<PAGE>

                                                                    Exhibit 10.1

          Confidential Materials omitted and filed separately with the
         Securities and Exchange Commission. Asterisks denote omissions.

[ASPECT MEDICAL SYSTEMS LOGO]                        [BRINGING INSIGHT OUT LOGO]

                     OEM DEVELOPMENT AND PURCHASE AGREEMENT

Agreement dated this 24th day of July 2003, by and between Aspect Medical
Systems, Inc., a Delaware corporation with its principal offices located at 141
Needham Street, Newton, Massachusetts ("Aspect") and Datascope Corp., a Delaware
corporation with its principal offices located at 800 MacArthur Boulevard,
Mahwah, NJ ("Datascope") for the purchase and/or license by Datascope Corp. of
products under the terms and conditions contained in this Agreement.

1    BACKGROUND

         1.1      Aspect is a developer, manufacturer and distributor of medical
                  devices, equipment, related hardware, software and related
                  products and accessories.

         1.2      Datascope is a developer, manufacturer and distributor of
                  medical devices, equipment, related hardware, software and
                  related products and accessories, including patient monitors.

         1.3      Datascope desires to integrate Aspect's BIS technology into
                  Datascope's multiparameter patient monitors.

         1.4      Aspect agrees to sell and/or license to Datascope the products
                  described below, subject to the terms and conditions contained
                  in this Agreement.

2    DEFINITIONS.

         2.1      "Aspect's Bispectral Index" or "BIS" is Aspect's proprietary
                  processed EEG parameter that may be used as an aid in
                  monitoring the effects of certain anesthetic agents.

         2.2      "Datascope Patient Monitor" means any multi-parameter patient
                  monitoring system manufactured by or for Datascope . When the
                  [**] Development Project is complete, the Datascope [**]
                  System will allow the Datascope Patient Monitor to display BIS
                  and provide setup and operation information (user interface),
                  alarming, and network connectivity.

         2.3      [**].

         2.4      "Aspect [**] Kit" is the Aspect components of the Datascope
                  [**] System that are developed and manufactured by or for
                  Aspect and licensed/sold to Datascope under this Agreement
                  including [**]

         2.5      "Monitor Cable" is the cable that connects the [**] to the
                  Datascope patient

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                  monitor. This cable will be jointly designed by Aspect and
                  Datascope and supplied by Datascope or its manufacturer for
                  final assembly with the Aspect [**] Kit.

         2.6      "Datascope [**] System" is the combined Aspect [**] Kit and
                  Monitor Cable.

         2.7      "Aspect BIS Sensor" means a single use disposable sensor
                  manufactured by Aspect for use with the Aspect [**] Kit in the
                  OR and ICU that is required to generate Aspect's Bispectral
                  Index. These sensors include the BIS Quatro Sensor, the BIS
                  Extend Sensor and the BIS Pediatric Sensor.

         2.8      "Aspect BIS Engine" is the processing unit for deriving BIS
                  data from the raw EEG signal and consists of a PC board and
                  connectors. This component is used in OEM modules to provide
                  the BIS index on modular patient monitoring systems.

         2.9      "Aspect Products" means Aspect [**] Kit and any other product
                  that can be ordered by Datascope as listed in Exhibit A
                  (Aspect Products and Purchase Prices).

         2.10     "Software" means Aspect software programs in binary code form
                  that are designed for use with the Aspect [**] Kit.

         2.11     "Documentation" means the [**] Serial Interface Specification.

         2.12     "Party" or "Parties" shall mean Aspect and Datascope each
                  individually or jointly.

3.   [**] DEVELOPMENT PROJECT.

         3.1      Project Management.

                  3.1.1    Each Party shall appoint a "Project Manager" who
                           shall oversee and manage the joint project on a
                           day-to-day basis.

                  3.1.2    The Project Managers shall meet regularly based on
                           the project needs to assess the project status and
                           discuss and resolve any issues or problems. These
                           meetings may be held face-to-face or as telephone or
                           video conferences. In addition to this, Datascope
                           shall have the right, but no more than once per year,
                           to do an audit of Aspect's facility, procedures,
                           manufacturing operations and vendors for regulatory
                           purposes.

                  3.1.3    Each Party shall bear its own communication and
                           travel costs.

                  3.1.4    All communication in conjunction with this Agreement
                           shall be directed to the appropriate person and
                           address as listed in Exhibit C (Contact
                           Persons/Addresses).

         3.2      Datascope Responsibilities.

                  (a)      Datascope, or one of its designees, will design,
                           develop, test and manufacture the Monitor Cable.

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                  (b)      Datascope shall integrate and test the integration of
                           the components of the Aspect [**] Kit with the
                           Datascope Patient Monitors.

         3.3      Aspect Responsibilities.

                  (a)      Aspect will jointly design (with Datascope) the
                           Monitor Cable.

                  (b)      Aspect shall design, develop, and test the Aspect
                           [**] Kit according to the mutually agreed
                           specifications.

                  (c)      Aspect will certify the implementation of BIS
                           software into the host monitoring system and the
                           integration of the Datascope [**] System into the
                           associated monitoring systems.

4.   PURCHASE AND SALE OBLIGATIONS:

         4.1      Licenses - General.

                  Subject to the terms and conditions of this Agreement, Aspect
                  agrees to sell to Datascope the Aspect Products listed on
                  Exhibit A (Aspect Products and Purchase Prices). The
                  components of the Aspect [**] Kits purchased from Aspect under
                  this Agreement shall only be used as components in,
                  incorporated into or integrated with the [**] System which
                  Datascope sells or leases to third-party users in the regular
                  course of business. The components of the [**] System shall
                  only be resold, leased, rented, licensed or otherwise
                  transferred to third parties for use as a part of a Datascope
                  [**] System as part of a Datascope Patient Monitor or as
                  replacement parts used in Datascope [**] Systems and Datascope
                  shall only sell Aspect approved accessories including cables
                  and sensor products in connection with any Datascope [**]
                  System. During the term of this Agreement, Datascope
                  agrees [**]. However, if Datascope believes that [**], then
                  Datascope may [**]. Datascope [**] Datascope [**] for purposes
                  of this Section 4.1.

         4.2      Aspect Software License.

                  Aspect hereby grants to Datascope a non-exclusive and
                  non-transferable license, without the right to sublicense
                  (except to purchasers of Datascope [**] Systems), during the
                  term of the Agreement to use the Software loaded in the Aspect
                  [**] Kit and related Documentation provided by Aspect solely
                  in connection with operation of the components of Aspect [**]
                  Kit in the Datascope [**] System. All rights granted to
                  Datascope customers to use the Datascope [**] Systems shall
                  survive any termination of this Agreement.

         4.3      Distribution of Aspect BIS Sensors

                  4.3.1    Outside of the United States

                           Aspect hereby grants to Datascope the right to
                           distribute Aspect BIS Sensors solely for use on
                           Datascope [**] Systems sold to Datascope customers
                           outside of the

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                           United States who have purchased BIS solutions
                           exclusively in the form of Datascope [**] Systems.
                           Aspect shall [**] Aspect shall [**] Aspect BIS
                           Sensors for use with [**]. Datascope, [**] Aspect BIS
                           Sensors [**] such Aspect BIS Sensors [**]. Datascope
                           [**] Aspect BIS Sensors [**] Aspect BIS Sensors, [**]
                           Aspect BIS Sensors [**]

                  4.3.2    Within the United States

                           Datascope may sell one starter kit of five (5)
                           sensors with each Datascope [**] System sold to the
                           customer purchasing the corresponding Datascope [**]
                           System. In addition, if Aspect [**] this Agreement
                           [**] Datascope [**] Aspect BIS Sensors [**]
                           Datascope.

