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                                                                   Exhibit 10.21

                         Marketing Cooperation Agreement


1.       Parties. This marketing co-operation agreement is entered into as of
         the date of final execution hereof, by and between OCEAN POWER
         TECHNOLOGIES, INC., a corporation organized and existing under the laws
         of New Jersey, having its principal place of business at 1590 Reed
         Road, Pennington, NJ 08534 (hereinafter referred to as "OPT") and
         LOCKHEED MARTIN CORPORATION, a corporation organized and existing under
         the laws of the State of Maryland, USA, acting through its Maritime
         Systems and Sensors business unit, and having a place of business at
         9500 Godwin Drive, Manassas, Virginia 20110-4157 (hereinafter referred
         to as "LM MS2"); the above parties may also be variously referred to as
         a "Party" or collectively as "Parties". The understandings arising
         hereunder shall apply only to the LM MS2 business unit and not to any
         other business unit, sector, group, division, subsidiary or affiliate
         of Lockheed Martin Corporation.

2.       Purpose. The purpose of this document is to establish non-binding
         guidelines under which the parties will identify opportunities in which
         they may co-operatively market OPT's wave energy conversion technology
         for the mutual benefit of LM MS2 and OPT.

3.       Basis. OPT and LM MS2 are currently working together on an SBIR project
         for the Department of Homeland Security. In this project OPT's wave
         energy conversion buoy houses and powers LM MS2 sensors to provide
         coastal surveillance of merchant vessels. OPT and LM MS2 have mutual
         interest in the pursuit of potential opportunities in Autonomous
         Maritime Sensing, Ocean Observation, and Autonomous Underwater Vehicle
         support for both Department of Defense and commercial customers. OPT
         has unique and extensive experience, knowledge and expertise in design,
         development, and support of wave energy conversion buoy technology. LM
         MS2 has extensive experience, knowledge, and expertise in sensor
         systems, underwater vehicles, systems engineering and integration, and
         program management.

4.       Co-operative Marketing. Considering that the complimentary capabilities
         of the Parties can be expected to enhance their abilities to meet
         customer requirements, LM MS2 and OPT agree to work co-operatively to:

         a.       Monitor Autonomous Maritime Sensing, Ocean Observation,
                  Autonomous Underwater Vehicle and related programs for
                  business opportunities of joint interest.

         b.       Identify additional opportunities which could cost-effectively
                  be addressed using OPT's wave energy conversion technology and
                  LM MS2 capabilities.

         c.       Determine together if, and how, LM MS2 and OPT should jointly
                  pursue such opportunities.

5.       Relationship of the Companies. LM MS2 and OPT shall at all times act as
         independent contractors in the activities contemplated hereunder.
         Neither party shall represent the other without prior written
         permission. Each Party shall bear its own cost, expenses, risks, and
         liabilities in connection with such activities.


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         Neither Party is under any obligation by virtue of this Agreement,
         except to discuss in good faith potential opportunities and to work
         together to market OPT's wave energy conversion technology. Once the
         parties jointly agree to pursue a specific marketing opportunity, both
         parties shall enter into a separate written agreement specifying what
         marketing and/or other resources each party will commit to the
         opportunity over a specified period of time. Additionally, the parties
         may mutually elect to enter separate teaming agreements to address
         opportunities of mutual interest.

6.       Termination. This co-operative marketing agreement shall terminate and
         have no further effect upon occurrence of any of the following events:

         a.       Thirty (30) days written notice by either Party.

         b.       Expiration of three (3) years from the date of signing this
                  document.

7.       Entire Agreement. This agreement constitutes the sole and entire
         understanding and agreement of the Parties, superseding all prior
         representations relating to the subject matter hereof.

8.       Points of Contact. The points of contact for the parties are as
         follows:


         LM MS2 -  Judy Dawson
                   9500 Godwin Drive
                   Manassas, VA 20110
                   Tel: 703-367-1486
                   Email: judy.dawson@imco.com

         OPT -     Deborah A. Montagna
                   1590 Reed Road
                   Pennington, NJ 08534
                   Tel: 609-730-0400 x-221
                   Email: dmontagna@oceanpowertech.com


                 LM MS2                                  OPT
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BY     /s/ [ILLEGIBLE]                BY:    /s/ GEORGE W. TAYLOR
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                                             George W. Taylor

TITLE: V.P. Business Development      TITLE: CEO
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DATE:  9/19/2006                      DATE:  Sept 13, '06
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