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                                                                   Exhibit 10.12


                               LICENSE AGREEMENT
                               -----------------

                              Dated April 5, 2000

     THIS LICENSE AGREEMENT (this "Agreement") is between ZD Inc. (hereinafter
"Licensor"), a Delaware corporation having offices at 28 East 28th Street, New
York, NY 10016 and Ziff Davis Publishing Holdings Inc. (hereinafter "Licensee"),
a Delaware corporation having offices at 227 West Monroe Street, Chicago, IL
60606.

     WHEREAS, as between Licensor and Licensee, Licensor is the owner of the
full right, title and interest in and to the mark ZD and the ZD logo illustrated
on Exhibit A attached hereto and made a part hereof (the "ZD Logo")
(hereinafter, collectively the "Marks").

     WHEREAS, ZD Inc. and ZD Holdings (Europe) Ltd. have entered into that
certain Purchase Agreement (the "Purchase Agreement"), dated as of December 6,
1999, with Ziff-Davis Media (formerly known as WS-ZD Acquisition, Inc.), whereby
Ziff Davis Media is acquiring certain assets and assuming certain liabilities,
all on the terms and subject to the conditions set forth in the Purchase
Agreement.

     WHEREAS, Licensee is entering into this Agreement with Licensor pursuant to
Section 6.1 of the Purchase Agreement as a wholly owned subsidiary of Ziff Davis
Media.

     WHEREAS, Licensee wishes to use the Marks in connection with printed
computer and technology periodicals (including magazines, newspapers and
newsletters) (hereinafter the "Publications") as an acronym for the house mark
"Ziff-Davis";

     WHEREAS, Licensor wishes to license Licensee to use the Marks on the
Publications on the terms and conditions hereof;

     In consideration of the mutual covenants and promises herein provided, the
parties agree as follows:

     1. Grant of License. Licensor hereby grants to Licensee, subject to the
        ----------------
terms and conditions of this Agreement, an exclusive, perpetual, irrevocable,
worldwide, non-transferable, royalty-free license to use the Marks during the
term of this Agreement in connection with the Publications, and on advertising
and promotional materials related to the Publications bearing the Marks. The
Marks may only be used on print materials and may not be used or appear in any
other medium, including, without limitation, television, the World Wide Web, the
Internet, or online, provided, however, the Marks may appear (x) in other media
if they are part of the cover or another page of a Publication that is displayed
in such other media and (y) in Alternative Electronic Versions (as defined in
Section 3(i)(z) of the Amended and Restated License Agreement between ZDNet and
ZD Publishing dated this same date (the "ZDNet License Agreement")), provided
that the Marks shall appear in that electronic version in locations
substantially equivalent to the locations that the Marks appear in that
Publication in print.  All
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rights not expressly granted herein are reserved to Licensor, including the
right to create derivative versions of the Marks and to use those derivative
marks (e.g., ZDU, ZDU logo, ZDTV, ZDTV logo) in all media but not in print
       ----
periodical magazines and newspapers. Notwithstanding any of the foregoing, (i)
Licensor shall have the right to use derivative versions of the Marks including
ZDNet for print newsletters, programming guides, advertisements, promotional
materials, books, course materials, materials which complement the use of those
derivative marks in other media and similar materials, (ii) during the period of
the ZDNet License Agreement, Licensor may use the mark ZDNet in print in
connection with Computer Shopper magazine (and its special editions, including
the Publication launched by Computer Shopper under the name eshopper (the name
of which shall be changed to a different name) and including changing the name
of Computer Shopper to ZDNet magazine) and (iii) after the fourth anniversary of
this date, Licensor may use the ZDNet mark without restrictions in print.
Licensor shall not use the mark ZD or the ZD Logo by themselves (i.e., without
                                                                 ----
some additional element) in any media.

     2. Value, Ownership and Use of the Marks; Quality Control.
        ------------------------------------------------------

          (a) Licensee acknowledges that great value is placed on the Marks and
the goodwill associated therewith and agrees not to challenge or contest
Licensor's ownership of the Marks anywhere in the world, or the validity of the
license granted under this Agreement. Nothing in this Agreement or in the
performance thereof, or that might otherwise be implied by law, shall operate to
grant Licensee any right, title or interest in or to the Marks other than as
specified in the license grant herein.

          (b) Licensee agrees to maintain the quality of all aspects of the
Publications (including any Alternative Electronic Versions) (e.g., editorial
content, production, advertising, etc.) at a level that is at least commensurate
with the quality of printed periodicals distributed by Licensor immediately
prior to the date of this Agreement. During the term of this Agreement, all use
of the Marks shall be in accordance with the guidelines attached hereto as
Exhibit A, as it may be reasonably amended by Licensor from time to time upon
notice to Licensee (the "Guidelines").