                           Datascope may also purchase sensors in the United
                           States for demonstration purposes. Sensors purchased
                           for demonstration use may not be resold to customers.

                  4.3.3    Prices

                           Prices for Aspect BIS Sensors purchased by Datascope
                           hereunder shall be as set forth in Exhibit A (Aspect
                           Products and Purchase Prices).

         4.4      Monitor Cable Development and Production.

                  4.4.1    NRE for any Datascope specific alterations to the
                           Monitor Cable shall be borne by Datascope.

                  4.4.2    Initial development of the Monitor Cable must be done
                           at Aspect's preferred cable vendor [**], with
                           assistance provided by Aspect.

                  4.4.3    Datascope may utilize Aspect's tooling in the
                           production of the cable, with the following
                           conditions:

                           (a)      Aspect retains ownership of all tooling that
                                    is not specifically unique to the Datascope
                                    Monitor Cable.

                           (b)      Aspect has the right to transfer tooling to
                                    another vendor if necessary.

                           (c)      Aspect will provide design files to
                                    Datascope if Datascope desires its own
                                    tooling to produce cables at a different
                                    vendor.

                           (d)      Aspect may [**] Monitor Cable [**] Monitor
                                    Cables. If Datascope [**] Datascope will
                                    [**]

         4.4      System Compatibility.

                  All Datascope Passport 2 and Spectrum systems shipped to
                  locations where the BIS is used (OR, ICU and procedural
                  sedation sites) will have host system software configured to
                  support the Datascope [**] System and will be capable of

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                  accepting Aspect's Bispectral display [**]. Once BIS software
                  is released for the Datascope Passport2 and Spectrum systems,
                  BIS capability, at Datascope's discretion may add BIS
                  capability to its installed base of Datascope Passport2 and
                  Spectrum systems. Datascope Passport 2 and Spectrum comm port
                  that have BIS capability will be marked in a location and size
                  "BIS Ready" as mutually agreed upon.

         4.5      Exclusivity.

                  The Datascope [**] System will be [**] in the [**]. Nothing in
                  this Agreement shall be construed to grant Aspect any license
                  to sell, distribute or license to any third party any
                  Datascope components, including the enabling software and
                  Monitor Cable, in the Datascope [**] System. It is understood
                  that Aspect sells, distributes, and licenses to other third
                  parties both generic and customized Aspect BIS Engines and
                  Aspect [**] Kits to meet the needs of other OEM customers, and
                  nothing in this Agreement shall prohibit Aspect from
                  continuing to sell, distribute, or license these products or
                  components thereof to customers other than Datascope.

5.   SCOPE OF DELIVERY.

         5.1      Purchase Orders.

                  Purchase orders (via Fax, e-mail, other electronic
                  transmission or paper) for Aspect Products to be purchased
                  under this Agreement (the "Orders") must be received by Aspect
                  during the term of this Agreement and must specify a delivery
                  date in accordance with the lead-time schedule outlined below
                  under Section 5.7. All Datascope Purchase Orders shall make
                  reference to the appropriate engineering drawing or
                  manufacturing reference numbers.

         5.2      Order Acknowledgements.

                  Datascope purchase orders that are within Datascope's
                  forecasted quantities and do not include additional terms and
                  conditions other than those included in this agreement shall
                  be accepted by Aspect within [**] days of receipt of the
                  purchase order. If the quantity requested is greater than
                  Datascope's forecasted amount, Aspect will notify Datascope of
                  such and will advise Datascope, within [**] days of the
                  receipt of the purchase order of the time, using reasonable
                  business efforts, that Aspect will need to fill the purchase
                  order.

         5.3      Forecasts.

                  Datascope shall furnish to Aspect a non-binding [**] forecast
                  during the term of this Agreement with the number and type of
                  Aspect Products for which Datascope expects to submit orders
                  for the following [**].

         5.4      Supply of Monitor Cables.

                  Datascope will supply enough Monitor Cables to Aspect, [**] to
                  maintain an inventory sufficient to satisfy a rolling
                  inventory of [**] of cables, including units sufficient to
                  cover yield, service and warranty. Lead times listed in
                  section 5.7 are dependent upon receipt of

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                  cables required to satisfy those orders.

         5.5      Installed Base Reporting.

                  On a [**] basis, Datascope will report units installed during
                  that [**]. In the United States, this report will include
                  number of units installed, date installed and the location by
                  hospital name and city. Outside the US, the report will
                  include number of units installed by country.

         5.6      Cancellation Charges.

                  In the event of the cancellation of any Order by Datascope,
                  Datascope shall be liable for the payment of cancellation
                  charges based on the documented damages (including lost
                  revenues) suffered by Aspect. However, before such damages are
                  documented, Aspect shall use its reasonable efforts to
                  mitigate any damages. Such damages, however, shall not be
                  greater than that shown below based on the number of days
                  prior to scheduled delivery date that written notice of
                  cancellation is received by Aspect, as outlined below:

                [**] weeks prior to acknowledged delivery   [**]
                [**] weeks prior to acknowledged delivery   [**]% of order value
                [**] weeks prior to acknowledged delivery   [**]% of order value
                [**] weeks prior to acknowledged delivery   [**]% of order value
                [**] weeks prior to acknowledged delivery   [**]% of order value

         5.7      Lead Times.

                  Lead times for the Datascope BIS System are expected to be
                  [**] days. Late deliveries are subject to late fees of 1% per
                  month (pro-rated daily). In the event of late deliveries by
                  Aspect, Aspect will also promptly reimburse Datascope for
                  expedited shipment charges that Datascope incurs as a direct
                  result of late shipments of the Aspect [**] Kit from Aspect.
                  [**] with the Monitor Cable, [**]

6.   ROYALTIES AND COMMISSIONS.

         6.1      Commissions on Sales of Aspect BIS Sensors.

                  For each Aspect BIS Sensor sold by Aspect to Datascope
                  customers in the United States for use with Datascope [**]
                  Systems, Aspect shall pay Datascope a commission equal to [**]
                  percent of the net sales revenue realized by Aspect for such
                  Aspect BIS Sensors. Aspect shall pay such commissions to
                  Datascope on a [**] basis. With such [**] payments, Aspect
                  shall provide to Datascope a list of Datascope customers to
                  which such sales were made, the number of sensors sold in that
                  [**], and the revenue realized from the sale of the sensors by
                  Aspect. This [**] payment shall be provided to Datascope no
                  later than 30 days following the end of each [**]. In the
                  event that Aspect's standalone BIS monitors and/or the BIS
                  modules of other manufacturers have also been installed at
                  such sites in addition to Datascope [**] Systems, Datascope
                  will be entitled to a [**]% commission only on BIS Sensor
                  sales intended for use with Datascope [**] Systems. A pro rata
                  determination will be based on the total number of BIS units

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                  of different types installed at such locations during the
                  period. To facilitate such calculations, Datascope will be
                  responsible for providing Aspect with documentation, on a [**]
                  basis, of the total number of Datascope [**] Systems
                  installed, and the dates of installation.

7.   PRICES

         7.1      Purchase Prices.

                  The prices of Aspect Products purchased by Datascope hereunder
                  (the "Purchase Prices"), which are ordered during the term of
                  the Agreement, shall be as set forth in Exhibit A (Aspect
                  Products and Purchase Prices).

         7.2      Customization Costs.

                  Additional cost (both NRE and incremental unit cost) for
                  customization requested by Datascope of the product (mold
                  color, labeling) will be borne by Datascope. Datascope shall
                  be responsible for any charges requested by Datascope
                  associated with scrap of inventory due to any subsequent
                  changes made to customized product.

