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                                                                    Exhibit 10.1
                                  CONFIDENTIAL

                           IMPAC MEDICAL SYSTEMS, INC.

                         SOFTWARE DISTRIBUTION AGREEMENT

     This Software Distribution Agreement (this Agreement) is entered into
between IMPAC Medical Systems, Inc., a California corporation (IMPAC), and
Siemens Medical Systems, Inc., a Delaware corporation (Siemens).

                                   Background

         IMPAC owns or has rights to various software products relating to
healthcare information and data management. Siemens is in the business of
distributing software products to its customers. The parties desire that Siemens
sublicense and distribute certain of IMPAC's products to Siemens' customers in
accordance with the provisions of this Agreement.

         Therefore the parties agree as follows:

1.  Definitions.

    1.1  "Affiliate" means any business entity directly or indirectly
         controlling, under common control with, or controlled by either party
         to this Agreement or any third party identified herein. For purposes of
         the foregoing, "control" shall include the right, directly or
         indirectly, to direct the management of an entity by ownership of more
         than fifty percent (50%) of the voting stock (or its equivalent)
         entitled to determine or remove the board of directors (or their
         equivalent).

    1.2  "Alpha," "Alpha Product," "Alpha Release" means a Product in that stage
         of the product lifecycle that applies to new products undergoing
         software prototype evaluation by one or more IMPAC customers or
         End-Users for a finite period of time prior to formal release for the
         purpose of providing user validation of requirements. Alpha Releases
         shall only be used non-clinically, ***.

    1.3. "Beta," "Beta Product," "Beta Release" means a Product in that stage of
         the product lifecycle that applies to new products or *** existing
         products, not necessarily feature-complete, that are placed in limited
         distribution to select sites for a finite period of time for the
         purpose of testing, feedback, and revision, with the expectation that
         feedback from the End-Users shall be used to ensure the product meets
         specified requirements and functions as intended. A Beta Release may be
         used ***. Furthermore, all Beta Releases must be provided to End-Users
         subject to End-User Agreements.***.

    1.4  "Confidential Information" means all confidential or proprietary
         (written, recorded or oral) information or data (a) marked or
         identified by the disclosing party as being confidential or proprietary
         or (b) that the receiving party should reasonably understand to be
         confidential or proprietary. By way of example and not limitation,
         Confidential Information may include research, developmental,
         engineering, manufacturing, technical, marketing, sales, financial,
         operating, performance, cost,

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                                  CONFIDENTIAL

              business and process information or data, know-how, and computer
              programming and other software and software techniques.

   1.5.       "Discloser" means a party disclosing Confidential Information to
              the other party under this Agreement and pursuant to and subject
              to the provisions of Section 14 of this Agreement.

   1.6.       "Documentation" means End-User manuals, product descriptions,
              product specification sheets ***, and other written materials that
              relate to one or more of the Products. Documentation shall include
              these written materials with respect to Maintenance Modifications,
              upgrades, updates, and Enhancements if, when, and to the extent
              delivered to Siemens by IMPAC under, or in connection with, this
              Agreement.

   1.7.       "Effective Date" means the date on which the last party to sign
              this Agreement does so.

   1.8.       "End-User" means a person or entity who licenses one or more of
              the Products for internal use only, and not for further
              redistribution.

   1.9        "End-User Agreement" means an agreement substantially in the form
              of, and containing terms no less protective than, the agreement
              attached to this Agreement as Exhibit B, under which End Users are
              granted a license to use the Products.

   1.10       "Enhancement" means an individually controlled or registered
              modification, addition, or substitution by IMPAC generally made
              available to IMPAC's customers from time to time, other than a
              Maintenance Modification, that accomplishes one or more
              performance, structural, or functional improvements to Products.

   1.11       "IMPAC Marks" means without limitation all trademarks, service
              marks, trade names, and trade dress owned or licensed by IMPAC.

   1.12       "Inspection Period" means that number of days or period of time
              designated in subsection 5.3 of this Agreement during which
              Siemens may inspect and test the Products, and determine and
              effectively communicate, pursuant to the provisions of subsection
              5.3, whether Siemens accepts or rejects any Product unit.

   1.13       "Intellectual Property Rights" means all worldwide intellectual
              property rights, including, but not limited to, patents,
              copyrights, authors' rights, trademarks, trade names, know-how,
              and trade secrets, irrespective of whether these rights arise
              under U.S., foreign, or international intellectual property,
              unfair competition, or trade secret laws.

   1.14       "Interface Products" means those Siemens software and hardware
              products that enable Siemens' radiotherapy treatment machines and
              simulators to interface with other products.

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   1.15       "Maintenance Modification" means a modification, update, or
              revision by IMPAC generally made available in IMPAC's sole
              discretion to IMPAC's customers from time to time that corrects
              errors or responds to routine maintenance or support requirements
              of Products. Maintenance Modifications may include without
              limitation modifications, updates, or revisions made to support
              industry-standard changes in supported operating systems, and to
              comply with regulatory requirements.

   1.16       "Maintenance Period" means that number of years or other time
              period *** during which IMPAC shall be obligated, pursuant to the
              provisions of subsection 9.1 to provide continuing support of the
              Products.

   1.17       "Object Code" means executable computer programming code in
              machine-readable form generated by compilation, assembly, and
              linking of Source Code, together with machine-readable program and
              data files, and contained in a medium that permits it to be loaded
              and operated on a computer system. Object Code shall not be
              construed to encompass customer or End-User generated data.

   1.18       "Pilot," "Pilot Product," "Pilot Release" means Products in that
              period of the product lifecycle that applies to products with new
              feature additions or enhancements that are placed in controlled or
              conditional customer distribution for a finite period of time ***.

   1.19       "Production," "Production Product," "Production Release" means a
              product in that stage of the product lifecycle that applies to
              products released for distribution to End-Users pursuant to the
              provisions of the End-User Agreement, and that does not constitute
              an Alpha, Beta, or Pilot Product.

   1.20       "Products" means the software products proprietary to IMPAC, its
              licensors, or both, that are permitted to be distributed by
              Siemens under this Agreement, as set forth on Exhibit A, as
              modified and added to from time to time upon mutual agreement of
              the parties. Products shall also include all updates, upgrades,
              Enhancements, and Maintenance Modifications to the Products
              completed pursuant to this Agreement, and any accompanying related
              Documentation.

   1.21       "Purchase Order" means an order that shall include customer name
              and location, ***, sales order number, software part numbers,
              software descriptions, quantity, unit price, total order amount,
              and the products and equipment, if any, with which the Products
              will be distributed.

   1.22       "Radiation Oncology Distributor" means a business entity that
              derives *** from the sale of radiation therapy specific products
              and services to end-users.

   1.23       "Recipient" means a party receiving Confidential Information from
              the other party under this Agreement and pursuant to and subject
              to the provisions of Section 14 of this Agreement.

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   1.24       "RMA" means returned material authorization used with and governed
              by the inspection and acceptance provisions of subsection 5.3.

   1.25       "Siemens Marks" means all trademarks, service marks, trade names,
              and trade dress owned or licensed by Siemens.

   1.26       "Source Code" means computer programming code in human-readable
              programming language together with all comments and procedural
              code such as job control language statements and all related
              development documents such as flow charts, schematics, statements
              of principles of operations, architectural standards and other
              specifications that are used to create the relevant software.

   1.27       "Subdistributor" means those third parties that act as
              subdistributors of the Products through Siemens pursuant to the
              provisions of subsection 2.4.

   1.28       "Support Year" means that year-long time period measured from
              October 1 to September 30.

   1.29       "Termination Date" means the effective date of termination or
              expiration of this Agreement.

   1.30       "Territory" means that territory within which Siemens, its
              Affiliates, and its Subdistributors are permitted to distribute
              the Products. For purposes of this Agreement, the Territory shall
              be worldwide.

   1.31       "VMI/Siemens Software" means ***.

2. Distribution Generally.

   2.1        Non-Exclusive Appointment. Subject to the licenses and
              restrictions set forth in this Agreement, IMPAC appoints Siemens
              as a non-exclusive distributor of the Products to End-Users within
              the Territory.

   2.2        Marketing and Promotional Efforts. Siemens shall use commercially
              reasonable efforts to market, promote, and distribute the
              Products. These efforts may include without limitation the use of
              mailings, telemarketing programs, advertising, seminars, and other
              customary marketing techniques.

