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                                                                    EXHIBIT 10.9

                           PATENT SECURITY AGREEMENT

            Patent Security Agreement, dated as of July 28, 2005 (as amended,
restated or otherwise modified from time to time, the "Patent Security
Agreement"), between MediaDefender, Inc., a Delaware corporation ("Grantor") and
U.S. Bank National Association, in its capacity as collateral agent for the
Initial Purchasers and all other Holders of the Securities (together with its
successors and assigns in such capacity, the "Collateral Agent").

                             PRELIMINARY STATEMENTS

            WHEREAS, Grantor is a party to a Security Agreement dated as of even
date herewith (as amended, restated or otherwise modified from time to time, the
"Security Agreement") between Grantor and the other grantors party thereto and
the Collateral Agent, as well as certain other Transaction Documents as
described in that certain Note and Warrant Purchase Agreement dated as of even
date herewith (as amended, restated or otherwise modified from time to time, the
"Note and Warrant Purchase Agreement") by and among Company, the investors
listed on the signature pages thereto and the Collateral Agent pursuant to which
Grantor is required to execute and deliver the Security Agreement and this
Patent Security Agreement.

            NOW, THEREFORE, in consideration of the promises contained therein
and to induce the Initial Purchasers to enter into the Transaction Documents,
Grantor hereby agrees with the Collateral Agent, as follows:

            Section 1. Defined Terms. Unless otherwise defined herein, terms
defined in the Security Agreement and used herein have the meaning given to them
in the Security Agreement.

            Section 2. Grant of Security Interest in Patent Collateral. Grantor
hereby pledges and grants to Collateral Agent, for the benefit of the Initial
Purchasers and Holders of the Securities, a security interest in all of
Grantor's right, title and interest in, to and under the following, whether
presently existing or hereafter created or acquired (collectively, the "Patent
Collateral"):

            (a) all United States and foreign patents and certificates of
invention, or similar industrial property rights, and applications for any of
the foregoing (collectively, "Patents"), including, but not limited to: (i) each
patent and patent application referred to on Schedule I hereto (as such schedule
may be amended or supplemented from time to time), (ii) all reissues, divisions,
continuations, continuations-in-part, extensions, renewals, and reexaminations
thereof, (iii) all rights corresponding thereto throughout the world, (iv) all
inventions and improvements described therein, (v) all rights to sue for past,
present and future infringements thereof, (vi) all licenses, claims, damages,
and proceeds of suit arising therefrom, and (vii) all Proceeds of the foregoing,
including,

                                       1
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without limitation, licenses, royalties, income, payments, claims, damages, and
proceeds of suit.

            (b) all agreements providing for the granting of any right in or to
Patents (whether Grantor is licensee or licensor thereunder) including those
referred to on Schedule I hereto (collectively, "Patent Licenses");

            (c) all reissues, divisions, continuations, continuations-in-part,
extensions, renewals, and reexaminations thereof;

            (d) all rights corresponding thereto throughout the world;

            (e) all inventions and improvements described therein;

            (f) all rights to sue for past, present and future infringements
thereof;

            (g) all licenses, claims, damages, and proceeds of suit arising
therefrom; and

            (h) all Proceeds of the foregoing, including, without limitation,
licenses, royalties, income, payments, claims, damages, and proceeds of suit.

            Section 3. Security Agreement. The security interest granted
pursuant to this Patent Security Agreement is granted in conjunction with the
security interest granted to the Collateral Agent for the Initial Purchasers and
Holders of the Securities pursuant to the Security Agreement and Grantor hereby
acknowledges and affirms that the rights and remedies of the Collateral Agent
with respect to the security interest in the Patents made and granted hereby are
more fully set forth in the Security Agreement and the other Transaction
Documents, the terms and provisions of which are incorporated by reference
herein as if fully set forth herein. In the event that any provision of this
Patent Security Agreement is deemed to conflict with the Security Agreement, the
provisions of the Security Agreement shall control.

            Section 4. Applicable Law. This Patent Security Agreement and the
rights and obligations of the parties hereunder shall be governed by, and shall
be construed and enforced in accordance with, the laws of the State of New York,
without regard to its conflicts of law provisions (other than Section 5-1401 and
Section 5-1402 of the New York General Obligation Laws).

            Section 5. Counterparts. This Agreement may be executed in any
number of counterparts, each of which when so executed and delivered shall be
deemed an original, but all such counterparts together shall constitute but one
and the same instrument.

                  [Remainder of page intentionally left blank]

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            IN WITNESS WHEREOF, Grantor has caused this Patent Security
Agreement to be executed and delivered by its duly authorized officer as of the
date first set forth above.

                                     MEDIADEFENDER, INC., a Delaware corporation

                                     By: /s/ Octavio Herrera
                                         -----------------------------
                                         Name: Octavio Herrera
                                         Title: Secretary

                           [Patent Security Agreement]

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Accepted and Agreed:

U.S. BANK NATIONAL ASSOCIATION
as Collateral Agent

By: /s/ Brad E. Scarbrough
    --------------------------------
    Name: Brad E. Scarbrough
    Title: Vice President

                           [Patent Security Agreement]

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                                   SCHEDULE I
                                       TO
                            PATENT SECURITY AGREEMENT

                      PATENT REGISTRATIONS AND APPLICATIONS

<TABLE>
<CAPTION>
APPLICATION NO.   PATENT NO.                      TITLE                      OWNER
---------------   ----------   -------------------------------------   -------------------
<S>               <C>          <C>                                     <C>
  10/371,513       PENDING     COMPUTER NETWORK FILE SYNCHRONIZATION   MEDIADEFENDER, INC.
                                         SYSTEM AND METHOD
</TABLE>