          (c) Licensee shall provide to Licensor use dates, use specimens and
other similar information relating to Licensee's use of the Marks as necessary
to maintain registration therefor, as and when reasonably requested by Licensor.
Licensee shall remedy any deficiencies in its use of the Marks and/or the
quality of the Publications (including any Alternative Electronic Versions) and
related advertising and promotional materials upon notice from Licensor.

          (d) Licensee shall use the Marks only in a form and manner that is
consistent with proper trademark usage and the Guidelines and only with the
symbols, notices and legends stated in Exhibit A as it may be reasonably amended
from time to time by Licensor upon notice to Licensee. Until the earlier of the
fourth anniversary of this date and the termination of the ZDNet License
Agreement, Licensee may at its option use the "ZD" mark in the form of the ZD
Logo; following that, Licensee shall, within six months following receipt of
Licensor's notice received on or after 42 months from the date of this
Agreement, cease all use of the ZD Logo and shall use the "ZD" mark only with
another logo which shall not be confusingly similar to the ZD Logo, it being
understood that both parties will use the letters "ZD."

                                      -2-
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          (e) Licensee understands, accepts and agrees that its usage of the
Marks shall inure solely to the benefit of Licensor. Licensee hereby assigns and
shall assign in the future to Licensor all rights it may acquire by operation of
law or otherwise in the Marks, including, without limitation, all applications
or registrations therefore, along with the goodwill associated therewith.

          (f) Licensee shall not knowingly do anything that is inconsistent
with or impairs the validity of the Marks, or that infringes, derogates, dilutes
or is inconsistent with or impairs the Marks or Licensor's ownership of the
Marks or which is detrimental to the reputation of the Marks or Licensor and
shall cooperate with and reasonably assist Licensor, if such cooperation and
assistance is requested, at Licensor's expense, in protecting and maintaining
Licensor's rights in the Marks, including, without limitation, in any efforts of
Licensor to register the Marks and/or record this Agreement. In the event that
Licensee unknowingly does anything that is inconsistent with or impairs the
validity of the Marks, or that infringes, derogates, dilutes or is inconsistent
with or impairs the Marks or Licensor's ownership of the Marks or which is
detrimental to the reputation of the Marks or Licensor, upon notice from
Licensor, Licensee shall promptly cease such activity.

          (g) Without limiting the generality of anything in this paragraph 2
or Exhibit A, Licensee specifically agrees that it shall not use the Marks, or
any name, mark or logo confusingly similar to either of the Marks, in any
corporate, business or trade name or in or on any electronic or online media,
product or service, whether now known or hereafter devised, except for the
Publications (including any Alternative Electronic Versions), and shall not file
any trademark applications or other indicia of ownership anywhere in the world
for either of the Marks or any confusingly similar name, mark or logo, or any
name, mark or logo incorporating either of the Marks.

          (h) Licensee shall not advertise, market or publicize the Publications
in a manner suggesting Licensor's sponsorship or endorsement of the
Publications, other than the use of the Marks as contemplated herein.

          (i) "Ziff" Mark.  Licensor agrees that it shall not use nor claim any
              -----------
rights in, whether arising from use, purchase or otherwise, the "Ziff" name,
including without limitation for trademarks, service marks, logos and domain
names.

     3. Sublicense. Licensee may sublicense the rights to use the Marks granted
        ----------
therein in connection with its license of foreign or other editions of one of
its Publications.  In the event of any such sublicense, the sublicensee shall be
bound by the terms and conditions of this Agreement and Licensee shall be liable
for any breach by the sublicensee of such terms and conditions.

     4. Infringement of the Marks; Prosecution and Maintenance of Marks.
        ---------------------------------------------------------------
          (a) Licensee shall notify Licensor in writing of any infringement or
imitations by others of the Marks which may come to Licensee's attention, and
Licensor shall have fifteen (15) business days to determine whether it shall
take action on account of any such infringements or imitations. Any action which
Licensor takes against a third party on account of any such infringement or
imitation shall be at Licensor's expense and any final award granted or any
settlement made shall be paid to Licensor, and Licensee shall have no claim to
such award or

                                      -3-
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settlement. In the event that Licensor does not take any action within such
fifteen (15) business day period, or if Licensor begins to take action against
such infringement or imitation but later abandons such action, Licensee may
institute any suit or take any action on account of any such suspected
infringements or imitations at its own expense and any final award shall be paid
to Licensee, provided, that (i) Licensee may not settle any litigation involving
the Marks in any way that limits the validity or rights of Licensor in the
Marks, without Licensor's prior written consent, and (ii) Licensee agrees to
indemnify and defend and hold harmless Licensor from all liability, damages,
loss, cost or expense (including but not limited to reasonable attorneys' fees
and expenses) arising from Licensee's institution of such suit or action. Each
party shall cooperate with the other party, at such other party's expense,
whenever a party takes any action against a suspected infringing or imitating
party.