   2.3        Affiliates. Siemens shall be entitled to distribute the Products
              through Siemens' Affiliates; provided, however, that each
              Affiliate acknowledges, adheres to, and does not perform any act
              inconsistent with, the terms and conditions of this Agreement, and
              provided further that Siemens shall remain responsible for the
              full compliance by each Affiliate with the provisions of this
              Agreement. Siemens shall ensure that all Affiliates cease
              distribution of Products upon termination of Siemens' rights to do
              so hereunder. ***

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   2.4        Subdistributors. Siemens shall be entitled to distribute the
              Products through those Subdistributors engaged to so distribute
              the Products as of the Effective Date of this Agreement; provided,
              however, that Siemens shall ensure that each Subdistributor
              acknowledges, adheres to, and does not perform any act
              inconsistent with, the terms and conditions of this Agreement, and
              provided further that Siemens shall remain responsible for the
              full compliance by each Subdistributor with the provisions of this
              Agreement. Siemens shall ensure that all Subdistributors cease
              distribution of Products upon termination of Siemens' rights to do
              so hereunder. ***

   2.5        Labeling. In the event that Siemens markets or distributes any
              Product under any Siemens Mark, name or logo, other than those
              authorized for use with the Product as set forth in Exhibit A,
              Siemens shall not use or display any IMPAC Mark in connection with
              the Product without IMPAC's prior written approval.

   2.6        Feedback by Siemens. Siemens shall use commercially reasonable
              efforts to provide IMPAC with prompt written notification of
              any comments or complaints about the Products that are made by
              End Users, and ***.

3. Pricing and Payment.

   3.1        Pricing. Beginning on the Effective Date and continuing through
              September 30, 2001, the pricing of the Products shall remain at
              those prices delineated pursuant to that certain Software
              Development and OEM License Agreement between the parties, dated
              as of October 1, 1992, as subsequently amended. Thereafter, IMPAC
              shall supply Products and training to Siemens at prices in
              accordance with the price list set forth in Exhibit A. Unless
              otherwise set forth therein, the prices in Exhibit A shall remain
              in effect for a period beginning October 1, 2001 and extending for
              ***. Thereafter IMPAC may modify the prices in its discretion no
              more frequently than ***.

   3.2        ***.

              3.2.1   ***.

              3.2.2.  Distribution Rights to New Radiation Oncology Products.
                      Subject to the terms of this Agreement, ***, Siemens shall
                      be entitled to distribute all those new products developed
                      by IMPAC the primary functionality of which specifically
                      addresses the planning, verification, or delivery of
                      radiation treatments, ***.

   3.3        Payment. Siemens shall pay for Products supplied hereunder within
              *** following Siemens' receipt of the Products and IMPAC's invoice
              thereof in accordance with this Agreement. Any payments due from
              Siemens hereunder which are not paid by Siemens within *** after
              becoming due and payable shall incur a late charge ***.

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                                  CONFIDENTIAL

4. Forecasts, Orders, and Delivery of Products

   4.1        Forecasts. During the term of this Agreement, Siemens shall
              provide IMPAC with a good faith rolling twelve (12) month
              forecast, updated quarterly, for units of the Products requested
              to be provided by IMPAC to Siemens hereunder during each month in
              this twelve (12) month period.

   4.2        Orders. All Product orders placed by Siemens shall be accompanied
              by ***. In the event of any conflict or inconsistency between the
              terms and conditions of any Purchase Order and this Agreement, the
              terms and conditions of this Agreement shall prevail.

              4.2.1   Order Processing. Upon receipt by IMPAC of *** sent by
                      Siemens, IMPAC shall verify the order, *** and return to
                      Siemens *** the following ***. IMPAC shall exercise
                      commercially reasonable efforts to complete the order
                      processing within *** of receipt of an accurate and
                      complete *** from Siemens. Notwithstanding the foregoing
                      sentence, the parties agree to work together to limit the
                      time for completion of order processing ***.

              4.2.2   Order Cancellation or Termination. In the event any
                      customer of Siemens cancels or terminates its order for or
                      agreement to obtain Products from Siemens ***. The
                      cancellation or termination procedures outlined in this
                      subsection 4.2.2 shall not apply to any third-party
                      products supplied by IMPAC to Siemens.

              4.2.3.  Order ***. In the event any customer of Siemens cancels or
                      terminates its order for or agreement to obtain Products
                      from Siemens, ***. If, ***, then on a case-by-case basis,
                      IMPAC shall review Siemens' request for an exception to
                      the *** process as set out in this subsection 4.2.3, and
                      if, in IMPAC's sole discretion, the exception is
                      warranted, then IMPAC may allow Siemens to ***.

   4.3        Product *** Delivery.

              4.3.1   *** Products. To facilitate Siemens' distribution of the
                      Products to its End-Users, IMPAC shall *** or by other
                      means specified from time to time by IMPAC in its sole
                      discretion.

              4.3.2   End-User ***. Subject to the terms of this Agreement, upon
                      receipt by IMPAC of *** required under section 4.2.1, and
                      otherwise as may be specified from time to time in IMPAC's
                      sole discretion, IMPAC shall transfer to Siemens ***.

5. Packing, Shipping and Returns.  For those products ***, the following
   provisions shall apply.

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    5.1  Packing and Documentation. Unless otherwise specified in the applicable
         Purchase Order, IMPAC shall use commercially reasonable efforts to pack
         all Products to be delivered hereunder: (a) to ensure safe arrival at
         their ultimate destination, (b) to secure the lowest transportation
         costs, and (c) to comply with requirements of the common carrier
         selected. Siemens' order numbers and symbols must be plainly marked on
         all invoices, packages, bills of lading and shipping orders. Shipping
         memos or packing lists must accompany all Products to be delivered
         hereunder, and bills of lading or shipping receipts must accompany each
         invoice. Siemens' count shall be final and conclusive on shipments not
         accompanied by shipping memos or packing lists. Shipments shall be
         routed in accordance with Siemens' instructions.

    5.2  Shipping and Risk of Loss. IMPAC shall ship Products ordered by Siemens
         within ***, unless a delayed shipment or delivery date is specified in
         the Purchase Order, in which case IMPAC shall ship Products for
         delivery as specified in the Purchase Order. Shipping shall be FOB
         IMPAC's facility (or, for shipments to be made outside of the United
         States, EXW IMPAC's facility per Incoterms 2000). Unless otherwise
         specified in the applicable Purchase Order, all freight charges shall
         be added to the invoices. Risk of loss of or damage to Products shall
         pass to Siemens at the time the Products leave the loading dock of
         IMPAC's facility.

    5.3  Inspection and Acceptance. Siemens' Inspection Period shall be ***
         after delivery of Product shipped by IMPAC to Siemens. If Siemens
         determines that any Product fails to meet the applicable Documentation
         in any material way, Siemens may reject the Product by notifying IMPAC
         in writing of the rejection and requesting a Returned Material
         Authorization ("RMA") number; provided, that the written notification
         and request for an RMA number must be received by IMPAC during the
         Inspection Period. IMPAC shall provide the RMA number within *** after
         its receipt of this request by Siemens. Within *** after receipt of the
         RMA number, Siemens shall return the defective units to IMPAC, insured
         and with transportation prepaid, in the same condition as at the time
         of delivery to Siemens, in the same or equivalent shipping container,
         and with a written description of the defect. If IMPAC confirms the
         defect, Siemens shall ***.

6. IMPAC Licenses, Restrictions and Ownership.

    6.1  End User Licenses. With respect to each copy of the Object Code for
         each Product provided to Siemens by IMPAC hereunder, and subject to the
         provisions of this Agreement, IMPAC hereby grants to Siemens a ***,
         non-exclusive, *** license to distribute the Object Code copy to an
         End-User within the Territory solely for the End-User's own internal
         use, and to permit the End-User to make one (1) back-up or archival
         copy of the Object Code. All sublicenses shall be made subject to the
         End-User Agreement. Upon execution of any End-User Agreement, Siemens
         shall *** in accordance with the *** procedures established, from time
         to time, by IMPAC. These *** procedures shall *** require Siemens to
         provide IMPAC with the applicable Purchase Order number, the name and
         address of the End-User, the Products and the corresponding number of
         seats licensed, if applicable. In the event

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                                  CONFIDENTIAL

         Siemens upgrades the operating system of any End-User for whom one or
         more Products were previously ***, which End-User desires to continue
         the sublicense under the same terms and conditions, Siemens shall ***.
         Siemens may sublicense its right hereunder to its Affiliates and
         Subdistributors, subject to all of the provisions and restrictions of
         this Agreement; provided, however, that Siemens shall remain
         responsible for the full compliance of each Affiliate and
         Subdistributor with the provisions of this Agreement.

