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                                                                   EXHIBIT 10.21

                         PATENT CROSS-LICENSE AGREEMENT

      This PATENT CROSS-LICENSE AGREEMENT is entered into by and between
WebSideStory, Inc. ("WSS"), a Delaware corporation, having its principal place
of business at 10182 Telesis Court, San Diego, CA 92121, and NetIQ Corporation
("NETIQ"), a Delaware corporation having its principal place of business at 3553
North First Street, San Jose CA 95134, and is effective as of the 12th day of
December 2003 (the "AGREEMENT DATE").

                                    AGREEMENT

In consideration of the mutual promises set forth in this agreement, the receipt
and sufficiency of which are acknowledged, and intending to be bound, the
parties agree as follows:

1.    DEFINITIONS.

      1.1   As used in this Agreement, the term "NETIQ LICENSED PATENTS" shall
mean all Patents issued or issuing on patent applications filed on or prior to
the Effective Date, or filed subsequent thereto but receiving, or entitled to
receive, the benefit of a filing date on or prior to the Effective Date, and as
to which NetIQ has the right at any time during the term of the Agreement to
grant licenses or releases of the scope or within the scope of the licenses and
releases granted in the Agreement. If the grant or exercise of rights under a
Patent that would otherwise be a Licensed Patent requires or results in the
payment of a royalty or penalty or other consideration by the grantor to another
(except for payments for inventions made by such other while employed by the
grantor), then that Patent shall not be a Licensed Patent until and unless WSS
or its affected Subsidiary undertakes to reimburse the grantor for the payment
so made.

      1.2   As used in this Agreement, the term "WSS LICENSED PATENTS" shall
mean all Patents issued or issuing on patent applications filed on or prior to
the Effective Date, or filed subsequent thereto but receiving, or entitled to
receive, the benefit of a filing date on or prior to the Effective Date, and as
to which WSS has the right at any time during the term of the Agreement to grant
licenses or releases of the scope or within the scope of the licenses and
releases granted in the Agreement. If the grant or exercise of rights under a
Patent that would otherwise be a Licensed Patent requires or results in the
payment of a royalty or penalty or other consideration by a grantor to another
(except for payments for inventions made by such other while employed by the
grantor), then that Patent shall not be a Licensed Patent until and unless NetIQ
or its affected Subsidiary undertakes to reimburse the grantor for the payment
so made.

      1.3   As used in this Agreement, the term "NETIQ LICENSED PRODUCTS" shall
mean any products or services of NetIQ or its Subsidiaries relating to the web
analytics market, including, but not limited to WebTrends Reporting Service,
WebTrends Reporting Center, WebTrends Intelligence Suite, and WebTrendsLive.

      1.4   As used in this Agreement, the term "WSS LICENSED PRODUCTS" shall
mean any products or services of WSS or its Subsidiaries relating to the web
analytics market, including, but not limited to HitBox Enterprise, HitBox
Professional, and HitBox Commerce.

CERTAIN MATERIAL (INDICATED BY AN ASTERISK) HAS BEEN OMITTED FROM THIS DOCUMENT
PURSUANT TO A REQUEST FOR CONFIDENTIAL TREATMENT. THE OMITTED MATERIAL HAS BEEN
FILED SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION.

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      1.5   As used in this Agreement, the term "LICENSED PRODUCTS" shall mean
the NetIQ Licensed Products or the WSS Licensed Products, as the case may be.

      1.6   As used in this Agreement, the term "PARTY" shall mean WSS or NetIQ,
as the case may be.

      1.7   As used in this Agreement, the term "PATENTS" shall mean all classes
or types of patents other than design patents (including, without limitation,
originals, divisions, continuations, continuations-in-part, extensions or
reissues) in all countries of the world.

      1.8   As used in this Agreement, the term "RESTRICTED PARTY" shall mean
the entities listed on Exhibit A, and their respective successors and assigns.

      1.9   As used in this Agreement, the term "SUBSIDIARY" shall mean any
corporation, partnership, joint venture, limited liability or other entity, now
or hereafter, in which a Party:

      (a)   owns or controls (either directly or indirectly) or originally
            contributed (either directly or indirectly) at least fifty percent
            (50%) of the tangible and intangible assets of such entity; and

      (b)   owns or controls (either directly or indirectly) either of the
            following:

            (1)   if such entity has voting shares or other securities, at least
                  fifty percent (50%) of the outstanding shares or securities
                  entitled to vote for the election of directors or similar
                  managing authority and such entity is under no obligation
                  (contractual or otherwise) to directly or indirectly
                  distribute more than seventy percent (70%) of its profits to a
                  third party, or

            (2)   if such entity does not have voting shares or other
                  securities, at least fifty percent (50%) of the ownership
                  interest that represents the right to make decisions for such
                  entity and an interest sufficient to receive at least thirty
                  percent (30%) of the profits and/or losses of such entity.