         7.3      Purchase Price Changes.

                  The Purchase Prices set forth in Exhibit A (Aspect Products
                  and Purchase Prices) shall be reviewed 12 months after first
                  delivery of production units and annually thereafter. In the
                  event materials costs for the Aspect Products increase by more
                  than [**] percent ([**]%), Aspect shall have the right no more
                  than once per year during the term of this Agreement to
                  increase the Purchase Price of the Aspect Products by an
                  equivalent amount by delivering reasonable documentation
                  supporting such increase and by giving Datascope written
                  notice of the increase not less than [**] days prior to the
                  date upon which the increased Purchase Price is to become
                  effective. No Purchase Price increase shall apply to orders
                  for Aspect Products accepted by Aspect prior to or during such
                  [**] day period, which are to be delivered within [**] days of
                  the date of such notice. Notwithstanding anything to the
                  contrary in this Section 6.2, no Purchase Price increase shall
                  apply unless Aspect has used its reasonable efforts to find
                  alternate suppliers of the materials that have increased in
                  cost and, despite exercising such reasonable efforts, was not
                  able to locate such alternate suppliers.

         7.4      [**]
                  In no case shall the [**] Datascope [**] with Aspect [**] this
                  Agreement [**].

         7.5      Taxes.

                  All prices for Aspect Products are exclusive of all federal,
                  state and local taxes, levies and assessments, and Datascope
                  shall be responsible for the payment of all such taxes, levies
                  and/or assessments imposed on Aspect Products purchased and/or
                  licensed by Datascope hereunder, excluding taxes based on
                  Aspect's net income from the transaction. Datascope shall be
                  responsible for providing in a timely manner all
                  documentation, in the nature of exemption certificates or
                  otherwise, necessary to allow Aspect to refrain from
                  collections, such as sales tax,

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                  which it would otherwise be obligated to make.

8.   TERMS OF PAYMENT.

         8.1      Invoices.

                  Datascope shall pay to Aspect the Purchase Price for all
                  Aspect Products shipped hereunder within [**] days after the
                  receipt of Aspect's invoice. Nothing herein shall affect
                  Aspect's right to withhold shipment or otherwise exercise its
                  rights under Section 22 (Termination) hereof in the event of
                  Datascope's failure to make payment when due for Aspect
                  Products delivered to Datascope. Datascope shall have the
                  right to provide Aspect with a specific address to which
                  Aspect will send invoices for Aspect Products purchased under
                  this Agreement.

         8.2      Late Payment Charge.

                  Subject to applicable law, service and/or interest charges not
                  exceeding the lesser of 1% per month or the highest amount
                  permitted by law may, at the election of Aspect, be assessed
                  on amounts past due more than [**] days (that is, more than
                  [**] days after the payment due date as specified in Section
                  8.1). Datascope, however, shall receive a [**] percent ([**]%)
                  discount if payment is made within [**] days of date of
                  invoice.

9.   SHIPMENT AND DELIVERY.

         9.1      Delivery Location. Each shipment must indicate the exact
                  address of the recipient on the outside of the packaging as
                  follows:

                                 Datascope Corp
                               800 MacArthur Blvd
                              Mahwah, NJ 07430 USA
                                 (201) 995-8000

         9.2      Delivery Terms.

                  All shipments hereunder shall be FOB Aspect's Massachusetts
                  point of origin (Incoterms 1990). All Aspect Products shall be
                  deemed delivered and subject to Datascope's dominion and
                  control only when properly packed and ready for shipment to
                  Datascope and placed in the possession of a carrier designated
                  by Datascope. Aspect shall cooperate with Datascope in the
                  documentation and proof of loss claims promptly presented by
                  Datascope to the appropriate carrier and/or insurer.

         9.3      Delivery Date and Date of Dispatch.

                  The requested delivery date shall be specified on the
                  Datascope Purchase Order provided that such delivery date must
                  be at least [**] days after the date Aspect receives the
                  Order; provided, however, that Aspect shall use its reasonable
                  efforts to deliver the Order as close to requested date as
                  reasonably possible (taking other customer demands on Aspect

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                  into account). Aspect shall utilize reasonable efforts to
                  ensure that the order is delivered in accordance with Aspect's
                  order acknowledgement and that the date of dispatch is [**]
                  calendar days prior to the delivery date. Late delivery
                  penalties to Aspect will apply as specified in Section 5.7 of
                  this Agreement.

10.  ACCEPTANCE.

         Any Aspect Product shipped hereunder may be subjected to inspection and
         performance testing by Datascope, to confirm that it functions in
         accordance with Aspect's applicable product specifications in effect at
         the time of delivery of such Aspect Products to Datascope. Datascope
         shall provide written notice to Aspect of the rejection of any such
         Aspect Product within [**] days of the date of receipt of any Aspect
         Product. Aspect shall have [**] days from receipt of a notice from
         Datascope rejecting an Aspect Product either, at its option, to make
         any necessary repairs to the defective Aspect Product or to replace it.
         If Aspect replaces an Aspect Product, Datascope shall dispose of the
         replaced Aspect Product in accordance with Aspect's instructions and at
         Aspect's expense. Datascope's sole remedy for rejected Aspect Products
         shall be limited to prompt repair or replacement of such Aspect
         Products.

11.  WARRANTY.

         11.1     General.

                  Aspect warrants solely to Datascope that Aspect Products
                  (including Software) delivered hereunder shall perform
                  substantially in accordance with the specifications in Exhibit
                  B (Aspect's [**] Kit) and shall be free from defects in
                  materials and workmanship, when given normal, proper and
                  intended usage, for [**] months from the date of shipment of
                  the Datascope [**] System to Datascope end customer site or
                  [**] months from the date of shipment by Aspect to Datascope,
                  whichever is less. This warranty shall not apply to expendable
                  components and supply items, such as, but not limited to,
                  cables (except for failures occurring within [**] days of
                  receipt of shipment), or disposable items such as an Aspect
                  BIS Sensor after the expiration date marked on the Sensor
                  packaging. Aspect shall not have any obligation under this
                  Agreement to make repairs or replacements which are required
                  by normal wear and tear, or which result, in whole or in part,
                  from catastrophe, fault or negligence of Datascope, or anyone
                  claiming through or on behalf of Datascope, or from improper
                  or unauthorized use of Aspect Products, or use of Aspect
                  Products in a manner for which they were not designed, or by
                  causes external to Aspect Products such as, but not limited
                  to, power or air conditioning failure.

         11.2     Warranty Procedures.

                  Datascope shall notify Aspect of any Aspect Products which it
                  believes to be defective during the applicable warranty period
                  and which are covered by the warranties set forth in Section
                  11.1. At Aspect's option, such Aspect Products shall be
                  returned by Datascope

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                  to Aspect's designated facility for examination and testing,
                  or may be repaired on site by Aspect. Aspect shall either
                  repair or replace, within [**] days of receipt by Aspect, any
                  such Aspect Product found to be defective and return these
                  Products to Datascope. Transportation and insurance costs
                  shall be borne by Aspect. Should Aspect's examination and
                  testing not disclose any defect covered by the foregoing
                  warranty, Aspect shall so advise Datascope and dispose of or
                  return the Aspect Product in accordance with Datascope's
                  instructions and at Datascope's expense, and Datascope shall
                  reimburse Aspect for transportation and insurance costs.

         11.3     Repair Warranty.

                  Aspect warrants its repair work and/or replacement parts for
                  the duration of the original warranty period as set forth in
                  Section 11.1 or at least [**] months, whichever is longer.