    6.2  Limited *** License. Subject to the provisions of this Agreement, IMPAC
         hereby grants to Siemens a ***, worldwide, ***, and non-exclusive
         license, which, may be sublicensed to Affiliates and Subdistributors of
         Siemens only in accordance with the provisions of Section 2 of this
         Agreement, ***.

    6.3  Restrictions. Neither Siemens, nor any of its Affiliates or
         Subdistributors shall remove or obscure any proprietary notice in
         connection with any of the Products. Siemens and its Affiliates and
         Subdistributors shall reproduce and include those proprietary notices
         on any copies of the Products permitted under this Agreement. Except as
         expressly set forth in this Agreement, neither Siemens, nor any of its
         Affiliates or Subdistributors shall use, reproduce, distribute,
         sublicense, sell, encumber, modify or create derivative works of the
         Products in whole or in part. Neither Siemens, nor any of its
         Affiliates or Subdistributors shall copy, translate, disassemble,
         decompile, or otherwise attempt to discover the Source Code for the
         Products. Neither Siemens, nor any of its Affiliates or Subdistributors
         shall authorize any third party to take any action that Siemens is
         prohibited from taking under this subsection 6.3.

    6.4  Product Ownership. Siemens acknowledges and agrees that, except for the
         licenses expressly granted under this Agreement, IMPAC retains all
         right, title and interest in and to the Products, including without
         limitation all Intellectual Property Rights therein and the tangible
         medium in which the Products are embodied.

7. *** Further Agreements from Siemens.

    7.1  ***.

    7.2  ***.

8. Training.

    8.1  Continuing Training. IMPAC shall provide to Siemens instructors and
         materials for product and service training for all releases provided
         pursuant to this Agreement that IMPAC in its sole discretion designates
         as significant functional improvements. Releases subject to this
         training requirement generally shall include ***. The parties agree to
         exercise reasonable efforts to complete this training within ***. This
         training shall consist of *** of applications training and *** of sales
         and service

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                                  CONFIDENTIAL

         training ***. IMPAC shall provide this training at locations ***, at
         times mutually agreed upon by IMPAC and Siemens ***.

    8.2  Other Training. In the event Siemens desires IMPAC to provide any
         training in addition to that provided in Section 8.1, Siemens shall
         request this training in writing and IMPAC shall provide the training
         at the rates set forth in Exhibit A, at locations to be designated by
         Siemens and at times mutually agreed upon by IMPAC and Siemens (in
         their reasonable discretion). Travel, room and board expenses shall be
         borne and paid as provided in Section 8.1.

9. Support and Maintenance.

    9.1  Support Services. During the term of this Agreement, IMPAC shall supply
         support to Siemens for the Products as set forth in subsections 9.1.1
         and 9.1.2 below. In addition, for each individual Product for which
         Siemens provides its End-Users with support, IMPAC shall supply support
         for ***.

         9.1.1 Enhancements and Maintenance Modifications. IMPAC shall provide
               to Siemens *** Enhancements and Maintenance Modifications to the
               Products *** consistent with the testing, evaluation, and review
               provisions of section 11 of this Agreement.

         9.1.2 Telephone Support. IMPAC shall provide to Siemens reasonable
               levels of telephone support with respect to the Products between
               the hours of *** and *** Pacific Time, *** through ***, IMPAC
               holidays excepted.

         9.1.3 Investigative or Corrective Action. IMPAC shall initiate
               commercially reasonable investigative or corrective action to (1)
               rectify a *** discrepancy or *** discrepancy within *** of
               receipt by IMPAC of Siemens' written notice of the discrepancy;
               (2) rectify a *** discrepancy within *** of receipt by IMPAC of
               Siemens' written notice to IMPAC of the discrepancy; or (3)
               rectify a *** discrepancy within *** of receipt by IMPAC of
               Siemens' written notice of such discrepancy. Any written notices
               provided by Siemens under this section shall include a detailed
               description of such discrepancy, a description of the operating
               environment, and if known, the actions required to reproduce the
               discrepancy. The parties agree to work together in good faith to
               establish any necessary additional processes or procedures to
               further the intent of this section. The parties further agree to
               commence a review of current processes and procedures within
               ninety (90) days of the Effective Date of this Agreement.

    9.2  Support Fees. Within *** following the beginning of a Support Year as
         full consideration for the support provided during that Support Year,
         Siemens shall pay IMPAC the following amounts: ***.




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    9.3  *** Support. During the applicable Maintenance Period for each Product,
         IMPAC shall:


         9.3.1 supply patient safety related error correction releases for each
              Product to Siemens at no additional cost;

         9.3.2 offer to license to Siemens for sublicense to End-Users any
              Maintenance Modifications for each Product that IMPAC offers to
              IMPAC's End-Users at a price to be determined solely by IMPAC.
              ***. All sublicenses to Siemens's End-Users shall be subject to
              terms not less restrictive than those set forth in Exhibit B of
              the Agreement; and

         9.3.3 provide ongoing telephone support to Siemens's application and
              service personnel from *** to *** (PST), *** through ***, IMPAC
              holidays excepted.

    9.4. Failure to Pay. Except for IMPAC's obligations under subsection 9.3.1,
         IMPAC shall not be obligated to perform as set forth in subsections
         9.1, 9.2 or 9.3 above ***.

10.  Records and Audits. During the term of this Agreement and for a period of
     ***, Siemens shall maintain true and accurate books and records of all
     sublicenses made by it to End Users in sufficient detail to calculate the
     amounts due under this Agreement, for the *** immediately preceding the
     date of the audit. During the term of this Agreement and for a period of
     ***, at IMPAC'S request and sole expense, at mutually agreeable times, but
     not more frequently than ***, an accounting firm *** shall be provided
     reasonable access, during Siemens' normal business hours, to the books,
     records and employees of Siemens for purposes of auditing records of
     Products ordered from and shipped by Siemens and verification of Siemens'
     compliance with other obligations under this Agreement. The accounting firm
     conducting the audit shall be required to execute a written confidentiality
     agreement for the benefit of Siemens, substantially in the form attached to
     this Agreement as Exhibit D, prior to commencing the audit. The cost of any
     such audit shall be borne by IMPAC unless the audit reveals an aggregate
     underpayment by Siemens for the period being audited of greater than ***,
     in which case Siemens shall promptly reimburse IMPAC for the cost of the
     audit.

11.  Siemens Product Testing, Evaluation, and Review.

    11.1 Siemens shall, at IMPAC's discretion and at no charge, *** provide
         testing and evaluation information as requested by IMPAC with respect
         to any new Products and Enhancements developed during the term of this
         Agreement. Siemens shall treat all new Products, Enhancements, and
         descriptions and evaluations thereof as Confidential Information of
         IMPAC. In addition, IMPAC shall use commercially reasonable efforts to
         consider all proposals provided by Siemens in connection with the new
         Products and proposed Modifications and Enhancements to the Products,
         and shall provide reports to Siemens from time to time with respect to
         Siemens proposals. These proposals and reports shall constitute
         Confidential Information of IMPAC.

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    11.2 IMPAC shall grant Siemens access to ***. Use, testing, evaluation, and
         review by Siemens of those releases shall be in accordance with (a) the
         definitions of those releases as set forth in section 1 of this
         Agreement, (b) ***, and (c) *** other restrictions or guidelines
         established by IMPAC in its sole discretion. With each *** Release to
         which Siemens is granted access, IMPAC shall supply that Documentation
         available for that particular release of that product. If Siemens
         requests training for a release, it shall be conducted in accordance
         with the training provisions of this Agreement.

12. Source Code Escrow.

    12.1 During the term of this Agreement, IMPAC shall maintain a copy of the
         Source Code for the Products set forth in Appendix A and all
         documentation thereto (collectively, the "Escrowed Materials") with
         ***, pursuant to the Source Code Escrow Agreement between IMPAC and
         Siemens entered into on or about December 5, 2000, as it may be
         modified to reflect the terms set forth in this Agreement. In the event
         of a conflict between the Source Code Escrow Agreement and this section
         12, the Source Code Escrow Agreement shall govern. The Escrowed
         Materials shall be deemed Confidential Information and shall be subject
         to the confidentiality restrictions set forth in Section 14. IMPAC
         shall update the Escrowed Materials *** during the term of this
         Agreement. The escrow agreement shall continue until the expiration of
         the ***. Siemens shall bear all escrow fees incurred pursuant to this
         section. The parties acknowledge that the escrow agreement is an
         agreement supplementary to this Agreement, as provided under Section
         365(n) of the Bankruptcy Code.

