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                                                                    Exhibit 10.4

                            NEGATIVE PLEDGE AGREEMENT

         This Negative Pledge Agreement is made as of November 4, 2002, by and
between Animas Corporation and Animas Diabetes Care, LLC (collectively, the
"Borrowers") and Silicon Valley Bank ("Bank").

         In connection with, among other documents, the Loan and Security
Agreement (the "Loan Agreement") of even date herewith by and among the
Borrowers and Bank, and the Loan Documents defined therein being concurrently
executed herewith between Borrowers and Bank, Borrower agrees as follows:

         1.       Except as permitted under Section 7.1 of the Loan Agreement,
                  Borrower shall not sell, transfer, assign, mortgage, pledge,
                  lease, grant a security interest in, or encumber, or enter
                  into any agreement, document, instrument or other arrangement
                  (except with or in favor of the Bank) with any Person which
                  directly or indirectly prohibits or has the effect of
                  prohibiting Borrower from selling, transferring, assigning,
                  mortgaging, pledging, leasing, granting a security interest in
                  or upon, or encumbering any of Borrower's intellectual
                  property related to any joint venture agreement between any
                  Borrower and any third party related to Glucose Sensor or
                  Glucose Monitor technology developed under the National
                  Institute of Standards and Technology (NIST) Cooperative
                  Agreement, including, without limitation, that certain Joint
                  Venture Agreement by and between Borrower and Sarnoff
                  Corporation dated July 31, 2001 including, without limitation,
                  the following:

                  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                           whether published or unpublished and whether or not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;

                  b.       All mask works or similar rights available for the
                           protection of semiconductor chips, now owned or
                           hereafter acquired;

                  c.       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;

                  d.       Any and all design rights which may be available to
                           Borrower now or hereafter existing, created, acquired
                           or held;

                  e.       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;

                  f.       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 Borrower
                           connected with and symbolized by such trademarks;

                  g.       Any and all claims for damages by way of past,
                           present and future infringements 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;

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                                                                    Exhibit 10.4

                  h.       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

                  i.       All amendments, extensions, renewals and extensions
                           of any of the Copyrights, Trademarks or Patents; and

                  j.       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.       It shall be an event of default under the Loan Documents
                  between Borrower and Bank if there is a breach of any term of
                  this Negative Pledge Agreement.

         3.       Capitalized terms used but not otherwise defined herein shall
                  have the same meaning as in the Loan Documents.

BORROWERS:

ANIMAS CORPORATION

By: /s/ Richard A. Baron
    ------------------------
Name: Richard A. Baron

Title:  V.P. Finance

ANIMAS DIABETES CARE, LLC

By: /s/ Richard A. Baron
    ------------------------
Name: Richard A. Baron

Title:  V.P. Finance

BANK:

SILICON VALLEY BANK

By: /s/ Elizabeth A. Harper
    ------------------------
Name: Elizabeth A. Harper

Title:  Senior Vice President