         11.4     DISCLAIMER OF WARRANTIES.

                  THE PROVISIONS OF THE FOREGOING WARRANTIES ARE IN LIEU OF ANY
                  OTHER WARRANTY, WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL,
                  INCLUDING ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR A
                  PARTICULAR PURPOSE OR NONINFRINGEMENT.

12.  SERVICE AND SUPPORT

         12.1     Service and Support.

                  Datascope shall be responsible for providing installation,
                  customer training, service and support (including repair) to
                  its end customers for the Aspect Products Datascope sells to
                  such customers, and Datascope shall bear all related costs
                  incurred for labor, parts, or travel to perform such service.

         12.2     Service Training.

                  Aspect agrees to provide initial service training to a
                  mutually agreed upon number of Datascope service
                  representatives prior to the market release of the [**]
                  Systems, as well as periodic (typically [**]) ongoing training
                  for existing and new Datascope service personnel.

         12.3     Service Period.

                  For a period of [**] following the last delivery to Datascope
                  of the applicable Aspect Product ordered by Datascope
                  hereunder, Aspect shall use its reasonable efforts to make
                  available repair service (or at Aspect's sole discretion,
                  exchange units for the Aspect Products) for purchase by
                  Datascope and third party users of the Aspect products at
                  Aspect's then-current prices for such repair services and
                  exchange units. After expiry of this [**] period, Aspect may,
                  in its sole discretion, continue to supply repair services
                  (and/or exchange units for the Aspect Products) subject to the
                  mutual written agreement of the Parties.

         12.4     Service Reporting.

                  Aspect shall maintain a complete record of all repair
                  activities performed on any Aspect Products received for

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                  repair.

13.  QUALITY ASSURANCE.

         13.1     Certification Status. Both parties agree to maintain, as
                  applicable, ISO900x or ISO13485, EN460x, European directive
                  93/42/EEC Annex II ("MDD AX-II") certification status and
                  compliance with the U.S. Food and Drug Administrations ("FDA")
                  Quality System Regulation ("QSR"), the European Medical Device
                  Directive ("MDD"), and other appropriate regulations pertinent
                  to the development, manufacturing and marketing of medical
                  products similar to the Aspect Products.

         13.2     Aspect Product Compliance. All Aspect Products sold by Aspect
                  under this Agreement shall fully comply with the above quality
                  requirements and guidelines (MDD AX-II, FDA QSR, etc.)

         13.3     QA and Regulatory Audits. Aspect shall permit Datascope's
                  Quality Assurance department to conduct a reasonable audit of
                  its facilities at a mutually agreed upon date after the date
                  of this Agreement for the purpose of approving its status as
                  an OEM supplier, and reasonable periodic audits thereafter for
                  the purpose of confirming continuing compliance with
                  applicable quality and regulatory requirements and guidelines.
                  Such audits shall be scheduled with at least [**] advance
                  notice during normal business hours and shall not take place
                  more than once per calendar year.

14.  REGULATORY MATTERS.

         14.1     Aspect Products.

                  Aspect shall assume full regulatory responsibility for the
                  Aspect Products, including obtaining and maintaining all
                  applicable governmental authorizations and regulatory
                  approvals required to distribute the Aspect [**] Kit. Both
                  Parties shall work together to develop a regulatory plan which
                  defines precisely what the regulatory and localization
                  requirements are for Datascope. In particular, Aspect shall be
                  responsible for generating its own Device Master Record for
                  the Aspect [**] Kit. It is understood that the Aspect [**] Kit
                  shall be a component of the Datascope [**] System.

         14.2     Datascope [**] System.

                  Datascope shall assume the regulatory responsibility for the
                  combination of the Aspect and Datascope components in the
                  Datascope [**] System. Aspect shall provide commercially
                  reasonable support to Datascope as required in the process of
                  obtaining regulatory approvals by making available to
                  Datascope any required information, data, certificates, or
                  technical files as requested by the regulatory authorities.

         14.3     Product Complaints and Incident Reporting.

                  Datascope and Aspect shall inform each other in writing
                  immediately about any event that may require incident
                  reporting in any country. Datascope and Aspect shall inform
                  each other in

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                  writing within [**] business days of a customer complaint
                  regarding the Datascope [**] System, the Aspect Products, or
                  (outside the United States) Aspect BIS Sensors. Both parties
                  will cooperate and use commercially reasonable efforts to
                  resolve such customer complaints. Closure of any customer
                  complaint relating to the Datascope [**] will occur when
                  Datascope notifies Aspect that the problem is resolved.
                  Closure of any customer complaint relating solely to Aspect
                  Products or Aspect Sensors will occur when Aspect notifies
                  Datascope that the problem is resolved.

         14.5     Delegation.

                  Datascope may at its sole discretion delegate some of the
                  obligations under this Section 14 to its sub-distributors.

         14.6     Traceability.

                  Datascope agrees to maintain traceability through serial
                  number and/or lot code for all Aspect products shipped to
                  customer.

         14.7     Recalls and Payments.

                  In the event that Aspect desires to take a corrective action
                  (including notifications or recalls) with respect to any of
                  the Aspect Products sold to Datascope's customer or an end
                  user that have been incorporated in any of the customer's
                  products and distributed by the customer, and such action (i)
                  is required to comply with applicable laws or regulations,
                  (ii) is determined by Aspect in its discretion for a
                  reasonable business purpose or for safety reasons or (iii) is
                  the result of Aspect's failure to supply Aspect Products that
                  conform with the applicable warranty for such Aspect Products,
                  the party's actions that required such action shall be
                  responsible for the repair or replacement of the Aspect
                  Products without cost to the other party, its Affiliates,
                  distributors and subdistributors. The parties agree to consult
                  with each other to establish a reasonable process for managing
                  the corrective action.

15.  PRODUCT CHANGES; DISCONTINUED PRODUCTS; FUTURE PRODUCTS; CONTINUED SUPPLY.

         15.1     Software Updates.

                  Aspect shall make available to Datascope all future software
                  features and performance improvements to the BIS software and
                  the Aspect [**] Kit.

         15.2     Product Changes

                  Aspect shall have the right, at any time and from time to
                  time, to make substitutions and modifications to Aspect
                  Products, provided such substitutions or modifications shall
                  not materially affect form, fit, function, reliability,
                  serviceability, performance, functional interchangeability or
                  interface capability of Aspect Products and further provided
                  that Aspect attends to and pays for any associated regulatory
                  related to the substitution or modification. In the event that
                  any proposed substitution or modification affects, in Aspect's
                  reasonable

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                  judgment, the form, fit, function, reliability,
                  serviceability, performance, functional interchangeability or
                  interface capability of an Aspect Product, Aspect shall give
                  Datascope written notice of such proposed substitution or
                  modification at least [**] days prior to its taking effect.
                  Datascope, however, shall have the right, during such [**] day
                  period and for [**] days thereafter, to order the Aspect
                  Products without such substitution or modification for
                  delivery up to [**] days after such substitution or
                  modification takes effect. If as the expiration of the [**]
                  day period Datascope wishes to still have the original design
                  Aspect Product available, Aspect will either continue the
                  original design as long as Datascope continues to order said
                  design or provide Datascope with the technology, tooling
                  designs, equipment design and their right to manufacture or
                  have manufactured for it the original design Aspect Product.
                  Aspect shall provide the appropriate verification and
                  validation information for evaluating the effect of the change
                  on the Datascope [**].