    12.2 Escrowed Materials shall be released to Siemens upon the occurrence of
         the following events (each, a "Release Condition"):

         12.2.1 A proceeding relating to the liquidation or insolvency of IMPAC
                is commenced and is not dismissed within *** of commencement;

         12.2.2 During the term of the Agreement, IMPAC materially fails to
                provide support in accordance with subsection 9.1.2 within ***
                of receipt by IMPAC of Siemens' written notice of such a failure
                (which notice shall specify in detail the manner in which IMPAC
                is failing to provide this support);

         12.2.3 During the term of the Agreement, IMPAC materially fails to
                provide support in accordance with subsection 9.1.3; or

         12.2.4 During the Maintenance Period, IMPAC materially fails to perform
                the obligations set forth *** in which IMPAC is failing to
                perform).

    12.3 Upon the release of the Escrowed Materials pursuant to a Release
         Condition set forth in subsection 12.2 above, Siemens shall have a
         non-exclusive, non-transferable right, subject to the restrictions set
         forth in this Agreement to use, modify, and make working copies of the
         Escrowed Materials for the sole purpose of supporting and

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         maintaining *** the Products (the "Escrow Support License"); provided,
         however, that the Escrow Support License for each Product shall
         automatically terminate at the end of the applicable Maintenance Period
         for each such Product. Upon the release of the Escrowed Materials
         pursuant to subsection 12.2.1, Siemens shall have a non-exclusive,
         non-transferable right, subject to the restrictions set forth in this
         Agreement to use, reproduce, sublicense, and distribute the Products to
         End-Users in object code form only (the "Escrow Distribution License");
         provided, however, that (1) all such End-User sublicenses shall be
         subject to terms not less restrictive than those set forth in Exhibit B
         of this Agreement; (2) Siemens shall pay a royalty to IMPAC on each
         unit of Product reproduced and distributed to End-Users, which royalty
         shall be equivalent to IMPAC's then-current transfer price for each
         such Product as set forth in the then-current Exhibit A; and (3) the
         Escrow Distribution License shall terminate automatically upon the
         termination or expiration of the then-current term of the Agreement. In
         the event that the source code is released to Siemens pursuant to
         subsections 12.2.2, 12.2.3, or 12.2.4, and ***, Siemens shall have an
         Escrow Distribution License, subject to the terms set forth above.
         Except for sublicensing the right to use the Products to End-Users,
         Siemens shall have no right to sublicense any of the rights granted
         pursuant to this Section 12. Upon the cessation or cure of either of
         the Release Conditions specified in subsection 12.2 above, both the
         Escrow Support License and Escrow Distribution License (if any) shall
         terminate, and Siemens promptly return all copies of the Escrowed
         Materials, or any portion thereof, to ***.

13.Marks.

    13.1 Siemens Marks. Siemens shall own and have sole control of the use of
         all Siemens Marks. IMPAC acknowledges all right, title and interest of
         Siemens in and to the Siemens Marks. IMPAC has no license to or right
         in the Siemens Marks and shall not use them in its marketing or sales
         literature or in any other way, without the prior written consent of
         Siemens. Notwithstanding the foregoing, IMPAC may apply the Siemens
         Marks to Products if requested to do so under any Purchase Order
         accepted by IMPAC, which request shall constitute the prior written
         consent of Siemens. IMPAC may not represent in its marketing and sales
         literature and oral presentations that the Products are compatible with
         Siemens's equipment and that Siemens is a distributor of Products
         without the prior written consent of Siemens, which consent shall not
         be unreasonably withheld.

    13.2 IMPAC Marks. IMPAC shall own and have sole control of the use of all
         IMPAC Marks. Siemens acknowledges all right, title and interest of
         IMPAC in and to the IMPAC Marks. Siemens has no license to or right in
         the IMPAC Marks and shall not use them in its marketing or sales
         literature or in any other way, without the prior written consent of
         IMPAC, which consent shall not be unreasonably withheld.

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14. Confidentiality.

    14.1 Treatment of Confidential Information. Each Recipient receiving
         Confidential Information from a Discloser pursuant to this Agreement
         shall (and shall cause its Affiliates to): (a) hold confidential and
         not disclose to persons or entities other than Recipient's Affiliates
         having a reasonable need to know the Confidential Information in
         connection with the permitted purposes hereunder, without the prior
         written consent of the Discloser, all Confidential Information provided
         by the Discloser or the Discloser's Affiliates; (b) use the
         Confidential Information only for the purposes for which it is
         delivered to the Recipient, and for no other purposes whatsoever,
         except with the prior written consent of the Discloser; and (c) return
         the Confidential Information (with all copies thereof and all portions
         of documents prepared by or for the Receiving Party or Recipient's
         Affiliates which contain Confidential Information) to the Discloser
         (or, at the option of the Recipient, destroy all Confidential
         Information, including all copies thereof and all portions of the
         documents containing Confidential Information, and provide the
         Discloser with a certificate of an officer of the Recipient stating
         that the destruction has occurred) within *** of receipt by the
         Recipient of a written request therefor from the Discloser except to
         the extent the Recipient shall have a continuing right to retain the
         Confidential Information pursuant to this Agreement or other written
         agreement entered into between parties.

    14.2 Exceptions. The obligations imposed by subsection 14.1 hereof shall not
         apply, or shall cease to apply, to any Confidential Information if or
         when, and to the extent that, the Confidential Information: (a) was
         known to the Recipient or the Recipient's Affiliates prior to the
         receipt of the Confidential Information from the Discloser or
         Discloser's Affiliates; (b) was, or becomes through no breach of the
         Recipient's (or any of its Affiliates') obligations hereunder, known to
         the public; (c) becomes known to the Recipient or Recipient's
         Affiliates from sources other than the Discloser or Discloser's
         Affiliates under circumstances not involving any breach of any
         confidentiality obligation between the source and the Discloser or
         Discloser's Affiliates; (d) is independently developed by the Recipient
         or the Recipient's Affiliates, without any use of or reference to the
         Discloser's Confidential Information; or (e) is required to be
         disclosed by law or applicable legal process, provided that the
         Recipient or the Recipient's Affiliates making the disclosure shall (i)
         give the Discloser as much prior notice thereof as is reasonably
         practicable so that the Discloser may seek such protective orders or
         other confidentiality protection as it, in its sole discretion and at
         its sole expense, may elect, and (ii) reasonably cooperate(s) with the
         Discloser in protecting the confidential or proprietary nature of the
         Confidential Information that must be so disclosed (with this duty of
         cooperation not requiring the Recipient or Recipient's Affiliates to
         initiate or participate in any litigation or incur more than de minimis
         out-of-pocket costs).

    14.3 Equitable Relief. Each Recipient acknowledges and agrees that due to
         the unique nature of the Discloser's Confidential Information, there
         can be no adequate remedy at law for any breach of the Recipient's
         confidentiality and use-restriction obligations under this Agreement,
         that any such breach may result in irreparable harm to the

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         Discloser, and that therefore, upon any such breach or threat thereof,
         the Discloser shall be entitled to appropriate equitable relief,
         including injunctive relief, in addition to any remedies it may have
         available at law. Each party hereby waives any right it may have to
         assert that the other party has one or more adequate remedies available
         at law with respect to any breach of this Agreement in connection with
         Confidential Information.

15. Warranties and Disclaimers.

    15.1 Limited Product Warranties. IMPAC warrants to Siemens (and not to any
         third party) that each release of the Products, as delivered to Siemens
         by IMPAC, shall operate substantially in conformance with the
         Documentation for a period of *** from the date of first delivery to
         Siemens of the release. IMPAC further warrants that all Products
         provided by IMPAC to Siemens hereunder shall be free from defects in
         material and workmanship for a period of *** from the date of delivery
         to Siemens. Siemens' sole remedy for breach of the foregoing warranty
         with respect to material and workmanship shall be to return defective
         Products for replacement by IMPAC, or if IMPAC determines that repair
         and replacement is not commercially feasible, IMPAC shall refund the
         amounts paid by Siemens for the same in accordance with the provisions
         of subsection 4.2 of this Agreement.