      (c)   An entity shall be deemed to be a Subsidiary under the Agreement
            only so long as all requisite conditions of being a Subsidiary are
            met.

      1.8   As used in this Agreement, the term "EFFECTIVE DATE" means the date
upon which NetIQ pays WSS the License Fee.

2.    MUTUAL RELEASES.

      2.1   By NetIQ. As of the Effective Date, each of NetIQ and its
Subsidiaries hereby releases, acquits and forever discharges WSS and its
Subsidiaries that are Subsidiaries as of the Effective Date or that become
Subsidiaries during the term of the Agreement, and its and their officers,
directors, shareholders, distributors and customers, direct and indirect, from
any and all claims or liability for infringement (direct, indirect or
contributory) of any NetIQ Licensed Patent that arose prior to the Effective
Date, to the extent such infringement would have been

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licensed under the license granted to the licensed Party if such license had
been in existence at the time of such infringing activity. The foregoing release
shall in no event extend to Restricted Parties or the products or services of
Restricted Parties.

      2.2   By WSS. As of the Effective Date, each of WSS and its Subsidiaries
hereby releases, acquits and forever discharges NetIQ and its Subsidiaries that
are Subsidiaries as of the Effective Date or that become Subsidiaries during the
term of the Agreement, and its and their officers, directors, shareholders,
distributors and customers, direct and indirect, from any and all claims or
liability for infringement (direct, indirect or contributory) of any WSS
Licensed Patent that arose prior to the Effective Date, to the extent such
infringement would have been licensed under the license granted to the licensed
Party if such license had been in existence at the time of such infringing
activity. The foregoing release shall in no event extend to Restricted Parties
or the products or services of Restricted Parties.

3.    LICENSES.

      3.1   NetIQ License to WSS. Subject to the terms and conditions of the
Agreement and on the Effective Date, NetIQ hereby grants to WSS and its
Subsidiaries, a non-exclusive, non-transferable (except as provided in Section 8
with respect to assignment), worldwide, royalty-free license, without the right
to sublicense, under the NetIQ Licensed Patents, to:

      (a)   make, use, sell (directly or indirectly), offer to sell, import and
            otherwise dispose of all WSS Licensed Products, including through
            original equipment manufacturers and value added resellers, who are
            not Restricted Parties and who co-brand or private label the WSS
            Licensed Products; and

      (b)   make, have made, use and/or import any equipment and practice any
            method or process for the manufacture, use and/or sale of WSS
            Licensed Products; and

      (c)   have made WSS Licensed Products by another manufacturer for supply
            solely to the licensed party for use, import, sale, offer for sale
            or disposition by the licensed party pursuant to the license granted
            above in Section 3.1(a), above.

      3.2   WSS License to NetIQ. Subject to the terms and conditions of the
Agreement and on the Effective Date, WSS hereby grants to NetIQ and its
Subsidiaries, a non-exclusive, non-transferable (except as provided in Section 8
with respect to assignment), worldwide, royalty-free license, without the right
to sublicense, under the WSS Licensed Patents, to:

      (a)   make, use, sell (directly or indirectly), offer to sell, import and
            otherwise dispose of all NetIQ Licensed Products, including through
            original equipment manufacturers and value added resellers, who are
            not Restricted Parties and who co-brand or private label the NetIQ
            Licensed Products; and

      (b)   make, have made, use and/or import any equipment and practice any
            method or process for the manufacture, use and/or sale of NetIQ
            Licensed Products; and

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      (c)   have made NetIQ Licensed Products by another manufacturer for supply
            solely to the licensed party for use, import, sale, offer for sale
            or disposition by the licensed party pursuant to the license granted
            above in Section 3.2(a), above.

      3.3   License Term. The term of each license granted hereunder shall be
the life of the affected Patent. The term of the Agreement shall continue until
the last to expire of the Licensed Patents.

4.    PAYMENT.

      Within two (2) business days of the Agreement Date, [***] will wire to
[***] the sum of [***] (the "LICENSE PAYMENT") using the following wire
instructions:

[***]

Checking Account Name:     [***]
Routing Number:   [***]
Account Number:   [***]
Swift Code:       [***]

5.    PUBLIC ANNOUNCEMENT AND CONFIDENTIALITY.

      On or promptly after the Effective Date, the parties will issue a press
release in the form attached hereto as Exhibit B. Notwithstanding the foregoing,
the Parties shall maintain the terms and conditions of this Agreement in
confidence and shall not disclose them to any third party, except (a) with the
prior written consent of the other Party; (b) as may be required by law or legal
process; (c) to its attorneys, accountants and professional advisors; and (d) to
potential acquiring parties and other permitted assignees under Section 8.1 and
subject to a reasonable form of non-disclosure agreement.