         15.3     Discontinued Products.

                  Aspect agrees to notify Datascope in writing not less than
                  [**] months in advance of the discontinuance of any Aspect
                  Products purchased by Datascope. Datascope shall be able to
                  place orders for at least [**] months after receipt of the
                  written notice in any case. In addition, Datascope shall be
                  entitled to determine its lifetime-buy quantities and place a
                  corresponding last purchase order.

         15.4     Future Products.

                  The Aspect Products are designed for use in measuring the
                  effects of anesthetic and sedative agents on the brain during
                  surgery and in the intensive care environment.

                  15.4.1   Aspect has an agreement with Boston Scientific
                           Corporation for an option of exclusive distribution
                           of Aspect BIS Sensors for the procedural sedation
                           market in the United States. If Boston Scientific
                           [**] Aspect BIS Sensors for the [**] Aspect agrees to
                           [**] Datascope [**] Datascope [**] Aspect BIS Sensors
                           [**]

16.  OWNERSHIP AND PROTECTION OF RESULTS.

         16.1     No Transfer of Ownership.

                  It is expressly agreed that neither Aspect nor Datascope shall
                  transfer to the other Party any patent rights, copyrights or
                  other intellectual property of any kind that either Party owns
                  as of the Effective Date of this Agreement.

         16.2     Models, Patterns, Dies, etc.

                  Aspect shall retain the title to and possession of any models,
                  patterns, dies, molds, jigs, fixtures, and other tools made
                  for or obtained in connection with this Agreement and related
                  to the Aspect Products, exclusive of the Datascope owned
                  Monitor Cable molds.

17.  DOCUMENTATION AND TRAINING.

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

         Aspect agrees to provide Datascope with product literature, sales team
         and customer training tools, operations and maintenance manuals, and
         other information and training to enable Datascope to sell and maintain
         Aspect Products.

18.  CONFIDENTIALITY.

         No confidential information disclosed by either Party to the other in
         connection with this Agreement shall be disclosed to any person or
         entity other than the recipient Party's employees and contractors
         directly involved with the recipient Party's use of such information
         who are bound by written agreement to protect the confidentiality of
         such information, and such information shall otherwise be protected by
         the recipient Party from disclosure to others with the same degree of
         care accorded to its own confidential information of like importance.
         In addition, each Party and its representatives shall use the
         confidential information only for the purposes specified under this
         Agreement and such information shall not be used for any other purpose
         without the prior written consent of the disclosing Party. To be
         subject to this provision, information must be delivered in writing and
         designated as proprietary or confidential, or if initially delivered
         orally, must be identified at the time of disclosure, and confirmed in
         writing as confidential within ten (10) days after such oral
         disclosure. Information shall not be subject to this provision if it is
         or becomes a matter of public knowledge without the fault of the
         recipient Party, if it was a matter of written record in the recipient
         Party's files prior to disclosure to it by the other Party, if it was
         or is received by the recipient Party from a third person under
         circumstances permitting its unrestricted disclosure by the recipient
         Party, or if it was independently developed by the recipient Party
         without reference to the confidential information. Upon termination of
         this Agreement, each Party shall promptly destroy all confidential
         information of the other Party in the possession or control of such
         Party and all copies thereof, provided that each Party may retain one
         copy thereof for archival purposes. The obligations under this Section
         16 shall continue for both parties for a period of five (5) years after
         delivery by Aspect to Datascope of the last Aspect Product under this
         Agreement. Datascope is entitled to transmit confidential information
         of Aspect to Datascope subsidiaries and affiliated companies. In such,
         case these subsidiaries and affiliated companies may only use such
         information to the same extent as Datascope is entitled to use such
         information under this Agreement. Datascope shall be responsible if any
         of these subsidiaries and affiliated companies fails to comply with the
         confidentiality provisions of this Agreement.

19.  INDEMNITIES.

         19.1     Indemnification by Aspect.

                  Except as provided below, Aspect shall defend and indemnify
                  Datascope from and against any damages, liabilities, costs and
                  expenses (including reasonable

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                  attorney's fees) arising out of any claim that an Aspect
                  Product infringes a valid patent or copyright in the Territory
                  or misappropriates a trade secret of a third party, provided
                  that (i) Datascope shall have promptly provided Aspect written
                  notice thereof and reasonable cooperation, information, and
                  assistance in connection therewith, and (ii) Aspect shall have
                  sole control and authority with respect to the defense,
                  settlement, or compromise thereof. Should any Aspect Product
                  become, or, in Aspect's opinion, be likely to become the
                  subject of an injunction preventing its use as a contemplated
                  herein, Aspect may, at its option, (1) procure for Datascope
                  the right to continue using such Aspect Product, (2) replace
                  or modify such Aspect Product so that it becomes
                  non-infringing, or, if (1) and (2) are not reasonably
                  available to Aspect, then (3) accept return of the allegedly
                  infringing Aspect Product and refund to Datascope the amount
                  which Datascope has paid to Aspect for such Aspect Product.

                  (a)      Aspect shall have no liability or obligation to
                           Datascope hereunder with respect to any patent,
                           copyright or trade secret infringement claim thereof
                           based upon (i) use of the Aspect Product by Datascope
                           in combination with devices or products not provided
                           by Aspect (ii) use of the Aspect Product in an
                           application or environment for which such Aspect
                           Product was not designed or contemplated, (iii)
                           modifications, alterations or enhancements of the
                           Aspect Product not created by or for Aspect, or (iv)
                           any claims of infringement of a patent, copyright or
                           trade secret in which Datascope or any affiliate of
                           Datascope has an interest. Datascope shall indemnify
                           and hold Aspect harmless from all costs, damages and
                           expenses (including reasonable attorney's fees)
                           arising from any claim enumerated in clauses (i)
                           through (iv) above.

                  (b)      In the event that any claim is brought against
                           Datascope as a result of personal injuries and/or
                           property damages resulting from that portion of the
                           Datascope [**] System developed and manufactured by
                           Aspect, and provided further that such claims do not
                           arise as a result of Datascope or its customer's
                           misuse of the Aspect Products, or Datascope or its
                           customer's use of the Aspect Products in an
                           application for which it was not designed by Aspect,
                           where such claim would not have occurred but for such
                           Datascope or its customer's misuse or Datascope or
                           its customer's use, Aspect agrees that it shall
                           indemnify and hold Datascope and its directors,
                           officers, employees, representatives and agents
                           harmless from and against any damages, liabilities,
                           costs and expenses (including attorneys' and other
                           professional fees and other costs of litigation)
                           arising out of such claim, provided that the
                           procedures set forth in Section 19.3 are followed.

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

         19.2      Indemnification by Datascope.

                  Except as provided below, Datascope shall defend and indemnify
                  Aspect from and against any damages, liabilities, costs and
                  expenses (including reasonable attorney's fees) arising out of
                  any claim that a Datascope Patient Monitor infringes, for
                  reasons other than the incorporation of the Aspect Product
                  within such Datascope Patient Monitor, a valid patent or
                  copyright in the Territory or misappropriates a trade secret
                  of a third party, provided that (i) Aspect shall have promptly
                  provided Datascope written notice thereof and reasonable
                  cooperation, information, and assistance in connection
                  therewith, and (ii) Datascope shall have sole control and
                  authority with respect to the defense, settlement, or
                  compromise thereof.