    15.2 Product Rights. IMPAC warrants that it is the author of the Products
         and owner of all right, title and interest in and to the Products,
         except with respect to those products licensed from Siemens or third
         parties. IMPAC further warrants that it has and shall have at all times
         all rights with respect to the Products necessary to grant the
         licenses, proprietary interests and other rights granted hereunder and
         to meet all obligations hereunder. During the term of this Agreement,
         Siemens shall have uninterrupted and peaceful enjoyment of its rights
         hereunder so long as Siemens performs its obligations hereunder. To the
         extent IMPAC has obtained licenses of any third party software, IMPAC
         agrees to promptly advise Siemens of any conditions, events, or changes
         that may affect or pertain to the continuation of this enjoyment of its
         rights under this Agreement. Notwithstanding the foregoing, the only
         remedies available to Siemens, and the sole liability of IMPAC, for any
         breach of this Section 15.2 relating to the violation or infringement
         of any Intellectual Property Right shall be as provided in Section 17
         below.

    15.3 Infringement. IMPAC warrants, any information provided to Siemens
         regarding existing or past claims or disputes not withstanding, that no
         part of the Product infringes or will infringe any patent, copyright,
         trade secret, trademark or other proprietary right of any third party;
         provided, however, that the only remedies of Siemens for breach of the
         foregoing warranty shall be as provided in Section 17. Except as
         disclosed in writing to Siemens at or prior to execution of this
         Agreement, IMPAC represents that, to the best of its knowledge, no
         claim or action relating to the infringement of any patent, copyright,
         trade secret, trademark or other proprietary right has been made
         against IMPAC, or against any entity from which IMPAC has obtained
         rights, with respect to any part of the Products.

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    15.4 IMPAC Services. IMPAC warrants that (i) the personnel of IMPAC
         originally assigned to perform any specific services will be so
         assigned throughout the performance of such services, so long as such
         personnel remain employed by IMPAC and to the extent reasonably
         necessary for the timely completion thereof and (ii) all services of
         IMPAC relating to the Products shall be performed in a timely
         (commensurate with the nature and degree of the reasonable needs of
         Siemens and its customers) and professional manner by qualified
         personnel of IMPAC familiar with the Products and shall conform in all
         material respects to quality standards generally observed in the
         industry for similar services.

    15.5 Compliance. Each party warrants that (i) it shall furnish all services
         and materials hereunder in compliance with applicable law and in the
         course of rendering the same, shall not violate or in any way infringe
         upon the rights of the other party or third parties, including
         property, contractual, employment, trade secret, proprietary
         information and nondisclosure rights, or any trademark, copyright or
         patent rights and (ii) all employees, servants and agents of each
         party, whenever on the other party's premises, shall obey all
         reasonable instructions issued by the other party, including work
         schedule and security procedures. Notwithstanding the foregoing, the
         only remedies available to Siemens, and the sole liability of IMPAC,
         for any breach of this Section 15.5 relating to the violation or
         infringement of any Intellectual Property Right shall be as provided in
         Section 17 below.

    15.6 Disclaimer. EXCEPT AS EXPRESSLY SET FORTH IN SECTION 15 ABOVE AND TO
         THE EXTENT PERMITTED BY APPLICABLE LAW, IMPAC DISCLAIMS ALL WARRANTIES,
         EXPRESS, IMPLIED AND STATUTORY, WITH RESPECT TO ANY PRODUCTS,
         INFORMATION, MATERIALS OR SERVICES PROVIDED BY IMPAC HEREUNDER,
         INCLUDING WITHOUT LIMITATION WARRANTIES OF MERCHANTABILITY, FITNESS FOR
         A PARTICULAR PURPOSE, ACCURACY, COMPLETENESS, ERROR-FREE SERVICE,
         UNINTERRUPTED SERVICE, NON-INFRINGEMENT, TITLE AND NON-INTERFERENCE.

16. Quality Assurance and Control.

    16.1 Inspection and Testing. Products supplied to Siemens under this
         Agreement shall be inspected by IMPAC (using representative sampling
         where appropriate) and, with respect to each new release, tested in
         accordance with the U.S. FDA and the MDD Quality System Requirements.
         IMPAC shall keep a record of the test results for a period of *** after
         delivery of each Product and provide Siemens with copies of these
         records on request. IMPAC shall supply to Siemens only Products that
         conform in all material respects to the Documentation and that have
         passed all IMPAC inspections. IMPAC shall supply *** with each Product
         supplied. IMPAC shall give Siemens' Project Manager written notice, not
         less than *** in advance of anticipated testing dates and telephone
         notice no less than *** in advance of actual testing, for Enhancements
         of the Products, and Siemens shall have the option of being present at
         its own expense for such testing.

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    16.2 Medical Device Compliance. The VMI Software, SEQUENCER, ViewStation,
         MLC Fit subsystems of the Products shall be marketed and distributed by
         IMPAC as medical devices as defined in the United States Food, Drug,
         and Cosmetic Act and the regulations thereunder (and similar laws in
         other countries) to the extent permitted by applicable law. IMPAC shall
         comply with all statutes and regulations applicable to design,
         manufacture, and distribution of the Products as medical devices,
         including those relating to the Quality System Regulations,
         establishment registration, device listing, pre-market approval or
         notification and medical device reporting. Siemens may, upon request,
         inspect and audit at IMPAC's facility the quality control procedures
         and methods employed by IMPAC in development and manufacture of the
         Products. IMPAC agrees also to obtain *** any additional approval or
         clearances necessary for the Product to be distributed ***. The parties
         shall mutually cooperate with respect to any reporting or approvals
         required by law or this subsection 16.2 in connection with the
         Products.

17. Indemnities; Intellectual Property Infringement.

    17.1 Personal Injury, Property Damage. Subject to subsection 17.3 below,
         IMPAC agrees to defend, indemnify and hold Siemens and its directors,
         employees, agents and Affiliates harmless from and against any and all
         damages, liability, costs and expenses (including without limitation
         reasonable attorneys' fees) arising under any third party action to the
         extent arising out of personal injury or death of a person or damage to
         tangible property (specifically excluding data and other intellectual
         property) caused or alleged to have been caused by defects in the
         Products or their manufacture or design (except to the extent that the
         defects are caused by modifications to the Products not performed or
         authorized by IMPAC). Subject to subsection 17.3 below, Siemens agrees
         to defend, indemnify and hold IMPAC and its directors, employees,
         agents and Affiliates harmless from and against any and all damages,
         liability costs and expenses (including without limitation reasonable
         attorneys' fees) in connection with any third party action to the
         extent arising out of personal injury or death of a person or damage to
         tangible property (specifically excluding data and other intellectual
         property) caused or alleged to have been caused by defects in the
         equipment and/or other products with which Siemens sublicenses or
         otherwise distributes the Products.

    17.2 Infringement Indemnity. Subject to subsection 17.3 below, IMPAC agrees
         to defend, indemnify and hold Siemens and its directors, employees,
         agents and Affiliates harmless from and against any and all damages,
         liability, costs and expenses (including without limitation reasonable
         attorneys' fees) arising under any third party action to the extent
         that the action alleges or proves that any Product, as provided by
         IMPAC to Siemens hereunder, infringes any United States patent,
         copyright, trademark or trade secret, except to the extent that any
         infringement arises from: (a) any modification to any Product after
         being provided to Siemens by IMPAC, or (b) the combination of any
         Product with any other product or equipment distributed by Siemens or
         its sublicensees. Subject to subsection 17.3 below, Siemens agrees to
         defend, indemnify and hold IMPAC and its directors, employees, agents
         and

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         Affiliates harmless from and against any and all damages, liability,
         costs and expenses (including without limitation reasonable attorneys'
         fees) arising under any third party action to the extent that the
         action alleges or proves that any Product infringes any United States
         patent, copyright, trademark or trade secret due to: (a) any
         modification to the Product after being provided to Siemens by IMPAC,
         or (b) the combination of the Product with any other product or
         equipment distributed by Siemens or its sublicensees.

    17.3 Conditions of Indemnification. In connection with any claims for which
         indemnification may be sought under this Section 17, the indemnified
         party shall give the indemnifying party prompt written notice of the
         claim, reasonable information and assistance (at the indemnifying
         party's request and expense) in connection with the defense and/or
         settlement of the claim and, subject to the provisions of this section,
         the sole right to control and direct the investigation, preparation,
         defense and settlement of the claim. In the event that the indemnified
         party fails to provide this notice or reasonable information or
         assistance, the indemnifying party shall not be relieved of its
         obligations under this Section 17 except to the extent that it is
         prejudiced by the failure. The indemnified party shall have the right
         to participate in the defense and/or settlement of the claim with
         counsel of its choosing at the indemnified party's expense. The
         indemnifying party shall not enter into any settlement adversely
         affecting any of the indemnified party's rights or obligations without
         the indemnified party's prior written consent, which shall not be
         unreasonably withheld.

