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                                                                 EXHIBIT 10.33.1


                    INTELLECTUAL PROPERTY SECURITY AGREEMENT

     This Intellectual Property Security Agreement (the "Agreement") is made as
of August 4, 1999, by and between WEBSIDESTORY, INC., a California corporation
("Grantor"), and IMPERIAL BANK, a California chartered bank ("Secured Party").


                                    RECITALS

     A.   Secured Party has agreed to lend to Grantor certain funds (the
"Loan"), and Grantor desires to borrow such funds from Secured Party pursuant to
the terms of a Credit Agreement, dated as of August 4, 1999 (the "Credit
Agreement;" all capitalized terms used herein without definition shall have the
meanings ascribed to them in the Credit Agreement).

     B.   In order to induce Secured Party to enter into the Credit Agreement,
Grantor has agreed to grant a security interest in certain intangible property
to Secured Party for purposes of securing the obligations of Grantor to Secured
Party.

     NOW, THEREFORE, THE PARTIES HERETO AGREE AS FOLLOWS:

     1.   Grant of Security Interest. As collateral security for the prompt and
complete payment and performance of all of Grantor's present or future
indebtedness, obligations and liabilities to Secured Party, Grantor hereby
grants a security interest and mortgage to Secured Party, as security, in and to
Grantor's entire right, title and interest in, to and under the following (all
of which shall collectively be called the "Collateral"):

          (a)  Any and all copyright rights, copyright applications, copyright
registrations and like protections in each work or authorship and derivative
work thereof, whether published or unpublished and whether or not the same also
constitutes a trade secret, now or hereafter existing, created, acquired or
held, including without limitation those set forth on Exhibit A attached hereto
(collectively, the "Copyrights");

          (b)  Any and all trade secrets, and any and all intellectual property
rights in computer software and computer software products now or hereafter
existing, created, acquired or held;

          (c)  Any and all design rights which may be available to Grantor now
or hereafter existing, created, acquired or held;

          (d)  All patents, patent applications and like protections including
without limitation improvements, divisions, continuations, renewals, reissues,
extensions and continuations-in-part of the same, including without limitation
the patents and patent applications set forth on Exhibit B attached hereto
(collectively, the "Patents");

          (e)  Any trademark and servicemark rights, whether registered or not,
applications to register and registrations of the same and like protections, and
the entire goodwill of the business of Grantor connected with and symbolized by
such trademarks, including without limitation those set forth on Exhibit C
attached hereto (collectively, the "Trademarks");

          (f)  Any and all claims for damages by way of past, present and future
infringement of any of the rights included above, with the right, but not the
obligation, to sue for and collect such damages for said use or infringement of
the intellectual property rights identified above;

          (g)  All licenses or other rights to use any of the Copyrights,
Patents or Trademarks, and all license fees and royalties arising from such use
to the extent permitted by such license or rights; and

          (h)  All amendments, renewals and extensions of any of the Copyrights,
Trademarks or Patents; and

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          (i)  All proceeds and products of the foregoing, including without
limitation all payments under insurance or any indemnity or warranty payable in
respect of any of the foregoing.

     2.   Authorization and Request. Grantor authorizes and requests that the
Register of Copyrights and the Commissioner of Patents and Trademarks record
this security agreement.

     3.   Covenants and Warranties. Grantor represents, warrants, covenants and
agrees as follows:

          (a)  Grantor is now the sole owner of the Collateral, except for
non-exclusive licenses granted by Grantor to its customers in the ordinary
course of business;

          (b)  Performance of this Agreement does not conflict with or result in
a breach of any agreement to which Grantor is party or by which Grantor is
bound, except to the extent that certain intellectual property agreements
prohibit the assignment of the rights thereunder to a third party without the
licensor's or other party's consent and this Agreement constitutes an
assignment;

          (c)  During the term of this Agreement, Grantor will not transfer or
otherwise encumber any interest in the Collateral, except for non-exclusive
licenses granted by Grantor in the ordinary course of business or as set forth
in this Agreement;

          (d)  To its knowledge, each of the Patents is valid and enforceable,
and no part of the Collateral has been judged invalid or unenforceable, in whole
or in part, and no claim has been made that any part of the Collateral violates
the rights of any third party;

