1 Preferred Stock pursuant to Article
                  Four B.VI.7(a) of the Fifth Amended and Restated Certificate
                  of Incorporation of the Company."

              (c) The definition of "Liquidation Value" in Section 16 of the
Pre-Amendment Investor Rights Agreement is hereby deleted in its entirety and
replaced with the following:

                  "`Liquidation Value'" means, with respect to each share of
                  Preferred Stock, the liquidation value of such share of
                  Preferred Stock as set forth in the Company's Certificate of
                  Incorporation, plus the aggregate amount of accrued and unpaid
                  dividends thereon."

                  2. Effectiveness. Pursuant to Section 17B of the Pre-Amendment
Investor Rights Agreement, this Amendment shall be effective and binding upon
execution hereof by the Company and Willis Stein, and the Pre-Amendment Investor
Rights Agreement shall be deemed amended as of the date first written above
immediately following such execution by the Company and Willis Stein. Any
reference in the Pre-Amendment Investor Rights Agreement to "Agreement" shall
hereafter be deemed to refer to the Pre-Amendment Investor Rights Agreement as
hereby amended.

                  3. Miscellaneous.

              (a) Counterparts. This Amendment may be executed in any number of
counterparts, any one of which need not contain the signatures of more than one
party, but all of such counterparts shall constitute one amendment.

              (b) Governing Law. The corporate law of Delaware will govern all
issues arising under, or in connection with, this Amendment concerning the
relative rights of the Company and its Stockholders. All other issues arising
under, or in connection with, this Amendment shall be governed by and construed
in accordance with the laws of the State of Illinois without giving effect to
any choice of law or conflict of law provision or rule (whether of the State of
Illinois or any other jurisdiction) that would cause the application of the law
of any jurisdiction other than the State of Illinois.

              (c) Effect on Pre-Amendment Investor Rights Agreement. Except as
expressly modified by this Amendment, the Pre-Amendment Investor Rights
Agreement remains in full force and effect.

                            *   *   *   *   *

                                      -2-

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                  IN WITNESS WHEREOF, the parties hereto have executed this
Amendment No. 1 to Investor Rights Agreement on the day and year first above
written.

                             THE COMPANY:

                             ZIFF DAVIS HOLDINGS INC.

                             By:    /s/ Bart W. Catalane
                                    --------------------
                             Its:   Chief Operating Officer and
                                    Chief Financial Officer

                             WILLIS STEIN & PARTNERS III, L.P.:

                             By:  Willis Stein & Partners Management III, L.P.
                             Its: General Partner

                             By:  Willis Stein & Partners Management III, L.L.C.
                             Its: General Partner

                             By:    /s/ Daniel H. Blumenthal
                                    ------------------------
                             Name:  Daniel H. Blumenthal
                             Title: Managing Director

                             WILLIS STEIN & PARTNERS II, L.P.:

                             By:  Willis Stein & Partners Management II, L.P.
                             Its: General Partner

                             By:  Willis Stein & Partners Management II, L.L.C.
                             Its: General Partner

                             By:    /s/ Daniel H. Blumenthal
                                    ------------------------
                             Name:  Daniel H. Blumenthal
                             Title: Member<PAGE>

                                                                     EXHIBIT 4.7

                             SUPPLEMENTAL INDENTURE

         This Supplemental Indenture (this "Supplemental Indenture"), dated as
of September 18, 2002, by and among Ziff Davis Media Inc., a Delaware
corporation (the "Company") Ziff Davis Holdings Inc., a Delaware corporation and
indirect parent of the Company, Ziff Davis Intermediate Holdings Inc., a
Delaware corporation and direct parent of the Company (collectively with Ziff
Davis Holdings Inc., the "Guaranteeing Parties"), the other Guarantors (as
defined in the Indenture referred to herein) and Deutsche Bank Trust Company
Americas, as trustee under the indenture referred to below (the "Trustee").