    17.4 Infringement Options. If all or any part of a Product is, or in the
         reasonable opinion of IMPAC may become, the subject of any claim, suit
         or proceeding for infringement of any United States or foreign patent,
         trademark, copyright or trade secret, then without limiting any other
         remedy to which Siemens may be entitled under this Section 17, IMPAC
         may, and in the event of any adjudication that a Product or any part
         thereof infringes any United States or foreign patent, trademark,
         copyright or trade secret or if the licensing or use of a Product or
         any part thereof is enjoined, IMPAC shall, at its expense, do one of
         the following things: (a) procure for Siemens the right under the
         affected patent, trademark, copyright or trade secret to use or
         sublicense, as appropriate, the Product or the affected part thereof;
         (b) replace the Product or affected part thereof with other
         non-infringing software which satisfies the Documentation and other
         requirements of this Agreement; (c) suitably modify the Product or
         affected part thereof, without material loss of performance or
         functionality, to make it non-infringing; or (d) if Siemens determines
         that none of the foregoing remedies is commercially practicable, refund
         the payments paid by Siemens for the Product, ***.

    17.5 Exclusive Remedies. SECTIONS 17.2, 17.3 AND 17.4 STATE THE ENTIRE
         LIABILITY AND OBLIGATION OF THE PARTIES AND THEIR AFFILIATES AND THE
         EXCLUSIVE REMEDIES OF THE PARTIES AND THEIR AFFILIATES WITH RESPECT TO
         ANY ALLEGED INFRINGEMENT OF PATENT, TRADEMARK, COPYRIGHT, TRADE SECRET
         OR OTHER


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         INTELLECTUAL PROPERTY RIGHT BY THE PRODUCTS OR ANY PART THEREOF.

18. Limitations of Liability. EXCEPT WITH RESPECT TO THE INDEMNIFICATION
    OBLIGATIONS UNDER THIS AGREEMENT AND TO THE MAXIMUM EXTENT PERMITTED BY
    APPLICABLE LAW: (A) NEITHER PARTY SHALL BE LIABLE TO THE OTHER OR ITS
    AFFILIATES UNDER THIS AGREEMENT OR IN CONNECTION WITH ITS SUBJECT MATTER FOR
    SPECIAL, INDIRECT, PUNITIVE OR CONSEQUENTIAL DAMAGES (INCLUDING BUT NOT
    LIMITED TO LOSS OF BUSINESS GOODWILL, REVENUE OR PROFITS); AND (B) EXCEPT
    FOR SIEMENS' FEE PAYMENT OBLIGATIONS HEREUNDER, NEITHER PARTY SHALL BE
    LIABLE TO THE OTHER OR ITS AFFILIATES UNDER THIS AGREEMENT OR IN CONNECTION
    WITH ITS SUBJECT MATTER FOR ANY AMOUNTS IN EXCESS OF THE AGGREGATE AMOUNTS
    RECEIVED BY IMPAC UNDER THIS AGREEMENT. THIS SECTION CONSTITUTES AN
    ESSENTIAL TERM OF THIS AGREEMENT AND SHALL BE EFFECTIVE EVEN IN THE EVENT OF
    THE FAILURE OF ANY REMEDY HEREUNDER, EXCLUSIVE OR OTHERWISE.

19. Term and Termination.

    19.1 Term. The term of this Agreement shall be for a period of five (5)
         years commencing upon the Effective Date, unless earlier terminated in
         accordance herewith.

    19.2 Termination. In addition to any other remedies it may have, either
         party may terminate this Agreement at any time, without any liability
         arising from the termination, by providing written notice of
         termination to the other party following the occurrence of one or more
         of the following circumstances:

         19.2.1 the commencement of any proceeding by the other party for relief
                under the United States Bankruptcy Code (or similar law of any
                foreign jurisdiction), any assignment by the other party for the
                benefit of any of its creditors, or the appointment of a
                receiver for all or a substantial part of the other party's
                business or assets; or

         19.2.2 the other party's failure to pay money due in accordance with
                this Agreement, this failure remaining uncured *** after the
                other party's receipt of written notice thereof; or

         19.2.3 the breach of any agreement, obligation, covenant or
                representation of the other party under this Agreement, this
                breach remaining uncured in any material respect *** thereof
                from the first party.

    19.3 Effects of Termination. Upon expiration or termination of this
         Agreement for any reason, except as expressly provided in this
         Agreement, the license rights granted hereunder shall immediately
         terminate. Each party shall return to the other all copies


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         of any and all Confidential Information of the other party in its
         possession or shall certify to the other party that all of this
         Confidential Information has been destroyed, except that Siemens shall
         not be required to return or certify the destruction of any
         Confidential Information of IMPAC that is necessary for ongoing support
         by Siemens of the Products distributed by Siemens in accordance with
         this Agreement. Except in the event of termination of this Agreement by
         IMPAC pursuant to subsection 19.2 above, for a period of *** following
         the expiration or termination of this Agreement, IMPAC shall supply
         Products to Siemens (and Siemens shall have the right to sub-license
         End-Users as provided in subsection 6.1) to the extent necessary to
         fulfill any purchase order accepted by Siemens prior to expiration or
         termination of the Agreement, in accordance with the following
         conditions:

         19.3.1 In the first *** following the effective date of termination or
                expiration of the Agreement (the "Termination Date"), Products
                covered by accepted Purchase Orders in effect as of the
                Termination Date shall be supplied to Siemens at prices in
                effect as of the Termination Date; provided, however, that
                Siemens shall provide a written list to IMPAC of all these
                Purchase Orders no later than *** after the Termination Date,
                which list shall contain the customer name, quantities for each
                Product ordered, and estimated dates of delivery; and

         19.3.2 During the period beginning *** after the Termination Date and
                ending *** following the Termination Date, Products covered by
                accepted Purchase Orders in effect as of the Termination Date
                shall be supplied to Siemens at prices which shall not exceed
                *** in effect as of the Termination Date; provided, however,
                that Siemens shall provide a written list to IMPAC of all these
                Purchase Orders no later than *** after the Termination Date,
                which list shall contain the customer name, quantities for each
                Product ordered, and estimated dates of delivery.

    19.4 Additional Product Copies. During the post-termination period set forth
         in subsection 19.3 above, Siemens shall be entitled to make *** of any
         new releases of the Products provided by IMPAC for Siemens's internal
         archival, back-up, training and support purposes, which copies are to
         be retained at all times only at Siemens's facilities. Siemens shall
         erase or destroy all copies of previous releases superseded thereby
         other than not more than one (1) copy to be used only for archival
         purposes.

    19.5 Survival. The following provisions shall survive the termination or
         expiration of this Agreement: Sections ***.



20. Governing Law, Jurisdiction and Venue. This Agreement shall be governed by
    and construed under applicable U.S. federal law and the laws of the State of
    California, without regard to conflicts of laws principles and without
    regard to the United Nations Convention on Contracts for the International
    Sale of Goods. The parties agree that the California state and U.S. federal
    courts situated in Contra Costa County in the State of California shall have
    exclusive jurisdiction to resolve any disputes with respect to this
    Agreement, with each party

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    irrevocably consenting to the jurisdiction thereof for any actions, suits or
    proceedings arising out of or relating to this Agreement. Each party waives
    any right that it may have to assert that any of the foregoing forums is not
    convenient.

21. General.

    21.1 Independent Contractors. In performing their respective obligations
         hereunder, each party shall act at all times as an independent
         contractor. Nothing in this Agreement shall be construed or applied to
         create a relationship of principal and agent or employer and employee
         between the parties, and neither of them shall make any commitment,
         take any action or incur any expense in the name of or purporting to
         bind the other party or its Affiliates.

    21.2 Further Assurances. The parties shall, and shall cause their respective
         employees, agents and representatives to, prepare and execute and
         deliver, at the request and expense of any party hereto, any and all
         documents or instruments reasonably necessary or appropriate to create,
         evidence, or confirm the grant, discharge or release, as the case may
         be, of any right, interest or obligation required by the provisions of
         this Agreement.

    21.3 Entire Agreement and Amendment. This Agreement represents the entire
         understanding and agreement of the parties with respect to the
         particular subject matter hereof and supersedes all prior
         communications, agreements and understandings between the parties
         relating to the subject matter hereof, including without limitation
         that certain Software Development and OEM License Agreement between the
         parties, dated as of October 1, 1992, as subsequently amended. In the
         event of a conflict between this Agreement and any exhibit or purchase
         order, this Agreement shall govern. This Agreement may not be modified
         or amended except by a written instrument duly executed by both
         parties.