6.    WARRANTIES AND DISCLAIMERS.

      6.1   NetIQ Warranty. NetIQ represents and warrants that: (i) the person
signing this agreement on behalf of NetIQ has been duly authorized to do so by
all necessary corporate or other required action and has the power and authority
to execute this agreement on NetIQ's behalf; (ii) the obligations described in
this agreement are legal, valid, and binding obligations of NetIQ enforceable
against it in accordance with the terms set forth in this agreement, except as
the same may be limited by (a) applicable bankruptcy, insolvency,
reorganization, moratorium or other laws of general application affecting
enforcement of creditors' rights and (b) general principles of equity that
restrict the availability of equitable remedies; and (iii) NetIQ is not
restricted or prohibited, contractually or otherwise, from entering into and
performing any of the terms or covenants contained in this agreement.

      6.2   WSS Warranty. WSS represents and warrants that: (i) the person
signing this agreement on behalf of WSS has been duly authorized to do so by all
necessary corporate or other required action and has the power and authority to
execute this agreement on WSS' behalf;

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

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(ii) the obligations described in this Agreement are legal, valid, and binding
obligations of WSS enforceable against it in accordance with the terms set forth
in this Agreement, except as the same may be limited by (a) applicable
bankruptcy, insolvency, reorganization, moratorium or other laws of general
application affecting enforcement of creditors' rights and (b) general
principles of equity that restrict the availability of equitable remedies; and
(iii) WSS is not restricted or prohibited, contractually or otherwise, from
entering into and performing any of the terms or covenants contained in this
Agreement.

      6.3   Disclaimers of Other Warranties. Except as provided in Section 6.1
and 6.2 above, neither Party makes any representations or extends any warranties
of any kind, either express or implied, or assumes any responsibilities
whatsoever with respect to the manufacture, sale or other disposition by the
other Party, its Subsidiaries, vendees or transferees, of Licensed Products
incorporating or making use of inventions claimed in such Party's Patents.
Without limiting the generality of the foregoing, nothing contained in the
Agreement shall be construed as:

      (a)   a warranty or representation by either of the Parties as to the
            validity, enforceability or scope of any Patent;

      (b)   a warranty or representation that any manufacture, sale, lease, use
            or other disposition of Licensed Products will be free from
            infringement of any patent rights or other intellectual property
            rights of either Party or any third party;

      (c)   an agreement to bring or prosecute actions or suits against third
            parties for infringement or conferring any right to bring or
            prosecute actions or suits against third parties for infringement;

      (d)   conferring any right to use in advertising, publicity, or otherwise,
            any trademark, trade name or names, or any contraction, abbreviation
            or simulation thereof, of either party;

      (e)   conferring by implication, estoppel or otherwise, upon any party
            licensed hereunder, any license or other right under any patents,
            copyright, maskwork, trade secret, trademark other intellectual
            property right except the licenses and rights expressly granted
            hereunder; or

      (f)   an obligation to furnish any technical information or know-how.

7.    LIMITATION OF LIABILITY. IN NO EVENT WILL EITHER PARTY BE LIABLE TO THE
OTHER PARTY FOR CONSEQUENTIAL, INCIDENTAL, INDIRECT, OR PUNITIVE DAMAGES FOR ANY
CAUSE OF ACTION, WHETHER IN CONTRACT, TORT, OR OTHERWISE, ARISING UNDER THIS
AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREUNDER. Consequential, incidental,
and indirect damages include, but are not limited to, lost profits, lost
revenue, and loss of business opportunity, whether or not such Party was aware
or should have been aware of the possibility of these damages.

8.    ASSIGNMENT.

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      8.1   Neither Party may assign to another party this Agreement, or any
rights or obligations under the Agreement, whether by operation of contract, law
or otherwise, except (a) with the express written consent of the other Party, or
(b) in connection with a merger, acquisition or sale to a third party of
substantially all of a Party's assets to which this Agreement relates, and
subject, in each case, to such assignee's written agreement to be bound to the
terms of the Agreement. Any attempted assignment by a Party in violation of this
prohibition shall be void. In the event of a prohibited assignment or attempted
assignment by a Party under this Section 8.1, the other Party shall have the
right to immediately terminate this Agreement. In the event of a permitted
assignment under this Section 8.1, the licenses granted under the Agreement
shall only extend to the Licensed Products marketed or under development by the
assigning Party at the time of the assignment and derivatives thereof.