                              W I T N E S S E T H:

         WHEREAS, the Company has heretofore executed and delivered to the
Trustee an indenture (the "Indenture"), dated as of August 12, 2002, providing
for the initial issuance of an aggregate principal amount of up to $90.3 million
of Senior Subordinated Compounding Notes due 2009 (the "Notes");

         WHEREAS, the Indenture provides that under certain circumstances the
Guaranteeing Parties shall execute and deliver to the Trustee a supplemental
indenture pursuant to which the Guaranteeing Parties shall unconditionally
guarantee all of the Company's Obligations under the Notes and the Indenture on
the terms and conditions set forth herein (the "Guarantee"); and

         WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

         NOW THEREFORE, in consideration of the foregoing and for other good and
valuable consideration, the receipt of which is hereby acknowledged, the
Guaranteeing Parties and the Trustee mutually covenant and agree for the equal
and ratable benefit of the Holders of the Notes as follows:

1.       Capitalized Terms. Capitalized terms used herein without definition
         -----------------
         shall have the meanings assigned to them in the Indenture.

2.       Agreement to Guarantee. The Guaranteeing Parties hereby agree as
         ----------------------
         follows:

               (i)  Along with all Guarantors named in the Indenture, to jointly
                    and severally Guarantee to each Holder of a Note
                    authenticated and delivered by the Trustee and to the
                    Trustee and its successors and assigns, irrespective of the
                    validity and enforceability of the Indenture, the Notes or
                    the obligations of the Company hereunder or thereunder,
                    that:

                    (A)  the principal of and interest on the Notes will be
                         promptly paid in full when due, whether at maturity, by
                         acceleration, redemption or otherwise, and interest on
                         the overdue principal of and interest on the Notes, if
                         any, if lawful, and all other obligations of the
                         Company to the Holders or the Trustee hereunder or
                         thereunder

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                         will be promptly paid in full or performed, all in
                         accordance with the terms hereof and thereof; and

                    (B)  in case of any extension of time of payment or renewal
                         of any Notes or any of such other obligations, that
                         same will be promptly paid in full when due or
                         performed in accordance with the terms of the extension
                         or renewal, whether at stated maturity, by acceleration
                         or otherwise. Failing payment when due of any amount so
                         guaranteed or any performance so guaranteed for
                         whatever reason, the Guarantors shall be jointly and
                         severally obligated to pay the same immediately.

               (ii) The obligations hereunder shall be unconditional,
                    irrespective of the validity, regularity or enforceability
                    of the Notes or the Indenture, the absence of any action to
                    enforce the same, any waiver or consent by any Holder of the
                    Notes with respect to any provisions hereof or thereof, the
                    recovery of any judgment against the Company, any action to
                    enforce the same or any other circumstance which might
                    otherwise constitute a legal or equitable discharge or
                    defense of a guarantor.

              (iii) The following is hereby waived: diligence, presentment,
                    demand of payment, filing of claims with a court in the
                    event of insolvency or bankruptcy of the Company, any right
                    to require a proceeding first against the Company, protest,
                    notice and all demands whatsoever.

               (iv) This Guarantee shall not be discharged except by complete
                    performance of the obligations contained in the Notes and
                    the Indenture or pursuant to Section 6 hereof.

               (v)  If any Holder or the Trustee is required by any court or
                    otherwise to return to the Company, the Guarantors, or any
                    custodian, Trustee, liquidator or other similar official
                    acting in relation to either the Company or the Guarantors,
                    any amount paid by either to the Trustee or such Holder,
                    this Guarantee, to the extent theretofore discharged, shall
                    be reinstated in full force and effect.

               (vi) The Guaranteeing Parties shall not be entitled to any right
                    of subrogation in relation to the Holders in respect of any
                    obligations guaranteed hereby until payment in full of all
                    obligations guaranteed hereby.