    21.4 Costs and Attorneys' Fees. The prevailing party in any action to
         enforce this Agreement shall be entitled to recover reasonable costs
         and expenses in connection with the enforcement, including without
         limitation reasonable attorneys' fees and expenses.

    21.5 Cumulative Remedies. Except as otherwise expressly set forth herein,
         all remedies available to either party for breach of this Agreement are
         cumulative and may be exercised concurrently or separately, and the
         exercise of any one remedy shall not be deemed an election of that
         remedy to the exclusion of any other remedy.

    21.6 Waivers. No right under this Agreement or breach hereof may be waived
         except in writing signed by the parties hereto. The failure of either
         party to require performance of any provision of this Agreement shall
         not be construed as a waiver of that party's rights to insist on
         performance of the provision or any other provision at some other time.


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    21.7  Assignment and Binding Effect. This Agreement may not be assigned by
          either Party without the prior written consent of the other; provided,
          however, that either party may assign this Agreement in its entirety
          to an Affiliate or successor in interest to the business of the party,
          after written notice to the other party, if the Affiliate or successor
          is able to and does fulfill the obligations of the assigning party.
          This Agreement shall be binding on, and inure to the benefit of, the
          respective successors of the parties thereto.

    21.8  Counterparts. This Agreement may be signed in duplicate originals,
          each of which shall constitute an original document.

    21.9  Notices. Any notice in connection with this Agreement shall be in
          writing and delivered by hand or after being mailed, postage prepaid,
          certified or registered mail, return receipt requested, addressed as
          set forth on the signature page below, to the attention of "Legal
          Department," or any other address as a party designates by giving
          notice to the other party in accordance with this section. Notices
          shall be effective only upon receipt.

    21.10 Force Majeure. Neither party shall be responsible for any failure to
          perform or delay in performing any of its obligations hereunder where
          and to the extent that the failure or delay results from causes
          outside the reasonable control of the party.

    21.11 Foreign Reshipment Liability. Notwithstanding anything contained in
          this Agreement, Siemens shall not export or re-export any Product or
          information pertaining thereto in violation of any United States law
          applicable to the export or re-export of the Product or information.

    21.12 Exhibits. The following Exhibits are attached hereto and made a part
          of this Agreement:


              Exhibit A: Products and Training with Pricing

              Exhibit B: Form of End-User Agreement

              Exhibit C: Affidavit of Destruction or Re-Registration and
                         Indemnity Agreement


              Exhibit D: Form of Confidentiality Agreement

                                       21

<PAGE>

                                  CONFIDENTIAL

         The parties have caused their duly authorized representatives to
execute and deliver this Agreement as of the Effective Date.
<TABLE>
<CAPTION>


<S>                                                          <C>
IMPAC Medical Systems, Inc.                                  Siemens Medical Systems, Inc.

By: /s/ Joseph K. Jachinowski                                By: /s/ Patrick W. Boyle
    ----------------------------------                           --------------------

Name: Joseph K. Jachinowski                                  Name: Patrick W. Boyle
     -----------------------------------                          -----------------

Title: CEO                                                   Title: President, OCS
       -----------------------------                                ------------------------------


Address:                                                     Address:
100 West Evelyn Avenue                                       4040 Nelson Avenue
Mountain View, California 94041                              Concord, California 94520

Tel 650-623-8800                                             Tel 925-602-8040
    --------------------------------                            ----------------------------------

Fax 650-623-8911                                             Fax 925-602-8041
    --------------------------------                            ----------------------------------
</TABLE>

<TABLE>
<CAPTION>

<S>                                                          <C>
4-25-01

                                                             /s/ Bernd Haetzel
                                                             VP Finance & Administration

                                                             4-25-01
</TABLE>
                                       22


<PAGE>
                    Exhibit A, Product and Training, with Pricing
                                       ***

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***Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

IMPAC Medical Systems, Inc. Confidential

<PAGE>
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***Certain information on this page has been omitted and filed separately
with the Commission. Confidential treatment has been requested with respect
to the omitted portions.

IMPAC Medical Systems, Inc. Confidential

<PAGE>
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 Notes:
   1 ***



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   3 ***

***Certain information on this page has been omitted and filed separately
with the Commission. Confidential treatment has been requested with respect
to the omitted portions.

IMPAC Medical Systems, Inc. Confidential




<PAGE>

                 Exhibit A, Product and Training, with Pricing
                                       ***

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***Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

IMPAC Medical Systems, Inc. Confidential

<PAGE>
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***Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

IMPAC Medical Systems, Inc. Confidential

<PAGE>
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 Notes:

    1 ***



    2 ***

    3 ***


***Certain information on this page has been omitted and filed separately with
the Commission. Confidential treatment has been requested with respect to the
omitted portions.

IMPAC Medical Systems, Inc. Confidential













<PAGE>

                                    EXHIBIT B

                          MINIMUM END-USER RESTRICTIONS

         Each End-User Agreement shall contain provisions at least as protective
of IMPAC as those set forth in this Exhibit B.

1.   Restrictions. End-User may not: (i) reproduce or copy any of the Products
     other than to make a reasonable number of copies for back-up and/or
     archival purposes; (ii) modify or create any derivative works of any of the
     Products; (iii) decompile, disassemble, reverse engineer, or otherwise
     attempt to derive the source code for any of the Products; (iv) disclose,
     redistribute, encumber, sell, rent, lease, sublicense, or otherwise
     transfer rights to any of the Products, except that End-User may transfer
     all of End-User's rights in such Products to a third party who agrees in
     writing to be bound by all of the provisions of this Agreement; or (v)
     remove or alter any trademark, logo, copyright or other proprietary
     notices, legends, symbols or labels in any of the Products.

2.   Ownership. Except for the licenses expressly set forth in this Agreement,
     all right, title and interest in and to the Products shall remain with
     Distributor and its licensor(s). End-User acknowledges such ownership and
     intellectual property rights and will not take any action to jeopardize,
     limit or interfere in any manner with Distributor's or its licensors'
     ownership of or rights with respect to the Products.

3.   Disclaimers. EXCEPT AS EXPRESSLY PROVIDED IN THIS AGREEMENT, THE PRODUCTS
     (INCLUDING WITHOUT LIMITATION THE RELATED DOCUMENTATION) ARE PROVIDED ON AN
     "AS IS" BASIS, WITHOUT WARRANTY OF ANY KIND, INCLUDING WITHOUT LIMITATION
     THE WARRANTIES THAT THEY ARE FREE OF DEFECTS, ERROR-FREE, MERCHANTABLE, FIT
     FOR A PARTICULAR PURPOSE OR NON-INFRINGING.

4.   Limitation of Liability. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW,
     IN NO EVENT WILL DISTRIBUTOR OR ITS LICENSORS BE LIABLE FOR ANY INDIRECT,
     SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF OR
     INABILITY TO USE THE PRODUCTS, INCLUDING, WITHOUT LIMITATION, DAMAGES FOR
     LOSS OF GOODWILL, WORK STOPPAGE, EQUIPMENT FAILURE OR MALFUNCTION, OR COST
     OF SUBSTITUTE GOODS OR SERVICES, EVEN IF ADVISED OF THE POSSIBILITY
     THEREOF, AND REGARDLESS OF THE LEGAL OR EQUITABLE THEORY (CONTRACT, TORT OR
     OTHERWISE) UPON WHICH THE CLAIM IS BASED.

<PAGE>


                            [SIEMENS LOGO GOES HERE]
                                    EXHIBIT C
             AFFIDAVIT OF DESTRUCTION OR RE-REGISTRATION OF COMPUTER
                        SOFTWARE AND INDEMNITY AGREEMENT

THIS IS TO CERTIFY that the undersigned says that he is an authorized officer of
Siemens Medical Systems Oncology Care Systems, a DELAWARE corporation
("SMS-OCS"), and that SMS-OCS has discontinued the use of software ordered from
IMPAC Medical Systems, Inc., a CALIFORNIA corporation, ("IMPAC") which was
installed upon a CPU system for the purpose designated below.

The undersigned hereby represents that the statements made herein are made as an
inducement to IMPAC to accept this affidavit, to take the action designated
below, and to update its records accordingly as an acknowledgement of the
discontinuation of use of said software. The undersigned agrees as follows:

   1. To indemnify IMPAC against any losses or damages that IMPAC may in
      any way sustain, incur or become liable for as a consequence of the
      acceptance of this Affidavit and Indemnity Agreement.