                  (a)      Datascope shall have no liability or obligation to
                           Aspect hereunder with respect to any patent,
                           copyright or trade secret infringement claim thereof
                           based upon (i) use of the Datascope Patient Monitor
                           by Aspect in combination with devices or products not
                           provided by Datascope, (ii) use of the Datascope
                           Patient Monitor in an application or environment for
                           which such Datascope Patient Monitor was not designed
                           or contemplated, (iii) modifications, alterations or
                           enhancements of the Datascope Patient Monitor not
                           created by or for Datascope, or (iv) any claims of
                           infringement of a patent, copyright or trade secret
                           in which Aspect or any affiliate of Aspect has an
                           interest. Aspect shall indemnify and hold Datascope
                           harmless from all costs, damages and expenses
                           (including reasonable attorney's fees) arising from
                           any claim enumerated in clauses (i) through (iv)
                           above

                  (b)      In the event that any claim is brought against Aspect
                           as a result of personal injuries and/or property
                           damages resulting from the Datascope [**] System, and
                           provided further that such claims do not arise as a
                           result of the defective design or operation of that
                           portion of the Datascope [**] System developed or
                           manufactured by Aspect, Datascope agrees that it
                           shall indemnify and hold Aspect and its directors,
                           officers, employees, representatives and agents
                           harmless from and against any damages, liabilities,
                           costs and expenses (including attorneys' and other
                           professional fees and other costs of litigation)
                           arising out of such claim, provided that the
                           procedures set forth in Section 19.3 are followed.

         19.3     Indemnification Procedures.

                  (a)      In the event that any person intends to claim
                           indemnification pursuant to this Agreement, (an
                           "Indemnitee"), it shall promptly notify the
                           indemnifying Party (the "Indemnitor") in writing of
                           such alleged liability, provided that the failure to
                           promptly notify the Indemnitor shall not relieve the
                           Indemnitor of any obligation under this Agreement
                           except to the extent

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                           such failure to provide prompt notice adversely
                           impairs the Indemnitor's ability to defend against
                           the claim, suit or proceeding.

                  (b)      The Indemnitor shall have the sole right to control
                           the defense and settlement thereof, provided, that
                           (i) the Indemnitor may not consent to imposition of
                           any obligation or restriction on the Indemnitee in
                           any settlement unless mutually agreed among Aspect
                           and Datascope (ii) Indemnitor shall keep Indemnitee
                           fully informed and permit the Indemnitee to
                           participate (at Indemnitee's expense) as the
                           Indemnitee may reasonably request and (iii)
                           Indemnitee may, without affecting its right to
                           indemnity hereunder, defend and settle any such
                           claim, suit or proceeding if Indemnitor declines to
                           defend against such claim, suit or proceeding or
                           Files for Bankruptcy. The Indemnitee shall cooperate
                           with the Indemnitor and its legal representatives in
                           the investigation of any action, claim or liability
                           covered by this Agreement.

                  (c)      The Indemnitee shall not, except at its own cost,
                           voluntarily make any payment or incur any expense
                           with respect to any claim or suit without the prior
                           written consent of Indemnitor, which Indemnitor shall
                           not be required to give, provided that the Indemnitee
                           may, without affecting its right to indemnity
                           hereunder, defend and settle any such claim, suit or
                           proceeding if the Indemnitor declines to take
                           responsibility or Files for Bankruptcy.

20.  TRADEMARKS.

         20.1     Trademarks.

                  (a)      Ownership.

                           Datascope acknowledges and agrees that Aspect is the
                           sole and exclusive owner of all right, title and
                           interest in, or has valid licenses to the trademarks
                           (the "Aspect Trademarks") identified on Exhibit D
                           (Aspect Trademarks). Aspect acknowledges and agrees
                           that Datascope is the sole and exclusive owner of all
                           right, title and interest in and to the trademarks
                           (the "Datascope Trademarks") identified on Exhibit D
                           (collectively the "Aspect and Datascope" Trademarks).
                           Each Party recognizes the value of the other Party's
                           Trademarks and the good will associated with the
                           other Party's Trademarks. Datascope agrees that its
                           use of the Aspect Trademarks and any good will
                           arising therefrom shall inure to the benefit of
                           Aspect. Aspect agrees that its use of the Datascope
                           Trademarks and any good will arising therefrom shall
                           inure to the benefit of Datascope. Nothing contained
                           herein shall create, nor shall be construed as an
                           assignment of, any right, title or interest in or to
                           the Aspect Trademarks to Datascope, or the Datascope
                           Trademarks to Aspect, other than the grant of

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                           the licenses in Section 20.1 (c) below; it being
                           acknowledged and agreed that all other right, title
                           and interest in and to the Aspect Trademarks is
                           expressly reserved by Aspect and its licensors, and
                           all other right, title and interest in and to the
                           Datascope Trademarks is expressly reserved by
                           Datascope. Each Party shall keep the other Party's
                           Trademarks free from all liens, mortgages or other
                           encumbrances. Each Party agrees that it shall not
                           attack or otherwise challenge the title, validity or
                           any other rights of the other Party in or to its
                           Trademarks.

                  (b)      Notice.

                           All Datascope [**] Systems that use the Aspect
                           Trademarks shall be accompanied, where reasonable and
                           appropriate, by a proprietary notice consisting of
                           the following elements:

                           (i) The statement "[insert trademark(s)] is a
                           trademark(s) of [or licensed to] Aspect Medical
                           Systems, Inc.".

                           (ii) Datascope shall include the "(TM)" or "(R)"
                           symbol, as instructed by Aspect, after the first
                           prominent use of the Aspect Trademark in the
                           Datascope Patient Monitor Operators Manual and
                           related materials. Datascope shall have a period of
                           sixty (60) days in which to begin to use the "(R)"
                           symbol in replacement of the "(TM)" symbol upon
                           receiving instructions to do so by Aspect for all new
                           stock of such materials. Datascope may continue to
                           deliver stocked literature before the change becomes
                           effective.

                  (c)      License.

                           Each Party hereby grants to the other a nonexclusive,
                           worldwide, royalty-free license (without the right to
                           sublicense) to use the other Party's Trademarks to
                           designate and promote Aspect Products in conjunction
                           with Datascope [**] Systems. Neither Party shall have
                           any other right to use, display or utilize the other
                           Party's Trademarks for any other purpose or in any
                           other manner.

                  (d)      Quality Standards.

                           (i)      Inspection.

                                    Upon reasonable notice and request, each
                                    Party will furnish to the other samples of
                                    its applicable advertising and promotional
                                    materials as necessary to allow the
                                    requesting Party to monitor compliance with
                                    this Agreement. In addition, upon reasonable
                                    notice and request, each licensee Party will
                                    permit the other

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                                    licensor Party to examine any products
                                    bearing the licensor Party's trademarks to
                                    verify that such .products meet the licensor
                                    Party' quality control standards for such
                                    products. If such products do not meet the
                                    licensor Party' quality control standards,
                                    the licensee Party shall not distribute such
                                    products with the licensor Party's
                                    trademarks.

                           (ii)     Protection and Infringement.

                                    Each Party agrees to cooperate with and
                                    assist the other Party in obtaining,
                                    maintaining, protecting, enforcing and
                                    defending the other Party's proprietary
                                    rights in and to its Trademarks. In the
                                    event that either Party learns of any
                                    infringement, threatened infringement or
                                    passing-off of the other Party's Trademarks
                                    , or that any third party claims or alleges
                                    that the other Party's Trademarks infringe
                                    the rights of the third Party obtaining such
                                    information shall notify the other Party
                                    giving the particulars thereof, and if such
                                    claims or allegations relate to this
                                    Agreement, the Datascope [**], the Aspect
                                    [**] Kit or Aspect Products sold hereunder,
                                    shall provide necessary information and
                                    assistance reasonably requested by such
                                    other Party in the event that such other
                                    Party decides that proceedings should be
                                    commenced.

                  (e)      Termination.