              (vii) As between the Guarantors, on the one hand, and the Holders
                    and the Trustee, on the other hand, (x) the maturity of the
                    obligations guaranteed hereby may be accelerated as provided
                    in Article 6 of the Indenture for the purposes of this
                    Guarantee, notwithstanding any stay, injunction or other
                    prohibition preventing such acceleration in respect of the
                    obligations guaranteed hereby, and (y) in the event of any
                    declaration of acceleration of such obligations as provided
                    in Article 6 of the Indenture, such

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                    obligations (whether or not due and payable) shall forthwith
                    become due and payable by the Guarantors for the purpose of
                    this Guarantee.

             (viii) The Guarantors shall have the right to seek contribution
                    from any non-paying Guarantor so long as the exercise of
                    such right does not impair the rights of the Holders under
                    the Guarantee. (i) Pursuant to Section 11.03 of the
                    Indenture, after giving effect to any maximum amount and any
                    other contingent and fixed liabilities that are relevant
                    under any applicable Bankruptcy or fraudulent conveyance
                    laws (including, without limitation, all Senior Indebtedness
                    of such Guarantor), and after giving effect to any
                    collections from, rights to receive contribution from or
                    payments made by or on behalf of any other Guarantor in
                    respect of the obligations of such other Guarantor under
                    Article 11 of the Indenture shall result in the obligations
                    of such Guarantor under its Guarantee not constituting a
                    fraudulent transfer or conveyance.

3.       Subordination. The Obligations of the Guaranteeing Parties under its
         -------------
         Guarantee pursuant to this Supplemental Indenture shall be junior and
         subordinated to the Senior Indebtedness of the Guaranteeing Parties on
         the same basis as the Notes are junior and subordinated to the Senior
         Indebtedness of the Company. For the purposes of the foregoing
         sentence, the Trustee and the Holders shall have the right to receive
         and/or retain payments by the Guaranteeing Parties only at such time as
         they may receive and/or retain payments in respect of the Notes
         pursuant to the Indenture, including Article 10 thereof.

4.       Execution and Delivery. Each Guaranteeing Party agrees that the
         ----------------------
         Guarantees shall remain in full force and effect notwithstanding any
         failure to endorse on each Note a notation of such Guarantee.

5.       Guaranteeing Parties May Consolidate, Etc. on Certain Terms.
         -----------------------------------------------------------

               (i)  The Guaranteeing Parties may not consolidate with or merge
                    with or into (whether or not such Guarantor is the surviving
                    Person) another corporation, Person or entity whether or not
                    affiliated with such Guarantor unless:

                    (A)  subject to Section 11.05 of the Indenture, the Person
                         formed by or surviving any such consolidation or merger
                         (if other than a Guarantor or the Company) shall be a
                         corporation organized and validly existing under the
                         laws of the United States or any state thereof or the
                         District of Columbia, and unconditionally assumes all
                         the obligations of such Guarantor, pursuant to a
                         supplemental indenture in form and substance reasonably
                         satisfactory to the Trustee, under the Notes, the
                         Indenture and the Guarantee on the terms set forth
                         herein or therein;

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                    (B)  immediately after giving effect to such transaction, no
                         Default or Event of Default exists; and

                    (C)  the company would be permitted, immediately after
                         giving effect to such transaction, to incur at least
                         $1.00 of additional Indebtedness (other than Permitted
                         Indebtedness) pursuant to Section 4.09 of the
                         Indenture.

               (ii) In case of any such consolidation, merger, sale or
                    conveyance and upon the assumption by the successor Person,
                    by supplemental indenture, executed and delivered to the
                    Trustee and satisfactory in form to the Trustee, of the
                    Guarantee endorsed upon the Notes and the due and punctual
                    performance of all of the covenants and conditions of the
                    Indenture to be performed by the Guarantor, such successor
                    Person shall succeed to and be substituted for the Guarantor
                    with the same effect as if it had been named herein as a
                    Guarantor. Such successor Person thereupon may cause to be
                    signed any or all of the Guarantees to be endorsed upon all
                    of the Notes issuable hereunder which theretofore shall not
                    have been signed by the Company and delivered to the
                    Trustee. All the Guarantees so issued shall in all respects
                    have the same legal rank and benefit under the Indenture as
                    the Guarantees theretofore and thereafter issued in
                    accordance with the terms of the Indenture as though all of
                    such Guarantees had been issued at the date of the execution
                    hereof.