          (b) Licensor, at its own expense, shall use reasonable efforts to
prosecute and maintain in full force and effect the registrations and
applications included among the Marks, except where Licensor shall notify
Licensee of a decision not to continue prosecution of any such application or
not to otherwise maintain any such Mark in force. In the event of such
notification, Licensee shall have the right to pursue or maintain any such
registration or application with Licensor's consent, which consent shall not be
unreasonably withheld, and, if Licensor so elects, such registration or
application shall be assigned to Licensor. Licensor and Licensee shall cooperate
with and assist each other in the provision of documents and information in
connection with any such registration or application as reasonably necessary to
effectuate the procurement and maintenance rights and obligations set forth in
this section.

     5. Term.
        ----

          (a) This Agreement shall commence on the date set forth above and
shall continue thereafter unless terminated in accordance with this Agreement
(the "Term").

          (b) In the event that Licensee ceases to use the Marks in connection
with the Publications for a period of more than 18 months, Licensor may request
by notice that the Licensee within the next 120 days use the Marks in ways
sufficient to avoid abandonment and supply Licensor with evidence of such use.
If Licensor fails to so use the Marks and provide such evidence of use within
such 120 days, Licensor shall have the right to use the Marks by themselves
(i.e., the ZD Marks and ZD Logo) on the World Wide Web, the Internet, or
 ----
online and, to the extent necessary to avoid abandonment, in print; provided,
however, that should Licensee resume use of the Marks in print, it shall notify
Licensor and Licensor shall promptly discontinue its use of the Marks in print.

          (c) Upon termination of this Agreement, whether pursuant to this
paragraph 5 or otherwise, Licensee shall cease and refrain from all use of the
Marks and any name, mark or design confusingly similar to either of the Marks.

          (d) In the event of a breach of this Agreement by either party, the
other party may pursue all available equitable and legal remedies (including
without limitation injunctive relief and monetary damages) but in no event shall
the license granted herein terminate because of either party's breach of its
obligations under this Agreement.

     6. Warranty and Indemnification. Licensee agrees to indemnify Licensor and
        ----------------------------
to save it harmless against all actions, claims, costs, damages or expenses
which may be brought or made against or incurred by Licensor as a result of or
in any way connected with (i) Licensee's

                                      -4-
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conduct of its business, (ii) the publication, marketing, promotion and
distribution of the Publications, including, without limitation, third-party
claims of libel, invasion of privacy or infringement of copyright based on
material published in the Publications, or (iii) Licensee's use of the Marks.
Licensee acknowledges that Licensor makes no representations or warranties to
Licensee with respect to the Marks and Licensee accepts the license granted
herein with such understanding. Licensor agrees to indemnify Licensee and to
save it harmless against all actions, claims, costs, damages or expenses which
may be brought or made against or incurred by Licensee as a result of or in any
way connected with the infringement of third party trademark rights as a result
of Licensor's use of its marks.

     7.  Limitation of Liability.  EXCEPT FOR ANY INDEMNIFICATION LIABILITY
         -----------------------
ARISING UNDER SECTION 6 HEREIN, UNDER NO CIRCUMSTANCES SHALL EITHER PARTY BE
LIABLE TO THE OTHER PARTY FOR INDIRECT, INCIDENTIAL, CONSEQUENTIAL, SPECIAL OR
EXEMPLARY DAMAGES (EVEN IF THAT PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGES), ARISING FROM ANY PROVISION OF THIS AGREEMENT (INCLUDING SUCH
DAMAGES INCURRED BY THIRD PARTIES), SUCH AS, BUT NOT LIMITED TO, LOSS OF REVENUE
OR ANTICIPATED PROFITS OR LOST BUSINESS.

     8.  No Public Statements.  Neither party may make any public statements or
         --------------------
disclosures concerning this Agreement or its terms to any medium except with the
prior approval of both parties or as required by law or the rules of any
applicable stock exchange or any governmental agency.