                           In addition to the termination rights set forth in
                           Section 22 hereof, in the event that either Party is
                           in material breach of any provision of this Section
                           20, the non-breaching Party may, upon [**] days
                           written notice, terminate the license granted in
                           Section 20.1 (c) if the breaching Party does not cure
                           such breach or default within such [**] day period.
                           In addition to the provisions of Section 22 hereof,
                           upon termination of the license granted in Section
                           20.1 (c), or upon termination of this Agreement, for
                           whatever cause:

                           (i)      Each Party shall immediately cease and
                                    desist from any further use of the other
                                    Party's Trademarks and any trademarks
                                    confusingly similar thereto, either directly
                                    or indirectly;

                           (ii)     All rights in the Aspect Trademarks granted
                                    to Datascope hereunder shall immediately
                                    revert to Aspect, and all rights in the
                                    Datascope Trademarks granted to Aspect
                                    hereunder shall immediately revert to
                                    Datascope.

                  (f)      Promotional Claims.

                           The general form of any promotional claims by
                           Datascope regarding Aspect's Bispectral

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                           Index technology and/or the integration of Aspect's
                           Bispectral Index technology in Datascope Patient
                           Monitors, and the specific form of the use of
                           Aspect's trade names and trademarks, and of intended
                           use claims regarding Aspect's Bispectral Index
                           technology, in promotional material, advertisement,
                           and/or in written technical literature shall be
                           subject to review and approval by Aspect prior to its
                           publication or display. The general form of any
                           promotional claims by Aspect regarding Datascope's
                           Patient Monitors or the integration of Aspect's
                           Bispectral Index technology in Datascope Patient
                           Monitors, and the specific form of the use of
                           Datascope's trade names and Trademarks, and of
                           intended use claims regarding the Datascope [**]
                           Systems, in promotional material, advertisement,
                           and/or in written technical literature shall be
                           subject to review and approval by Datascope prior to
                           its publication or display.

21.  EXPORT.

         Datascope shall not export, directly or indirectly, Aspect Products
         (including when integrated into a Datascope Patient Monitor) or other
         products, information or materials provided by Aspect hereunder, to any
         country for which the United States requires any export license or
         other governmental approval at the time of export without first
         obtaining such license or approval. It shall be Datascope's
         responsibility to comply with the latest United States export
         regulations, and Datascope shall defend and indemnify Aspect from and
         against any damages, fines, penalties, assessments, liabilities, costs
         and expenses (including reasonable attorneys' fees and court costs)
         arising out of any claim that Datascope Patient Monitors or other
         products, information or materials provided by Aspect hereunder were
         exported or otherwise shipped or transported in violation of applicable
         laws and regulations.

22.  TERM; DEFAULT AND TERMINATION.

         22.1     Term and Renewal.

                  The initial term of this Agreement shall commence on the
                  Effective Date and shall continue for a period of five (5)
                  years following introduction of the Datascope [**] System. On
                  each anniversary date one (1) additional year is added to the
                  term of this Agreement to maintain a five (5) year rolling
                  term unless either Party provides written notice of
                  termination to the other Party at least sixty (60) days prior
                  to the anniversary date.

         22.2     Termination for good cause.

                  (a)      Termination by Aspect.

                           The Agreement may be terminated by Aspect giving [**]
                           prior written notice to Datascope in the event
                           Datascope has not commercially introduced a Datascope

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                           [**] System by [**].

                  (b)      Termination by Datascope.

                           The Agreement may be terminated by Datascope giving
                           [**] prior written notice to Aspect if Aspect has
                           failed to provide an Aspect [**] Kit consistent with
                           the specifications outlined in Exhibit B to Datascope
                           by [**].

                  (c)      Material Competitive Features / Competitive
                           Technologies.

                           (i)      Datascope may terminate this Agreement if
                                    the Aspect [**] Kit does not have material
                                    competitive features for measuring the
                                    hypnotic effects of anesthetic and sedative
                                    agents on the brain. In order to exercise
                                    its rights under this Section 22.2(c),
                                    Datascope must provide [**] prior written
                                    notice to Aspect, specifying in reasonable
                                    detail the material features or capabilities
                                    that are required. Following receipt of such
                                    notification, Aspect shall have [**] to
                                    include such features in the Aspect [**]
                                    Kit. If at the end of such [**] period,
                                    Aspect is unable to do so, Datascope may
                                    terminate the Agreement.

                           (ii)     If Datascope [**], Aspect may [**] with [**]
                                    written notice, [**] to Datascope [**].

         22.3     Events of Default.

                  The following shall constitute events of default under this
                  Agreement:

                  (i)      if either Party assigns this Agreement or any of its
                           rights or obligations hereunder without the prior
                           written consent of the respective other Party,
                           except: (a) as specifically permitted under this
                           Agreement; or (b) in connection with the sale or
                           other transfer of such Party's business to which this
                           Agreement relates (the word "assign" to include,
                           without limiting the generality thereof, a transfer
                           of a majority interest in the Party) or

                  (ii)     if either Party shall neglect or fail to perform or
                           observe any of its obligations to the other Party
                           hereunder, including, without limiting the generality
                           thereof, the timely payment of any sums due, and such
                           failure is not cured within thirty (30) days (ten
                           (10) days in the event of a default in the payment of
                           amounts owed the other Party) after written notice
                           thereof from the other Party; or

                  (iii)    if there is (a) a dissolution, termination of
                           existence, liquidation, insolvency or business
                           failure of either Party, or the appointment of a

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                           custodian or receiver of any part of either Party's
                           property, if such appointment is not terminated or
                           dismissed within thirty (30) days; (b) a composition
                           or an assignment or trust mortgage for the benefit of
                           creditors by either Party; (c) the commencement by
                           either Party of any bankruptcy proceeding under the
                           United States Bankruptcy Code or any other federal or
                           state bankruptcy, reorganization, receivership,
                           insolvency or other similar law affecting the rights
                           of creditors generally; or (d) the commencement
                           against either Party of any proceeding under the
                           United States Bankruptcy Code or any other federal or
                           state bankruptcy, reorganization, receivership,
                           insolvency or other similar law affecting the rights
                           of creditors generally, which proceeding is not
                           dismissed within thirty (30) days ("File for
                           Bankruptcy").

         22.4     Remedies.

                  Upon any event of default, and in addition to any other
                  remedies either Party may have at law or in equity, the
                  non-defaulting Party may terminate the Agreement, cancel any
                  outstanding Order, refuse to make or take further Orders or
                  deliveries, cancel any discount given, and declare all
                  obligations immediately due and payable. Any such termination
                  or other action taken by the non-defaulting Party pursuant to
                  this Section 22.4 shall not relieve the defaulting Party of
                  its obligations hereunder and the non-defaulting Party shall
                  retain all legal and equitable remedies after such
                  termination.

23.  INSURANCE.

         Upon request, Aspect shall provide evidence of product liability,
         general liability and property damage insurance against an insurable
         claim or claims which might or could arise regarding Aspect products
         purchased from Aspect. Such insurance shall contain a minimum limit of
         liability for bodily injury and property damage of not less than
         1,000,000 (one million) US$.

24.  DISPUTE RESOLUTION

         24.1     General.

                  Any dispute, controversy or claim arising out of or relating
                  to this Agreement or any related agreement or the validity,
                  interpretation, breach or termination thereof (a "Dispute"),
                  including claims seeking redress or asserting rights under
                  applicable law, shall be resolved in accordance with the
                  procedures set forth herein. Until completion of such
                  procedures, no Party may take any action not contemplated
                  herein to force a resolution of the Dispute by any judicial or
                  similar process, except to the limited extent necessary to;
                  (i) avoid expiration of a claim that might eventually be
                  permitted hereby; or (ii) obtain interim relief, including
                  injunctive relief, to preserve the status quo or prevent
                  irreparable harm.

