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                                                                   EXHIBIT 10.36

                                   PATENT AND
                          TRADEMARK SECURITY AGREEMENT

         THIS PATENT AND TRADEMARK SECURITY AGREEMENT, effective as of December
4, 2003, by and between PROXYMED, INC., a Florida corporation, ("PROXYMED"), KEY
COMMUNICATIONS SERVICE, INC., an Indiana corporation ("KEY COMMUNICATIONS"), and
MEDUNITE, INC., a Delaware corporation ("MEDUNITE"; and together with Proxymed
and Key Communications, collectively, the "GRANTORS" and each individually, a
"GRANTOR"), in favor of WACHOVIA BANK, NATIONAL ASSOCIATION, a national banking
association ("LENDER").

                              W I T N E S S E T H:

         WHEREAS, pursuant to that certain Loan and Security Agreement, dated as
of December 4, 2003 by and among Grantors, as the Borrowers and Lender
(including all annexes, exhibits or schedules thereto, and as from time to time
amended, restated, supplemented or otherwise modified, the "LOAN AGREEMENT"),
Lender has agreed to make certain loans and other financial accommodations for
the benefit of Grantors;

         WHEREAS, pursuant to the Loan Agreement, Grantors are required to
execute and deliver to Lender, this Patent and Trademark Security Agreement;

         NOW, THEREFORE, in consideration of the premises and mutual covenants
herein contained and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, each Grantor hereby agrees as
follows:

         1. DEFINED TERMS. All capitalized terms used but not otherwise defined
herein have the meanings given to them in the Loan Agreement.

         2. GRANT OF SECURITY INTEREST IN PATENT COLLATERAL. Each Grantor hereby
grants to Lender a continuing first priority security interest in all of such
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 of its patents, patent applications and patent licenses
                  (and income and royalties with respect thereto) to which it is
                  a party including those referred to on SCHEDULE 1 hereto;

         (b)      all reissues, divisions, continuations, continuations-in-part,
                  renewals or extensions of the foregoing; and

         (c)      all products and proceeds of the foregoing, including, without
                  limitation, any claim by such Grantor against third parties
                  for past, present or future infringement or dilution of any
                  patent or any patent licensed under any patent license.



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         3. GRANT OF SECURITY INTEREST IN TRADEMARK COLLATERAL. Each Grantor
hereby grants to Lender, a continuing first priority security interest in all of
such Grantor's right, title and interest in, to and under the following, whether
presently existing or hereafter created or acquired (collectively, the
"TRADEMARK COLLATERAL"):

         (a)      all trademarks, service marks and trade names (collectively,
                  the "TRADEMARKS") whether registered or unregistered and
                  wherever registered (and any applications therefor) and
                  trademark licenses (the "TRADEMARK LICENSES") to which it is a
                  party including those referred to on SCHEDULE 2 hereto;

         (b)      all reissues, renewals, continuations or extensions of the
                  foregoing;

         (c)      all goodwill of the business connected with the use of, and
                  symbolized by, each Trademark and each Trademark License; and

         (d)      all products and proceeds of the foregoing, including, without
                  limitation, any claim by such Grantor against third parties
                  for past, present or future (i) infringement or dilution of
                  any Trademark or Trademark licensed under any Trademark
                  License or (ii) injury to the goodwill associated with any
                  Trademark or any Trademark licensed under any Trademark
                  license.

         4. RIGHTS AND REMEDIES.

         (a)      The security interests granted pursuant to this Patent and
                  Trademark Security Agreement are granted in conjunction with
                  the security interests granted to Lender, pursuant to the Loan
                  Agreement. Each Grantor hereby acknowledges and affirms that
                  the rights and remedies of Lender with respect to the security
                  interest in the Patent Collateral and Trademark Collateral
                  made and granted hereby are more fully set forth in the Loan
                  Agreement, the terms and provisions of which are incorporated
                  by reference herein as if fully set forth herein.

         (b)      Notwithstanding anything to the contrary herein or in any of
                  the other Loan Documents, if any Default or Event of Default
                  under the Loan Agreement or any other Loan Document shall have
                  occurred, or if any Grantor fails to perform any agreement or
                  to meet any of the obligations to the Lender hereunder, in
                  addition to any and all other rights and remedies that Lender
                  may have in the Loan Agreement, in any other Loan Document or
                  at law, all of the right, title and interest of Grantors in
                  and to the Patent Collateral and the Trademark Collateral
                  shall be automatically granted, assigned, conveyed and
                  delivered to the Lender or its designee, and Grantors hereby
                  irrevocably constitute and appoint Lender and any officer,
                  agent or employee thereof, with full power of substitution, as
                  their true and lawful attorney-in-fact, with full irrevocable
                  power and authority in the place and stead of Grantors and in
                  the name of Grantors or in Lender's own name or the name of
                  Lender's designee, all acts of said



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                  attorney being hereby ratified and confirmed, except to the
                  extent any of the same constitute gross negligence or willful
                  misconduct, such power being coupled with an interest is
                  irrevocable, upon the occurrence of a Default or an Event of
                  Default: (i) to complete, date, execute and file or cause to
                  be filed the Assignment attached hereto as EXHIBIT A and
                  incorporated hereby by reference (the "ASSIGNMENT") in the
                  United States Patent and Trademark Office and in all other
                  applicable offices, and to execute and deliver any and all
                  documents and instruments which may be necessary or desirable
                  to accomplish the purpose of the Assignment; (ii) to collect
                  proceeds from the Patent Collateral and the Trademark
                  Collateral (including, by way of example, license royalties
                  and proceeds of infringement suits); (iii) to convey in any
                  transaction authorized by the Loan Agreement, any goods
                  covered by the registrations listed on SCHEDULE 1 and SCHEDULE
                  2 to any purchaser thereof; (iv) to make payment or discharge
                  taxes or liens levied or placed upon or threatened against any
                  goods covered by the registrations listed on SCHEDULE 1 and
                  SCHEDULE 2, the legality or validity thereof and the amounts
                  necessary to discharge the same to be determined by Lender, in
                  its sole discretion, and such payments made by Lender to
                  become the obligations of Grantors to Lender, due and payable
                  immediately, without demand.

                            [SIGNATURE PAGES FOLLOW]




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


                                   GRANTORS

                                   PROXYMED, INC.


                                   By: /s/ Nancy J. Ham
                                       -----------------------------------------
                                   Name: Nancy J. Ham
                                   Title: President and Chief Operating Officer

                                   KEY COMMUNICATIONS SERVICE, INC.


                                   By: /s/ Nancy J. Ham
                                       -----------------------------------------
                                   Name: Nancy J. Ham
                                   Name: NANCY J. HAM
                                   Title: Chief Executive Officer

                                   MEDUNITE, INC.


                                   By: /s/ Nancy J. Ham
                                       -----------------------------------------
                                   Name: Nancy J. Ham
                                   Title: President



ACCEPTED AND ACKNOWLEDGED BY:
WACHOVIA BANK, NATIONAL ASSOCIATION,
as Lender


By: /s/ Joe Lee
    ---------------------------------
Name: Joe Lee
Title: Associate





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