<PAGE>

                                                                    EXHIBIT 10.1

                                FOURTH AMENDMENT
                                  OEM AGREEMENT


This Fourth Amendment is entered into effective as of the Amendment Effective
Date set forth below by and between Hyperion Solutions Corporation ("Hyperion")
and SPSS, Inc. ("SPSS") for the purpose of amending the OEM Agreement between
the parties dated November 5, 2004 as amended by the First Amendment dated
December 1, 2004; the Second Amendment dated December 1, 2004; and, the Third
Amendment dated December 30, 2004 (collectively, the "Agreement").

WHEREAS, Hyperion and SPSS now desire to amend this Agreement to (1) permit SPSS
to port Hyperion System 9 Software to the IBM AS/400 platform or any direct
successor platform; and (2) have SPSS maintain and support, but not distribute
or sublicense, the ported Hyperion System 9 Software.

NOW, THEREFORE, in consideration of the foregoing, the parties agree as follows:

1.   Capitalized terms not defined herein have the same meaning as in the
     Agreement.

2.   Amend Section 2(a) by inserting the following terms at the end of the
     second sentence: "and the source code access controls and handling
     requirements contained in Exhibit I."

3.   Amend Section 2(a) by inserting the following terms at the end of such
     Section: "SPSS shall not provide access to Source Code to any third party
     or subcontract some or all of its port development obligations herein to
     any third party (without limitation subcontractors or consultants) without
     Hyperion's prior written consent which Hyperion may give or withhold in its
     sole reasonable discretion. Notwithstanding the foregoing, SPSS shall be
     liable for subcontractor's and any other third party's compliance with the
     terms of this Agreement, including but not limited to the Source Code
     controls and procedures set forth in Exhibit I, as well as their
     performance of the port development services.

4.   Amend Section 2(b) by adding the following sentences at the of the
     paragraph:

     "Notwithstanding the foregoing, Hyperion does not grant to SPSS any right
     to distribute nor sublicense any Hyperion System 9 Software and successor
     versions (Ported or Non-Ported). For avoidance of doubt, any grant of
     license to distribute Software hereunder shall not apply to Hyperion System
     9 Software and successor versions."

5.   Amend Section 2(d) by adding the following sentences at the end of the
     paragraph:

     "Notwithstanding the foregoing, Hyperion does not grant to SPSS any right
     to distribute nor sublicense any Hyperion System 9 Software and successor
     versions (Ported or Non-Ported). For avoidance of doubt, any grant of
     license to distribute Software hereunder shall not apply to Hyperion System
     9 Software and successor versions."

6.   Amend Section 2(g) by adding the following sentences at the end of the
     paragraph:

     "Notwithstanding the foregoing, and solely in connection with Hyperion
     System 9 Software, and successor versions, (1) Hyperion shall offer annual
     Support to End Users with every ported Hyperion System 9 Software, and
     successor versions, Hyperion distributes; (2) SPSS shall provide First,
     Second and Third Level Support to such End Users on behalf of Hyperion in
     accordance with Exhibit II to this Amendment; (3) SPSS shall continue to
     develop, support and maintain, as applicable, its


<PAGE>

     own intellectual property that enables Hyperion System 9 Software, and
     successor versions, to be compatible with the IBM AS/400 platform or any
     direct successor platform; and (4) in consideration of the foregoing 2 and
     3 Hyperion shall pay SPSS * percent (*%) of the actual End User annual
     Support fee charged by Hyperion for standard Hyperion Support purchased by
     the End User. The foregoing *% amount is based on Hyperion's standard
     Support program which is the equivalent support level that SPSS will
     provide as described in Exhibit II. The parties shall in good faith
     negotiate a mutually acceptable amount in the event that SPSS agrees to
     provide more than the standard support services that are currently
     described in Exhibit II. Within thirty (30) days following the end of each
     calendar quarter, for each Hyperion customer who purchases or renews
     Support for the ported version of Hyperion System 9, or a successor
     version, Hyperion shall report to SPSS in writing the End-User's name, the
     actual annual End User Support fee charged by Hyperion and the amount owed
     to SPSS. Hyperion shall pay SPSS the amount due within forty-five (45) days
     of the close of the quarter."

7.   Amend Section 2(h) by adding the following sentences at the end of the
     paragraph:

     "Notwithstanding the foregoing, Hyperion does not grant to SPSS any right
     to distribute nor sublicense any Hyperion System 9 Software and successor
     versions (Ported or Non-Ported). For avoidance of doubt, any grant of
     license to distribute Software hereunder shall not apply to Hyperion System
     9 Software and successor versions."