          (e)  Grantor shall deliver to Secured Party within (30) days of the
last day of each fiscal quarter, a report signed by Grantor, in form reasonably
acceptable to Secured Party, listing any applications or registrations that
Grantor has made or filed in respect of any patents, copyrights or trademarks
and the status of any outstanding applications or registrations. Grantor shall
promptly advise Secured Party of any material change in the composition of the
Collateral, including but not limited to any subsequent ownership right of the
Grantor in or to any Trademark, Patent or Copyright not specified in this
Agreement;

          (f)  Grantor shall (i) protect, defend and maintain the validity and
enforceability of the Trademarks, Patents and Copyrights (ii) use commercially
reasonable efforts to detect infringements of the Trademarks, Patents and
Copyrights and promptly advise Secured Party in writing of material
infringements detected and (iii) not allow any Trademarks, Patents or Copyrights
to be abandoned, forfeited or dedicated to the public without the written
consent of Secured Party, which shall not be unreasonably withheld, unless
Grantor determines that reasonable business practices suggest the abandonment is
appropriate;

          (g)  Grantor shall register or cause to be registered (to the extent
not already registered) with the United States Patent and Trademark Office or
the United States Copyright Office, as applicable, those intellectual property
rights listed on Exhibits A, B and C hereto within thirty (30) days of the date
of this Agreement, Grantor shall register or cause to be registered with the
United States Patent and Trademark Office or the United States Copyright Office,
as applicable, those additional intellectual property rights developed or
acquired by Grantor from time to time in connection with any product prior to
the sale or licensing of such product to any third party (including without
limitation revisions or additions to the intellectual property rights listed on
such Exhibits A, B and C). Grantor shall, from time to time, execute and file
such other instruments, and take such further actions as Secured Party may
reasonably request from time to time to perfect or continue the perfection of
Secured Party's interest in the Collateral;

          (h)  Grantor has not granted a security interest in the Collateral in
favor of any other Person;

          (i)  To its knowledge, except for, and upon, the filing with the
United States Patent and Trademark office with respect to the Patents and
Trademarks and the Register of Copyrights with respect to the Copyrights
necessary to perfect the security interests created hereunder, and except as has
been already made or obtained, no authorization, approval or other action by,
and no notice to or filing with, any United States


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governmental authority or United States regulatory body is required for the
grant by Grantor of the security interest granted hereby or for the execution,
delivery or performance of this Agreement by Grantor in the United States;

          (j)  All information heretofore, herein or hereafter supplied to
Secured Party by or on behalf of Grantor with respect to the Collateral is
accurate and complete in all material respects;

          (k)  Grantor shall not enter into any agreement that would
materially impair or conflict with Grantor's obligations hereunder without
Secured Party's prior written consent, which consent shall not be unreasonably
withheld. Grantor shall not permit the inclusion in any material contract to
which it becomes a party of any provisions that could or might in any way
prevent the creation of a security interest in Grantor's rights and interests
in any property included within the definition of the Collateral acquired under
such contracts; and

          (l)  Upon any executive officer of Grantor obtaining actual knowledge
thereof, Grantor will promptly notify Secured Party in writing of any event
that materially adversely affects the value of any Collateral, the ability of
Grantor to dispose of any Collateral or the rights and remedies of Secured
Party in relation thereto, including the levy of any legal process against any
of the Collateral.

     4.   Secured Party's Rights.  Secured Party shall have the right, but not
the obligation, to take, at Grantor's sole expense, any actions that Grantor is
required under this Agreement to take but which Grantor fails to take, after
fifteen (15) days' notice to Grantor. Grantor shall reimburse and indemnify
Secured Party for all reasonable costs and reasonable expenses incurred in the
reasonable exercise of its rights under this section 4.

     5.   Further Assurances: Attorney in Fact.

          (a)  On a continuing basis, Grantor will make, execute, acknowledge
and deliver, and file and record in the proper filing and recording places in
the United States, all such instruments, including appropriate financing and
continuation statements and collateral agreements and filings with the United
States Patent and Trademark Office and the Register of Copyrights, and take all
such action as may reasonably be deemed necessary or advisable, or as requested
by secured Party, to perfect Secured Party's security interest in all
Copyrights, Patents and Trademarks and otherwise to carry out the intent and
purposes of this Agreement, or for assuring and confirming to Secured Party the
grant or perfection of a security interest in all Collateral.