   2. To take any other steps and to perform any and all further acts
      necessary to ensure that only one Copy of licensed software is in
      use. SMS-OCS hereby states that it has caused the previously
      registered IMPAC software to be erased and destroyed from said CPU
      system and disabled the program so that it may not be used by the
      owner of the said CPU system or by anyone else.
<TABLE>
<CAPTION>
                  PURPOSE                                            ACTION
                  -------                                            ------
      <S>                                     <C>
      a) [] NetWare license change             -  re-register existing software at no additional charge.
      b) [] DOS license change                 -  re-register existing software at no additional charge.
      c) [] Stand alone to network upgrade     -  re-register existing software at no additional charge.
</TABLE>
                                                                 OR

   3. To take any other steps and to perform any and all further acts
      necessary to prevent any further use of said software. SMS-OCS
      hereby states that it has caused the IMPAC software to be erased and
      destroyed from said CPU systems and disabled the program so that it
      may not be used by the owner of the CPU system of by anyone else.

<TABLE>
<CAPTION>
                          PURPOSE                                                     ACTION
                          -------                                                     ------
      <S>                             <C>
      a) [] Demonstration/testing     -  reduce total count of demonstration/testing licenses in use.
      b) [] Incorrect software order  -  issue credit or refund if payment for said software has been received
</TABLE>
      Signed this  day of

      SIEMENS MEDICAL SYSTEMS ONCOLOGY CARE SYSTEMS, Inc.

      Signature:  _____________________________________________________________

      Name/Title: _____________________________________________________________

      Site/User: ____________________________   Old Registration Key:__________

                                                New Registration Key:__________

      Previous Software Installed:    New Software Installed (if applicable):

      _________________________________________________________________________

      _________________________________________________________________________

      _________________________________________________________________________

<PAGE>
                                    Exhibit D

                        FORM OF CONFIDENTIALITY AGREEMENT

         THIS CONFIDENTIALITY AGREEMENT (the "Agreement") is entered into this
______ day of __________, 20__, by and between Siemens Medical Systems, Inc.,
the "Disclosing Party") and _________________________________________, (the
"Receiving Party") for the purpose of preventing the unauthorized disclosure of
Confidential Information (as defined below) of the Disclosing Party which may be
disclosed to the Receiving Party as an auditor retained in connection with an
audit of the Disclosing Party's books, records and employees pursuant to that
certain Software Distribution Agreement between Siemens Medical Systems, Inc.,
and IMPAC Medical Systems, Inc. ("the Distribution Agreement").

         For purposes of this Agreement, Confidential Information shall mean all
confidential or proprietary (written, recorded or oral) information or data (i)
marked or identified by the Disclosing Party as being confidential or
proprietary or (ii) which the Receiving Party should reasonably understand to be
confidential or proprietary. By way of example, Confidential Information
includes research, developmental, engineering, manufacturing, technical,
marketing, sales, financial, operating, performance, cost, business and process
information or data, know-how, and computer programming and other software and
software techniques.

         In consideration of the Disclosing Party's disclosure of Confidential
Information of the Receiving Party, the Receiving party hereby agrees as
follows:

         1. The Receiving Party shall hold and maintain the Confidential
Information in strict confidence and in trust for the sole and exclusive benefit
of the Disclosing Party.

         2. The Receiving party shall not, without the prior written approval of
the Disclosing Party, use for its own benefit, publish or otherwise disclose to
others, or permit the use by others for their benefit for to the detriment of
the Disclosing Party, any of the Confidential Information except only to the
extent that it is necessary for the Receiving Party to disclose any part of the
Confidential Information to a party to the Distribution Agreement in connection
with performing the Receiving Party's functions as an auditor pursuant to the
terms of the Distribution Agreement.

         3. The Receiving Party shall carefully restrict access to the
Confidential Information to those of its officers, directors, employees and
professional advisors who clearly need such access in order to participate on
behalf of the Receiving Party in the audit of the Disclosing Party's books,
records and employees as provided for in the Distribution Agreement. The
Receiving Party further warrants and represents that it will advise each of the
persons to whom it provides access to any of the Confidential Information
pursuant to the foregoing sentence that such persons are strictly prohibited
from making any use, publishing or otherwise disclosing to others or permitting
others to use for their benefit or to the detriment of the Disclosing Party, any
of the Confidential Information.

         4. This Agreement shall continue in full force and effect for a period
of two (2 ) years from the date hereof and the obligations of confidentiality
set forth herein shall survive in perpetuity, except that the Receiving Party's
obligations hereunder shall not extend to any of the


<PAGE>

         Confidential Information which the Receiving Party can demonstrate (i)
was in the public domain on the date of this Agreement, (ii) comes into the
public domain after the date of this Agreement without fault of the Receiving
Party, or (iii) is rightfully received by Receiving Party from a party under no
duty of confidentiality to the Disclosing Party.

         5. The Receiving Party agrees that the Disclosing Party shall have the
right to apply to a court of competent jurisdiction for an order restraining any
disclosure or misappropriation of any of the Confidential Information in
violation of this Agreement and for such other relief as the Disclosing Party
shall deem appropriate, such right of the Disclosing Party to be in addition to
the remedies otherwise available to the Disclosing Party at law or in equity.

         6. The Receiving Party shall return to the Disclosing Party any and all
records, notes and other written, printed or tangible materials pertaining to
the Confidential Information immediately upon the written request of the
Disclosing Party.

         7. This Agreement and the Receiving Party's obligations hereunder shall
be binding upon the representatives, assigns and successors of the Receiving
Party and shall inure to the benefit of the assigns and successors of the
Disclosing Party.

         8.       This Agreement shall be governed by and construed in
accordance with the internal laws of the State of California.

         9. If any action at law or in equity is brought to enforce or interpret
the provisions of this Agreement, the prevailing party in such action shall be
entitled to reasonable attorney's fees.

         10. This Agreement constitutes the sole understanding of the parties
with respect to the subject matter hereof and may not be amended or modified
except in a writing signed by each of the parties.

         IN WITNESS WHEREOF, the parties hereto have entered into this Agreement
on the date set forth above.

Siemens Medical Systems, Inc.                            RECEIVING PARTY:

________________________                    ___________________________


By:______________________                   By:________________________

Its:_____________________                   Its:_______________________

<PAGE>


                                  CONFIDENTIAL

                           IMPAC MEDICAL SYSTEMS, INC.

                               FIRST AMENDMENT TO
                         SOFTWARE DISTRIBUTION AGREEMENT

         This First Amendment (First Amendment) to the Software Distribution
Agreement (Agreement) is entered into by and between IMPAC Medical Systems,
Inc., a California corporation (IMPAC), and Siemens Medical Systems, Inc., a
Delaware corporation (Siemens).

                                   Background

         The parties entered into a Software Distribution Agreement on April 25,
2001 that provided for the distribution of IMPAC Products by Siemens. The
Agreement set out specific transfer prices for the Products that included
certain third-party products.

         The parties desire to amend and modify the Agreement to ***.

         Accordingly, the parties agree as follows:

1. The following sentence is added to the end of Section 3.1 of the Agreement:

         This limitation on price modification frequency and the cap on annual
         price increases shall not apply to ***.


2. Exhibit A to the Agreement is deleted in its entirety and is replaced with
the new Exhibit A attached to this First Amendment.


         In all other respects the Agreement shall remain unmodified and in full
force and effect. In the event of any inconsistency between the terms and
conditions of this First Amendment and the terms and conditions of the
Agreement, the terms and conditions of this First Amendment shall govern and
control.

         This First Amendment may be executed in two or more counterparts, each
of which shall be deemed an original, but all of which together will constitute
one and the same instrument.


         The parties have caused this First Amendment to be signed by their duly
authorized representatives.


*** Certain information on this page has been omitted and filed separately with
    the Commission. Confidential treatment has been requested with respect to
    the omitted portions.

<PAGE>


IMPAC Medical Systems, Inc.                       Siemens Medical Systems, Inc.

By: /s/ Joseph K. Jachinowski                     By: /s/ Ajit Singh
    -----------------------------------               --------------

Name: Joseph K. Jachinowski                       Name: Ajit Singh
      ---------------------------------                 ----------

Title: CEO                                        Title: President, OCS
       --------------------------------                  --------------

Date: 9/23/01                                     Date: 9/13/01
      ---------------------------------                 -------

Address:                                          Address:
100 West Evelyn Avenue                            4040 Nelson Avenue
Mountain View, California 94041                   Concord, California 94520

Tel (650) 623-8800                                Tel (925) 602-8040

Fax (650) 623-8911                                Fax (925) 602-8041






IMPAC--Siemens First Amendment to Software Distribution Agreement 8-1-01    2