8.   Amend Section 2(j) by adding the following sentences at the end of the
     paragraph:

     "Notwithstanding the foregoing, Hyperion does not grant to SPSS any right
     to distribute nor sublicense any Hyperion System 9 Software and successor
     versions (Ported or Non-Ported). For avoidance of doubt, any grant of
     license to distribute Software hereunder shall not apply to Hyperion System
     9 Software and successor versions."

9.   Amend Section 3(a) by adding the following sentences at the end of the
     paragraph:

     "Notwithstanding the foregoing and subject to a potential referral fee, and
     solely in connection with Hyperion System 9 Software and successor
     versions, Hyperion may distribute and sublicense the ShowCase AS/400 Port
     to any End User, including any of SPSS' Named Accounts without SPSS'
     approval and Hyperion shall fulfill its orders for the ShowCase AS/400
     Port."

10.  Amend Section 4(a) as follows: (1) Delete "three (3) years" and replace it
     with "eight (8) years."

11.  Delete Section 5(c) in its entirety.

12.  Amend Section 6(a) by adding the following sentences at the end of the
     paragraph:

     "If an End User who purchased licenses for the ShowCase AS/400 Port from
     SPSS, or any existing SPSS end user customer who is not a current Hyperion
     customer and who purchased licenses for any SPSS product ported to the IBM
     iSeries platform, desires to purchase Hyperion System 9 licenses, or a
     successor version, of the ShowCase AS/400 Port, then SPSS may refer such
     End User or customer to Hyperion by completing the Hyperion Marketing
     Assistance Fee (MAF) qualifying form set forth in Exhibit III and
     submitting it to Hyperion via fax or email as indicated in Exhibit III to
     register the sales opportunity for approval by Hyperion. A MAF request is
     valid for six (6) months after approval by Hyperion and no MAF request can
     be outstanding for more than 6 months. If, and only if, (i) such End User
     contracts directly with Hyperion by signing Hyperion's Software License
     Agreement for the purchase of such licenses, and (ii) such End User orders
     the Software licenses directly from Hyperion, then SPSS shall be entitled
     to a * percent (*%) referral fee based on the actual software license
     revenue Hyperion receives from the End User; provided, however, that (a)
     the maximum referral fee amount that can be received by SPSS for a single
     opportunity is either $* USD for the



*Confidential treatment requested; material has been filed separately with the
Securities and Exchange Commission.

<PAGE>

     ShowCase AS/400 Port customer referrals only or $* USD for all other
     customer referrals permitted under this Section. Within thirty (30) days
     following the end of each calendar quarter, Hyperion shall report to SPSS
     in writing if any referrals closed within such calendar quarter. Included
     in such report shall be the End-User's name and the amount of the license
     fee charged to the End User by Hyperion. Hyperion shall pay SPSS any
     referral fees due within forty-five (45) days of the close of the quarter
     in which a referred license transaction was closed. The parties agree that
     if an End-User wishes to transfer to Hyperion System 9, or a successor
     version, during a current maintenance period that SPSS will not credit such
     End-User any of the maintenance fees paid to SPSS."

13.  Delete Section 6(b) and replace it with the following:

     "6(d) SUPPORT FOR SHOWCASE AS/400 PORT SALES BY HYPERION. SPSS shall
     provide First, Second and Third Level Support on behalf of Hyperion to
     those customers who have purchased licenses and related Support for the
     ShowCase AS/400 Port from Hyperion or its partners and Hyperion shall pay
     SPSS the amount set forth in Section 2(g) above. The End User shall
     contract directly with Hyperion for the license and Support of the ShowCase
     AS/400 Port, and then SPSS shall provide First, Second and Third Support
     directly to such End Users on behalf of Hyperion. The parties shall in good
     faith define a mutually acceptable process for providing such Support to
     End Users before the Ported Hyperion System 9 Software becomes commercially
     available."

14.  Amend Section I of Exhibit A by adding the following Software:

         -    Hyperion System 9 BI+ Platform Bundle (All BI+ Modules)
         -    Hyperion System 9 BI+ Foundation
         -    Hyperion System 9 BI+ Interactive Reporting
         -    Hyperion System 9 BI+ Essbase Analytics
         -    Hyperion System 9 BI+ Enterprise Analytics
         -    Hyperion System 9 BI+ Web Analysis
         -    Hyperion System 9 BI+ Financial Reporting
         -    Hyperion System 9 BI+ Production Reporting
         -    Hyperion System 9 BI+ Production Reporting Stand-Alone
         -    Hyperion System 9 Planning & Essbase Analytics
         -    Hyperion System 9 Planning & Application-Specific Essbase
         -    Hyperion System 9 Planning Standard Edition

15.  Amend Section II of Exhibit A by adding the following sentences immediately
     following the table:

     "Notwithstanding the foregoing, Hyperion does not grant to SPSS any right
     to distribute nor sublicense any Hyperion System 9 Software and successor
     versions (Ported or Non-Ported). For avoidance of doubt, any grant of
     license to distribute Software hereunder shall not apply to Hyperion System
     9 Software and successor versions."