          (b)  Grantor hereby irrevocably appoints Secured Party as Grantor's
attorney-in-fact, with full authority in the place and stead of Grantor and in
the name of Grantor, from time to time in Secured Party's discretion, to take
any action and to execute any instrument which Secured Party may deem necessary
or advisable to accomplish the purposes of this Agreement, including (i) to
modify, in its sole discretion, this Agreement without first obtaining
Grantor's approval of or signature to such modification by amending Exhibit A,
Exhibit B and Exhibit C, thereof, as appropriate, to include reference to any
right, title or interest in any Copyrights, Patents or Trademarks acquired by
Grantor after the execution hereof or to delete any reference to any right,
title or interest in any Copyrights, Patents or Trademarks in which Grantor no
longer has or claims any right, title or interest, (ii) to file, in its sole
discretion, one or more financing or continuation statements and amendments
thereto, relative to any of the Collateral without the signature of Grantor
where permitted by law and (iii) after the occurrence of an Event of Default, to
transfer the Collateral into the name of Bank or a third party to the extent
permitted under the California Uniform Commercial Code.

     6.   Events of Default.  The occurrence of any of the following shall
constitute an Event of Default under the Agreement:

          (a)  An Event of Default occurs under the Credit Agreement; or

          (b)  Grantor breaches any warranty or agreement made by Grantor in
this Agreement and, as to any breach that is capable of cure, Grantor fails to
cure such breach within five (5) days of the occurrence of such breach.

     7.   Remedies.  Upon the occurrence and continuance of an Event of
Default, Secured Party shall have the right to exercise all the remedies of a
secured party under the California Uniform Commercial Code, including

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without limitation the right to require Grantor to assemble the Collateral and
any tangible property in which Secured Party has a security interest and to
make it available to Secured Party at a place designated by Secured Party.
Secured Party shall have a nonexclusive, royalty free license to use the
Copyrights, Patents and Trademarks to the extent reasonably necessary to permit
Secured Party to exercise its rights and remedies upon the occurrence of an
Event of Default. Grantor will pay any expenses (including reasonable
attorneys' fees) incurred by Secured Party in connection with the exercise of
any Secured Party's rights hereunder, including without limitation any expense
incurred in disposing of the Collateral. All of Secured Party's rights and
remedies with respect to the Collateral shall be cumulative.

     8.   Indemnity. Grantor agrees to defend, indemnify and hold harmless
Secured Party and its officers, employees, and agents against: (a) all
obligations, demands, claims, and liabilities claimed or asserted by any other
party in connection with the transactions contemplated by this Agreement, and
(b) all losses or expenses in any way suffered, incurred, or paid by Secured
Party as a result of or in any way arising out of, following or consequential
to transactions between Secured Party and Grantor, under this Agreement
(including without limitation reasonable attorneys' fees and reasonable
expenses), except for losses arising from or out of Secured Party's gross
negligence or willful misconduct.

     9.   Course of Dealing.  No course of dealing, nor any failure to
exercise, nor any delay in exercising any right, power or privilege hereunder
shall operate as a waiver thereof.

     10.  Attorneys' Fees.  If any action relating to this Agreement is brought
by either party hereto against the other party, the prevailing party shall be
entitled to recover reasonable attorneys' fees, costs and disbursements.

     11.  Amendments.  This Agreement may be amended only by a written
instrument signed by both parties hereto.

     12.  Counterparts.  This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original but all of which
together shall constitute the same instrument.

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     13.  California Law and Jurisdiction; Jury Waiver. This Agreement shall be
governed by the laws of the State of California, without regard for choice of
law provisions. Grantor and Secured Party consent to the exclusive jurisdiction
of any state or federal court located in Santa Clara County, California.
GRANTOR AND SECURED PARTY EACH WAIVE THEIR RESPECTIVE RIGHTS TO A JURY TRIAL OF
ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF THE CREDIT AGREEMENT,
THIS AGREEMENT, OR ANY OF THE TRANSACTIONS CONTEMPLATED HEREIN, INCLUDING
CONTRACT CLAIMS, TORT CLAIMS, BREACH OF DUTY CLAIMS, AND ALL OTHER COMMON LAW
OR STATUTORY CLAIMS.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement on the
day and year first above written.