              (iii) Except as set forth in Articles 4 and 5 of the Indenture,
                    and notwithstanding clauses(i)(C) above, nothing contained
                    in the Indenture or in any of the Notes shall prevent any
                    consolidation or merger of a Guarantor with or into the
                    Company or another Guarantor, or shall prevent any sale or
                    conveyance of the property of a Guarantor as an entirety or
                    substantially as an entirety to the Company or another
                    Guarantor.

6.       Releases. In the event of a sale or other disposition of all of the
         --------
         assets of any Guarantor, by way of merger, consolidation or otherwise,
         or a sale or other disposition of all of the capital stock of any
         Guarantor, then such Guarantor (in the event of a sale or other
         disposition, by way of merger, consolidation or otherwise, of all of
         the capital stock of such Guarantor) or the corporation acquiring the
         property (in the event of a sale or other disposition of all or
         substantially all of the assets of such Guarantor) will be released and
         relieved of any obligations under its Guarantee; provided that the Net
                                                          --------
         Proceeds of such sale or other disposition are applied in accordance
         with the applicable provisions of the Indenture, including without
         limitation Section 4.10 of the Indenture. Upon delivery by the Company
         to the Trustee of an Officers' Certificate and an Opinion of Counsel
         to the effect that such sale or other disposition was made by the
         Company in accordance with the applicable provisions of the Indenture,
         including without limitation Section 4.10 of the Indenture, the
         Trustee shall execute any documents reasonably required in order to
         evidence the release of any Guarantor from its obligations under its
         Guarantee.

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                  Any Guarantor not released from its obligations under its
Guarantee shall remain liable for the full amount of principal of and interest
on the Notes and for the other obligations of any Guarantor under the Indenture
as provided in Article 11 of the Indenture.

7.       No Recourse Against Others. No past, present or future director,
         --------------------------
         officer, employee, incorporator, stockholder or agent of any
         Guaranteeing Party, as such, shall have any liability for any
         obligations of the Company or any Guaranteeing Party under the Notes,
         any Guarantees, the Indenture or this Supplemental Indenture or for any
         claim based on, in respect of, or by reason of, such obligations or
         their creation. Each Holder of the Notes by accepting a Note waives and
         releases all such liability. The waiver and release are part of the
         consideration for issuance of the Notes. Such waiver may not be
         effective to waive liabilities under the federal securities laws and it
         is the view of the SEC that such a waiver is against public policy.

8.       New York Law to Govern. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL
         ----------------------
         GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE 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.

9.       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.

10.      Effect of Headings. The Section headings herein are for convenience
         ------------------
         only and shall not affect the construction hereof.

11.      The Trustee. The Trustee shall not be responsible in any manner
         -----------
         whatsoever for or in respect of the validity or sufficiency of this
         Supplemental Indenture or for or in respect of the recitals contained
         herein, all of which recitals are made solely by the Guaranteeing
         Parties and the Company.

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

Dated: September 18, 2002
                                       Ziff Davis Holdings Inc.

                                       By:      /s/ Bart W. Catalane
                                                ------------------------------
                                                Name:  Bart W. Catalane
                                                Title: Chief Operating Officer

                                       Ziff Davis Intermediate Holdings Inc.

                                       By:      /s/ Bart W. Catalane
                                                ------------------------------
                                                Name:  Bart W. Catalane
                                                Title: Vice President

                                       Deutsche Bank Trust Company Americas, as
                                       Trustee

                                       By:      /s/ Irina Golovashchuk
                                                ------------------------------
                                                Name:  Irina Golovashchuk
                                                Title: Authorized Signatory

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