16.  Delete the Option 1 and Option 2 tables in Section III of Exhibit A and
     replace it with the following tables and add the following paragraph to
     this Section III:

--------------------------------------------------------------------------------
                     EXISTING SHOWCASE AS/400 PORT CUSTOMERS
--------------------------------------------------------------------------------
                                 SUBLICENSE FEES
--------------------------------------------------------------------------------
                      Local List price, less *% discount**
--------------------------------------------------------------------------------

--------------------------------------------------------------------------------
                       NEW SHOWCASE AS/400 PORT CUSTOMERS
--------------------------------------------------------------------------------
                                 SUBLICENSE FEES
--------------------------------------------------------------------------------
                      Local List price, less *% discount**
--------------------------------------------------------------------------------



*Confidential treatment requested; material has been filed separately with the
Securities and Exchange Commission.

<PAGE>

     Notwithstanding the foregoing Sublicense Fees, and solely during the period
     from the Effective Date of this Amendment until either such time that the
     ported Hyperion System 9 Software becomes commercially available or through
     December 31, 2007, whichever occurs first, the Sublicense Fees payable by
     SPSS to Hyperion shall be equal to the local list price, less *%
     discount**.

17.  Add a new Exhibit I, which is attached to this Fourth Amendment.

18.  The Second Amendment is hereby deleted in its entirety.

19.  The terms and conditions of this Fourth Amendment shall supersede the terms
     and conditions of the Agreement in the event of a conflict. Otherwise, the
     terms and conditions of the Agreement remain unchanged and in full force
     and effect.


By signing this Fourth Amendment, the parties agree to the terms and conditions
set forth herein as of the Fourth Amendment Effective Date written below.


HYPERION SOLUTIONS CORPORATION             SPSS, INC.

By  /s/ Robert Gersten                     By  /s/ Jack Noonan
  -----------------------------------        -----------------------------------

Name    Robert Gersten                     Name    Jack Noonan
    ---------------------------------           --------------------------------

Title   Chief Development Officer          Title   President and CEO
      -------------------------------            -------------------------------

AMENDMENT EFFECTIVE DATE:  January 3, 2007
                           ---------------
                           (To be completed by Hyperion)




*Confidential treatment requested; material has been filed separately with the
Securities and Exchange Commission.


<PAGE>

                                    EXHIBIT I

                   SOURCE CODE ACCESS CONTROLS AND PROCEDURES



1.   All Hyperion source code ("Source Code") delivered to SPSS pursuant to this
     Agreement will be stored at SPSS' facility in a source code repository,
     staged on an authorized user's workstation, or included in backup/archival
     media stored in a secure, offsite facility. The workstation on which any
     Source Code is staged shall be in a secure and controlled environment (for
     example, any SPSS location requiring badge-reader access for entry), or
     protected through encryption. SPSS shall grant access to the Hyperion
     Source Code only to SPSS employees and authorized contractors who require
     access for the purpose of performing the port of the Source Code, for
     development, maintenance and support of the ShowCase AS/400 Port
     contemplated by this Agreement, and for system administration for the
     system(s) storing the Source Code. All access to Hyperion Source Code shall
     be user-id and password protected.

2.   All SPSS employees or subcontractors who have been pre-approved by Hyperion
     in writing pursuant to Section 2(a) of the Agreement ("Approved
     Subcontractors") who receive access to the Source Code will be advised that
     such Source Code is confidential information of Hyperion and that sharing
     source access user-ids or passwords is strictly forbidden.

3.   SPSS and its Approved Subcontractors will maintain an audit log for all
     transactions concerning the granting or changing of access to Hyperion
     Source Code.

4.   SPSS will notify Hyperion promptly (i.e., within five (5) business days) of
     the following information for individuals SPSS or its Approved
     Subcontractors authorized to access the Hyperion Source Code: name, status
     (employee or contractor), whether access is restricted or unrestricted,
     access start date, expected access end date (if known), the name of the
     authorizing manager, and the date authorization was granted. Hyperion must
     agree in advance to SPSS granting access to any contractor personnel.

5.   Hyperion may request audit file reports on its Source Code access
     periodically, but no more than once a quarter unless Hyperion has a
     reasonable basis to believe that SPSS is not in compliance with this
     Exhibit. Hyperion can request from SPSS in writing an explanation of access
     activity of any individual at any time, including SPSS' grant of initial
     access, and SPSS agrees to respond to such requests in writing within five
     (5) business days. In the event that Hyperion is not satisfied with the
     SPSS explanation, then the individual whose access has been questioned by
     Hyperion shall be immediately denied access to the Hyperion Source Code
     unless and until such time as Hyperion consents to such access being
     restored.