      8.2   Irrespective of Section 8.1, neither Party may assign to a
Restricted Party this Agreement or any of the licenses granted hereunder,
whether by operation of contract, law or otherwise, except with the express
written consent of the other Party. For purposes of the Agreement, an
"assignment" to a Restricted Party shall be deemed to include, without
limitation, attempted assignments or transfers pursuant to any of the following:
(a) a merger of a Party with a Restricted Party, whether or not the Party is the
surviving entity; (b) the acquisition of more than twenty percent (20%) of any
class of a Party's voting stock (or any class of non-voting security convertible
into voting stock) by a Restricted Party (whether in a single transaction or
series of transactions); (c) the sale or other transfer of more than fifty
percent (50%) of a Party's assets (whether in a single transaction or series of
transactions) to a Restricted Party; and (d) the acquisition of a Restricted
Party or more than fifty percent (50%) of its assets, including where the
Restricted Party would otherwise be a Subsidiary (each a "Restricted Party
Transaction"). In the event of a Restricted Party Transaction the licenses
granted under the Agreement shall only extend to the Licensed Products marketed
or under development by the assigning Party at the time of the assignment and
derivatives thereof.

      8.3   Any license or release granted by a Party in respect of a Licensed
Patent shall be binding on any successor of that Party in ownership or control
of the Licensed Patent.

9.    MISCELLANEOUS.

      9.1   Notices. All notices or other communications to be given hereunder
shall be in writing and delivered either by telecopy (confirmation by US mail)
or by next or second-day courier, courier charges prepaid, and addressed to the
appropriate party as set forth below.

            If to Licensor:     WebSideStory, Inc.
                                10182 Telesis Court, 6th Floor
                                San Diego, CA 92121
                                Attn: Office of the CEO
                                Facsimile: 858-546-0695

            If to Licensee:     NetIQ Corporation
                                3553 N. First St.
                                San Jose, CA 95134
                                Attn: General Counsel
                                Facsimile: 408-856-3777

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Notices delivered personally shall be effective upon delivery and notices
delivered by private courier shall be effective upon their receipt by the party
to whom they are addressed.

      9.2   Severability and Construction. If any provision of this agreement
shall be held illegal or unenforceable, that provision shall be limited or
eliminated to the minimum extent necessary so that this Agreement shall
otherwise remain in full force and effect and be enforceable. This Agreement has
been negotiated between the Parties and neither Party shall be deemed the
"drafter" for purposes of the construction and interpretation of this Agreement.
The captions used in this Agreement are included for convenience of reference
only and shall be ignored in the construction and interpretation of this
Agreement.

      9.3   Waiver. A waiver by either Party of its rights hereunder shall not
be binding unless contained in a writing signed by an authorized representative
of the Party waiving its rights, and such waiver shall not be construed as a
waiver of any other rights hereunder. The nonenforcement or waiver of any
provision on one occasion shall not constitute a waiver of such provision on any
other occasion unless expressly so agreed in writing.

      9.4   Counterparts. This agreement may be executed in any number of
original or facsimile counterparts, each of which shall be deemed an original,
and all of which together shall constitute one agreement. This agreement shall
become effective when each Party shall have received a faxed counterpart
executed by the other Party.

      9.5   Independent Contractors. Each Party hereto shall be and remain an
independent contractor, and nothing herein shall be deemed to constitute the
Parties as partners. Neither party shall have any authority to act, or attempt
to act, or represent itself, directly or by implication, as an agent of the
other or in any manner assume or create, or attempt to assume or create, any
obligation on behalf of or in the name of the other, nor shall either be deemed
the agent or employee of the other.

      9.6   Governing Law. This agreement shall be governed by and construed and
enforced in accordance with the laws of the State of California and the federal
laws of the United States, without regard to conflict of laws.

      9.7   Entire Agreement. This agreement constitutes the entire agreement
between the Parties hereto concerning the subject matter hereof, and no prior or
contemporaneous oral or written communication shall be a part of the Parties'
agreement. This agreement may not be modified except by a writing signed by an
authorized representative of each Party.

      9.8   Force Majeure. Neither party shall be responsible for delays or
failure of performance resulting from acts beyond the reasonable control of such
party. Such acts shall include, without limitation, acts of God, strikes,
walkouts, riots, acts of war, terrorism, epidemics or governmental regulations.

      9.9   Attorneys' Fees and Costs. The prevailing party in any mediation,
arbitration, litigation, or other proceeding related to or arising out of this
Agreement shall be entitled to recover from the other party its reasonable
attorneys' fees and costs.

IN WITNESS WHEREOF, the Parties hereto have caused this agreement to be executed
as of the date first written above by their duly authorized officers.

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NETIQ CORPORATION                      WEBSIDESTORY, INC.
("NetIQ")                              ("WSS")

By: /s/ Charles M. Boesenber           By: /s/ Jeffrey W. Lunsford
    --------------------------------       -----------------------------
Print Name: Charles M. Boesenber       Print Name: Jeffrey W. Lunsford

Title: CEO and Chairman of the Board   Title: Chairman & CEO

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                                    EXHIBIT A

                               Restricted Parties

[***]

*** Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

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                                    EXHIBIT B

                                  Press Release

                                   [attached]

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