     9.  Notices.  Notices shall be in writing, sent either by hand, by
         -------
certified mail, return receipt requested, postage prepaid, or by Airborne or
other recognized overnight delivery service, all delivery changes prepaid and
addressed to Licensor and Licensee as follows:

  If to Licensor:     ZD Inc.
                      28 East 28th Street
                      New York, NY 10016
                      Attention: President
                                 General Counsel
                      Fax No.:   (212)503 3581

  If to Licensee:     Ziff Davis Publishing Holdings Inc.
                      c/o Willis Stein & Partners II, L.P.
                      227 West Monroe Street
                      Chicago, IL 60606
                      Attention: President
                                 General Counsel
                      Fax No.:   (312)422 2418

or to such other persons or addresses as the person to whom notice is given may
have previously furnished to the other in writing in the manner set forth above
(provided that notice of any

                                      -5-
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change of address shall be effective only upon receipt thereof). A notice shall
be deemed to have been delivered (i) upon receipt of such notice by the
receiving party in the event such notice is delivered by hand, (ii) three (3)
business days following the deposit of such notice in the mail if such notice is
being delivered by mail, and (iii) one business day following the deposit of
such notice with an overnight delivery service.

     10.  Governing Law.  This Agreement shall be governed by and construed in
          -------------
accordance with the laws of the State of New York, without regard to its choice
of law provisions.

     11.  Severability.  In the event that one or more provisions of this
          ------------
Agreement shall at any time be found to be invalid or otherwise rendered
unenforceable, such provision or provisions shall be severable from this
Agreement, so that the validity or enforceability of the remaining provisions of
this Agreement shall not be affected.

     12.  No Waiver.  Failure of the parties at any time to insist upon strict
          ---------
performance of any term, condition or covenant shall not be deemed a waiver of
its right at any time thereafter to insist on strict performance.

     13.  Entire Agreement. This Agreement expresses all the rights, duties and
          ----------------
obligations between the parties relating to its subject matter, and it may not
be modified or amended except in a writing signed by both parties.

     14.  No Agency.  This Agreement shall not be so construed as to constitute
          ---------
either party the agent or representative of the other for any purpose
whatsoever, and each party agrees that it has no authority to assume or to incur
any obligation or responsibility, expressed or implied, for, or on behalf of, or
in the name of, the other, or to bind, or attempt to bind, the other in any
manner or thing whatsoever.

     15.  Successors and Assigns.  This Agreement shall be deemed to inure
          ----------------------
to the benefit of and to bind the parties hereto and their respective
successors and permitted assigns.

     16.  Further Instruments.  Licensee agrees to execute such further
          --------------------
documents and take such further steps as may be reasonable requested by Licensor
to further the purposes of this Agreement.

     17.  Survival.  Paragraphs 2, 6, 7, 8, 9 and 11, and any other provisions
          --------
which by their terms or sense are intended to survive the expiration or
termination of this Agreement, shall survive the expiration or termination of
this Agreement.

     18.  Assignability.  Except as part of a merger or the sale of all or
          -------------
substantially all of the Publications, Licensee shall not assign or transfer
this agreement or its rights or obligations hereunder without the prior written
consent of the Licensor, which consent shall not be unreasonably withheld.

                                      -6-
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     IN WITNESS WHEREOF, the parties have caused this Agreement to be executed
on the date first written above.

                                             ZD INC.


                                             By: /s/ J. MALCOLM MORRIS
                                                ---------------------------
                                                Name:  J. Malcolm Morris
                                                Title: Senior Vice President



                                             ZIFF DAVIS PUBLISHING HOLDINGS INC.


                                             By: /s/ DANIEL H. BLUMENTHAL
                                                ---------------------------
                                                Name:  Daniel H. Blumenthal
                                                Title: President
<PAGE>

                                   EXHIBIT A
                              Trademark Guidelines


          All terms used in this Exhibit A that are defined in the Agreement
shall have the meaning ascribed to them in the Agreement.

     1.   The Marks licensed under the Agreement shall mean the "ZD" mark and
the "ZD" logo.  The Marks licensed under the Agreement shall be used strictly in
accordance with the specifications set forth in the Agreement and below.

     2.   The "ZD" mark shall not be enclosed in any way by a border or combined
with or incorporated with or in any other words or marks, or modified in any
other way. The "ZD" mark shall be of sufficient size and on an appropriately
contrasting background to make all words plainly legible.

     3.   Licensee will use commercially diligent efforts to use the "ZD" mark
only as a brand or an adjective followed by the common generic term for the
mark, e.g., the "ZD magazine" and shall not use the "ZD" mark in the possessive.

     4.   Whenever reasonable in the context of a particular use of the Marks,
Licensee shall identify such trademark as being used under license from
Licensor.

     5.   The Marks must include the (R) or (/TM/)  symbol, as designated by
Licensor, and the following notice: "ZD and the ZD logo are either registered
trademarks or trademarks of ZD Inc. in the United States and/or other
countries."

          These guidelines may be reasonably amended by Licensor from time to
time upon at least 180 days written notice to Licensee, subject to Licensee's
consent, which shall not be unreasonably withheld.