<PAGE>

                                   EXHIBIT II

                        LEVEL 1, 2 AND 3 SUPPORT SERVICES



SUPPORTED TECHNOLOGY


SPSS will answer support questions for the current release of the Software and
one (1) prior release back. SPSS will provide corrections to known errors in the
current release of the Software only if and when such corrections are made
available by SPSS.

SUPPORT ACCESS:
SPSS shall only be required to provide support to the designated support contact
of the customer.

PROBLEM PRIORITY:
All support requests will be assigned a tracking number by SPSS which will be
provided to the customer's designated support representative. At the time a
problem is reported, the requestor will be asked to provide an assessment of the
impact the problem is having on the customer. The following designations will be
used to assign problem severity:

>    Severity 1 -- Critical problem. Application unavailable. No acceptable
     workaround available.
>    Severity 2 -  High Impact. Function limited or workaround difficult to
     implement.
>    Severity 3 -- Low Impact. Cosmetic change such as screen wording or a
     typographical error.

HOURS OF OPERATION:
International Telephone Support Business Hours:
a. Americas:                       8:00 A.M. to 8:00 P.M. EST
b. Europe, Middle East, Africa:    8:30 to 18:00 GMT and CET
c. Japan:                          9:00 to 17:00 Japan Time
d. Asia Pacific:                   9:00 to 17:00 Singapore Time
                                   (does not include Japan)

SERVICE MEASURES:
Customer shall receive an initial response to their problem as follows:


--------------------------------------------------------------------------------
Severity          Reporting Method       Estimated Service Level
--------------------------------------------------------------------------------
1,2,3             Telephone              100% - Responded to in 4
                                         business hours
--------------------------------------------------------------------------------
1,2,3             Email                  100% - Responded to in 4
                                         business hours
--------------------------------------------------------------------------------

Customer shall receive updates on the reported problem as follows:

--------------------------------------------------------------------------------
Severity          Frequency
--------------------------------------------------------------------------------
1                 Daily (unless otherwise mutually agreed upon)
--------------------------------------------------------------------------------
2                 Daily (unless otherwise mutually agreed upon)
--------------------------------------------------------------------------------
3                 Weekly (unless otherwise mutually agreed upon)
--------------------------------------------------------------------------------

SPSS will also make available to customer access to an online knowledgebase.
This online system can be accessed any time of the day or week.


<PAGE>

                                   EXHIBIT III
                                  REFERRAL FORM

--------------------------------------------------------------------------------

        HYPERION GLOBAL PARTNER PROGRAM                     [HYPERION LOGO]

--------------------------------------------------------------------------------

    HYPERION MARKETING ASSISTANCE FEE (MAF)

                QUALIFYING FORM                              December 2006

================================================================================


Customer Name / Country
                                       -----------------------------------------

Global Region                           Americas         EMEA           APAC
NA Sales Region (Circle One)            West     Central      East    South-East
Named Account                YES    NO
Public Sector                YES    NO

Customer Contact Name & Phone
                                       -----------------------------------------
Siebel Opportunity ID
                                       -----------------------------------------
Date of Introduction
                                       -----------------------------------------
Anticipated Purchase Amount
                                       -----------------------------------------
Actual MAF%
                                       -----------------------------------------
Description of Opportunity
                                       -----------------------------------------


                           Hyperion Solutions Approval
--------------------------------------------------------------------------------
      Name           Organization              Signature        Date of Approval
--------------------------------------------------------------------------------
                 Direct Sales Manager
--------------------------------------------------------------------------------
                 Regional Sales Director
--------------------------------------------------------------------------------
                 Global Partner Programs
--------------------------------------------------------------------------------

                           Hyperion Solutions Approval
--------------------------------------------------------------------------------
      Name           Organization              Signature        Date of Approval
--------------------------------------------------------------------------------
                 GEO VP
--------------------------------------------------------------------------------
                 VP, Global Partner Sales
--------------------------------------------------------------------------------


Partner Information

Company Identification Number
                                       -----------------------------------------
Company Name
                                       -----------------------------------------
Contact Name & Title
                                       -----------------------------------------
Contact Email Address / Phone No#
                                       -----------------------------------------
Payment Method (Check or Wire)
                                       -----------------------------------------
Mailing Address/Account #
                                       -----------------------------------------

                                       -----------------------------------------


--------------------------------------------------------------------------------
Note: You may submit signed approved MAF forms via fax 408-496-7750 or email at
partners@hyperion.com
--------------------------------------------------------------------------------