                                       GRANTOR:

Address of Grantor:                    WEBSIDESTORY, INC.

6450 Lusk Blvd., Suite E205            By: /s/ Michael D. Reynolds
San Diego, CA 92121                        ------------------------------

                                       Its: VP FINANCE & CFO
                                           ------------------------------

Attn: Legal Dept.                      By: [SIGNATURE ILLEGIBLE]
      ----------------------               ------------------------------

                                       Its: C.O.O. AND GENERAL COUNSEL
                                           ------------------------------

                                       SECURED PARTY

Address of Secured Party:              IMPERIAL BANK

226 Airport Parkway                    By: [SIGNATURE ILLEGIBLE]
San Jose, CA 95110-1024                    ------------------------------

                                       Its: S.V.P.
                                           ------------------------------

Attn: Corporate Banking Center

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<TABLE>

<S>                                          <C>

ALL PURPOSE ACKNOWLEDGMENT

State of CALIFORNIA  |
                     | ss.
County of SAN DIEGO  |

On        18 August 1999        before me,              ROBERT E. ANDERSON, Notary Public
   ----------------------------            ----------------------------------------------------------,
                (DATE)                                          (NOTARY)

personally appeared                   Michael D. Reynolds and Michael Christian
                    ----------------------------------------------------------------------------------

[ ] personally known to me     -OR-      [X]  proved to me on the basis of satisfactory evidence to
                                              be the person(s) whose name(s) are subscribed to the
                                              within instrument and acknowledged to me that they
                                              executed the same in their authorized capacity(ies),
                                              and that by their signature(s) on the instrument the
                                              person(s), or the entity upon behalf of which the
                                              person(s) acted, executed the instrument.

             ROBERT E. ANDERSON
[SEAL]         COMM. #1112238                 WITNESS my hand and official seal.
        NOTARY PUBLIC - CALIFORNIA
              SAN DIEGO COUNTY                /s/ Robert E. Anderson
     My Comm. Expires December 14, 2000       --------------------------------------------------------
                                                                  NOTARY'S SIGNATURE




---------------------------------------OPTIONAL INFORMATION-------------------------------------------
The information below is not required by law. However, it could prevent fraudulent attachment of this
acknowledgment to an unauthorized document.

CAPACITY CLAIMED BY SIGNER (PRINCIPAL)                 DESCRIPTION OF ATTACHED DOCUMENT

[ ] INDIVIDUAL
[X] CORPORATE OFFICER                                  INTELLECTUAL PROP SECURITY AGREE

    ----------------------------------------------     ------------------------------------------------
                      TITLE(S)                                     TITLE OR TYPE OF DOCUMENT

[ ] PARTNER(S)                                                               7
[ ] ATTORNEY-IN-FACT                                   ------------------------------------------------
[ ] TRUSTEE(S)                                                        NUMBER OF PAGES
[ ] GUARDIAN/CONSERVATOR
[ ] OTHER:
          ----------------------------------------

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

    ----------------------------------------------     -------------------------------------------------
                                                                      DATE OF DOCUMENT

SIGNER IS REPRESENTING:
NAME OF PERSON(S) OR ENTITY(IES)

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

--------------------------------------------------     ---------------------------------------------------
                                                                           OTHER

</TABLE>
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                                   EXHIBIT B

                                    Patents

<TABLE>
<CAPTION>
                                                                 Registration/Application
       Description                 Registration/Serial Number            Date
       -----------                 --------------------------    ------------------------
<S>                                <C>                           <C>
Internet Website Traffic Flow          09/326,475                      06/04/99
Analysis

</TABLE>
<PAGE>   8
                                   EXHIBIT C

                                   Trademarks

<TABLE>
<CAPTION>
                      Registration/Application          Registration/Application
Description                     Number                             Date
-----------           ------------------------          ------------------------
<S>                         <C>                               <C>
Web Side Story               2,174,768                         07/21/98
Hitbox                       2,174,844                         07/21/98
Traffic                      App. No. 75/444698                Applied March 5, 1998
XY2K                         Not Available                     Applied July 14, 1999
Yep                          App. No. 75/653048                Applied March 3, 1999
</TABLE>


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