COLLATERAL GRANT OF SECURITY INTEREST IN COPYRIGHTS
Execution
      Version
    This
      Collateral Grant of Security Interest in Copyrights (this “Agreement”)
      is
      made as of this 28th day of September, 2007, by each of Diomed Holdings, Inc.,
      a
      Delaware corporation, and Diomed, Inc., a Delaware corporation (each a
“Grantor”,
      and
      collectively, the “Grantors”),
      for
      the benefit of Hercules Technology Growth Capital, Inc., a Maryland corporation
      (“Grantee”).
    WHEREAS,
      Grantors own an interest in Copyrights (as defined in the Loan Agreement (as
      defined below)) and are, whether individually or collectively, party to
      Copyright Licenses to which it is a party (as defined in the Loan Agreement)
      listed on Schedule
      I;
      and
    WHEREAS,
      pursuant to that certain Loan and Security Agreement dated as of September
      28,
      2007, and related Notes (as defined therein) (collectively, the “Loan
      Agreement”),
      each
      Grantor has granted to Grantee a security interest in all of such Grantor’s
      assets, including all right, title and interest of such Grantor in, to and
      under
      all of such Grantor’s Copyrights and Copyright Licenses to which it is a party,
      all renewals thereof, in each case whether presently existing or hereafter
      arising or acquired, to secure the payment of all the Secured Obligations (as
      defined in the Loan Agreement). All capitalized terms and rules of construction
      used herein but not defined or established herein shall be applied herein as
      defined or established in the Loan Agreement.
    NOW,
      THEREFORE, for good and valuable consideration, the receipt and sufficiency
      of
      which are hereby acknowledged, Grantors agree as follows:
    1.
       Grant
      of Security Interest in Copyright Collateral.
      To
      secure the prompt and complete payment, performance and observance of the
      Secured Obligations, each Grantor hereby reaffirms its grant of, and further
      grants to Grantee a continuing security interest in all of such Grantor’s now
      existing or hereafter acquired right, title and interest in, to and under the
      following (all of the following items or types of property being herein
      collectively referred to as the “Copyright
      Collateral”),
      whether now existing or hereafter arising:
    a.
       all
      Copyrights and Copyright Licenses to which it is a party including those
      Copyrights listed on Schedule
      I;
      and
    b.
       all
      Proceeds of the foregoing.
    2.
       Authorization.
      Should
      any Grantor register any Copyrights, such Grantor (i) shall promptly notify
      Grantee of such registration and (ii) hereby authorize Grantee to file this
      Agreement with the U.S. Copyright Office and take any other actions necessary
      to
      perfect Grantee’s security interest in the Copyright Collateral. Each Grantor
      hereby authorizes and requests that the U.S. Copyright Office, Library of
      Congress record this Agreement and the interests herein granted.
    3.
       Security
      for Obligations.
      The
      security interest in the Copyright Collateral is granted to secure the Secured
      Obligations under and pursuant to the Loan Agreement. Each Grantor does hereby
      further acknowledge and affirm that the rights and remedies of Grantee with
      respect to the security interest in the Copyright 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.
    4. Maintenance
      of Schedule.
      Each
      Grantor authorizes Grantee to unilaterally modify this Agreement by amending
      Schedule
      I
      to
      include any future Copyrights and Copyrights Licenses which are Copyrights
      and
      Copyright Licenses under paragraph
      1
      hereof.
    5.
       Governing
      Law.
      This
      Agreement shall be deemed made and accepted in and shall be governed by and
      construed in accordance with the laws of the State of California without regard
      to the conflicts of law principles hereof, and (where applicable) the laws
      of
      the United States of America.
    6.
       Further
      Assurances.
      At any
      time and from time to time, upon the written request of Grantee, and at the
      sole
      expense of Grantors, each Grantor will promptly and duly execute and deliver
      such further instruments and documents and take such further action as Grantee
      may reasonably request for the purpose of obtaining or preserving the full
      benefits of this Agreement and the Loan Agreement, and of the rights and powers
      herein and therein granted, including, without limitation, the filing of any
      additional, supplemental, or amended Collateral
      Grant of Security Interest in Copyrights
      with the
      U.S. Copyright Office, or the filing of any financing statements or continuation
      statements under the Uniform Commercial Code in effect in any jurisdiction
      with
      respect to the Liens created hereby or in any of the Loan
      Agreement.
    7.
       Grantee’s
      Right to ▇▇▇.
      From
      and after the occurrence and during the continuance of an Event of Default,
      subject to the terms of the Loan Agreement, Grantee shall have the right, but
      shall in no way be obligated, to bring suit in its own name against any third
      parties to enforce Grantee’s interests in and to the Copyright Collateral, and,
      if Grantee shall commence any such suit, Grantors shall, at the request of
      Grantee, do any and all lawful acts and execute and deliver any and all proper
      documents, instruments or information that may be necessary or desirable to
      aid
      Grantee in such enforcement and Grantors shall promptly, upon demand, reimburse
      and indemnify Grantee for all costs and expenses, including reasonable
      attorneys’ fees, incurred by Grantee in the exercise of the foregoing rights.
      Any recovery from such suits shall be applied by Grantee in the order or
      priorities set forth in the Loan Agreement.
    8.
       Modification.
      Except
      as set forth in paragraph
      4
      hereof,
      this Agreement cannot be altered, amended or modified in any way, except as
      specifically provided by a writing signed by Grantors and Grantee.
    9.
       Binding
      Effect.
      This
      Agreement shall be binding upon Grantors and their respective successors and
      assigns, and shall inure to the benefit of Grantee, its nominees and
      assigns.
    10. Notice.
      Section
      11.2 (Notice)
      of the
      Loan Agreement is hereby incorporated herein in its entirety, save that
      references therein to the term Lender shall be deemed to be references to
      Grantee herein and references therein to the term Borrower shall be deemed
      to be
      references to Grantors herein.
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      of Page Intentionally Left Blank]
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        IN
      WITNESS WHEREOF,
      the
      parties have duly executed this Collateral Grant of Security Interest in
      Copyrights as of the date first set forth above. 
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               DIOMED
                HOLDINGS, INC. 
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               By: 
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               Name: 
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               Title: 
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               DIOMED,
                INC. 
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               By: 
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               Name: 
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               Title: 
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               By: 
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               ▇.
                ▇▇▇▇▇▇▇▇ Martitsch 
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               Its:
                 
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               Associate
                General Counsel 
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        SCHEDULE
      I
    BY
      DIOMED HOLDINGS, INC. AND DIOMED, INC. IN FAVOR OF HERCULES
TECHNOLOGY GROWTH CAPITAL, INC.
    TECHNOLOGY GROWTH CAPITAL, INC.
COPYRIGHT
      REGISTRATIONS, APPLICATIONS AND LICENSES
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                 Copyright
                  Title 
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                 Copyright
                  No. 
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                 Registration
                  Date 
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                 NONE 
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