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

         24.2     Waiver.

                  In connection with any Dispute, the parties expressly waive
                  and forego any right to (i) punitive, exemplary, statutory,
                  enhanced or similar damages in excess of compensatory damages
                  and (ii) trial by jury.

         24.3     Good Faith Negotiations.

                  Any Dispute relating to this Agreement (a "Dispute") will be
                  resolved first through good faith negotiations between
                  appropriate management-level representatives of each Party
                  having responsibility for the sale or use of products
                  involved.

         24.4     Mediation.

                  If within sixty (60) days the parties are unable to resolve
                  the dispute through good faith negotiation, either Party may
                  submit a Dispute for resolution by mediation pursuant to the
                  Center for Public Resources Model Procedure for Mediation of
                  Business Disputes as then in effect. The mediation shall be
                  conducted in Boston, Massachusetts. Mediation will continue
                  for at least thirty (30) days unless the mediator chooses to
                  withdraw sooner. At the request of either Party, the mediator
                  will be asked to provide an evaluation of the Dispute and the
                  parties' relative positions. Each Party shall bear its own
                  costs of mediation effort.

         24.5     Arbitration.

                  After completion of any mediation effort, a Party may submit
                  the Dispute for resolution by arbitration pursuant to the
                  Non-Administered Arbitration Rules of the Center for Public
                  Resources as in effect on the date hereof, unless the parties
                  agree to adopt such rules as in effect at the time of the
                  arbitration. The arbitral tribunal shall be composed of one
                  arbitrator; and the arbitration shall be conducted in Boston,
                  Massachusetts. If the resolution of the Dispute is not found
                  within the terms of this Agreement, the arbitrator shall
                  determine the Dispute in accordance with the governing law of
                  the Agreement, without giving effect to any conflict of law
                  rules or other rules that might render such law inapplicable
                  or unavailable. The prevailing Party in any arbitration
                  conducted under this Section shall be entitled to recover from
                  the other Party (as part of the arbitral award or order) its
                  reasonable attorneys' fees and other costs of arbitration.

         24.5     Applicable Law.

                  The law applicable to the validity of this arbitration
                  provision, the conduct of the arbitration, the challenge to or
                  enforcement of any arbitral award or order or any other
                  question of arbitration law or procedure shall be governed
                  exclusively by the Federal Arbitration Act, 9 U.S.C. sections
                  1-16; however, the award can be modified or vacated on grounds
                  cited in the Federal Arbitration Act or, if the arbitrator's
                  findings of facts are not supported by substantial evidence or
                  the conclusions of law are erroneous, under the laws of the
                  Commonwealth of Massachusetts. The place of

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                  arbitration shall be in Boston, Massachusetts. The parties
                  agree that the federal and state courts located in the
                  Commonwealth of Massachusetts shall have exclusive
                  jurisdiction over any action brought to enforce this
                  arbitration provision, and each Party irrevocably submits to
                  the jurisdiction of said courts. Notwithstanding the foregoing
                  sentence, either Party may apply to any court of competent
                  jurisdiction, wherever situated, for enforcement of any
                  judgment on an arbitral award.

         24.6     Time Limit.

                  Except as time barred under any applicable statute of
                  limitations of lesser duration, any claim by either Party
                  shall be time-barred unless the asserting Party commences an
                  arbitration proceeding with respect to such claim within two
                  years after the cause of action has accrued.

         24.7     Provisional or Interim Judicial Measures.

                  Notwithstanding any other provision of this Agreement, the
                  parties expressly agree that prior to the first meeting of the
                  arbitrator either shall have the right to apply to any state
                  or federal court in the Commonwealth of Massachusetts or any
                  other court that would otherwise have jurisdiction, for
                  provisional or interim measures.

         24.8     Consolidated Proceedings.

                  Each Party hereby consents to a single, consolidated
                  arbitration proceeding of multiple claims, or claims involving
                  more than two parties. The prevailing Party or parties in any
                  arbitration conducted under this paragraph shall be entitled
                  to recover from the other Party or parties (as part of the
                  arbitral award or order) its or their reasonable attorneys'
                  fees and other reasonable costs of arbitration.

25.  GENERAL PROVISIONS.

         25.1     Force Majeure.

                  In the event that either Party is prevented from performing,
                  or is unable to perform, any of its obligations under this
                  Agreement due to any act of God, fire, casualty, flood, war,
                  strike, lock out, failure of public utilities, injunction or
                  any act, exercise, assertion or requirement of governmental
                  authority, epidemic, destruction of production facilities,
                  insurrection, inability to procure materials, labor,
                  equipment, transportation or energy sufficient to meet
                  manufacturing needs, or any other cause beyond the reasonable
                  control of the Party invoking this provision, and if such
                  Party shall have used its best efforts to avoid such
                  occurrence and minimize its duration and has given prompt
                  written notice to the other Party, then the affected Party's
                  performance shall be excused and the time for performance
                  shall be extended for the period of delay or inability to
                  perform due to such occurrence.

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

         25.2     Publicity.

                  Neither Party shall originate any publicity, news release or
                  other public announcement relating to this Agreement or the
                  existence of an arrangement between the Parties without the
                  prior written approval of the other Party, except as otherwise
                  required by law.

         25.3     Waiver.

                  The waiver by either Party of a breach or a default of any
                  provision of this Agreement by the other Party shall not be
                  construed as a waiver of any succeeding breach of the same or
                  any other provision, nor shall any delay or omission on the
                  part of either Party to exercise or avail itself of any right,
                  power or privilege that it has, or may have hereunder, operate
                  as a waiver of any right, power or privilege by such Party.

         25.4     No Agency.

                  Nothing contained in this Agreement shall be deemed to
                  constitute either Party as the agent or representative of the
                  other Party, or both Parties as joint venturers or partners
                  for any purpose. Neither Party shall be responsible for the
                  acts or omissions of the other Party, and neither Party shall
                  have authority to speak for, represent or obligate the other
                  Party in any way without prior written authority from the
                  other Party.

         25.5     Survival of Obligations.

                  All obligations of either Party under Sections 11 (Warranty),
                  12 (Service and Support), 14 (Regulatory Matters), 16
                  (Ownership and Protection of Results), 18 (Confidentiality),
                  19 (Indemnities), 20 (Trademarks), 24 (Dispute Resolution),
                  and 25.6 (Limitation on Liability) shall survive the
                  expiration or termination of this Agreement and continue to be
                  enforceable.

         25.6     LIMITATION ON LIABILITY.

                  EXCEPT AS PROVIDED IN SECTION 19, EACH PARTY'S LIABILITY
                  ARISING OUT OF THE MANUFACTURE, SALE OR SUPPLYING OF ASPECT
                  PRODUCTS OR THEIR USE OR DISPOSITION, WHETHER BASED UPON
                  WARRANTY, CONTRACT, TORT OR OTHERWISE, SHALL NOT EXCEED ALL
                  AMOUNTS PAID AND PAYABLE BY DATASCOPE TO ASPECT UNDER THIS
                  AGREEMENT. IN NO EVENT SHALL EITHER PARTY BE LIABLE TO THE
                  OTHER PARTY FOR SPECIAL, INCIDENTAL, CONSEQUENTIAL, OR OTHER
                  INDIRECT DAMAGES (INCLUDING, BUT NOT LIMITED TO, LOSS OF
                  PROFITS, LOSS OF DATA OR LOSS OF USE DAMAGES) ARISING OUT OF
                  THE MANUFACTURE, SALE OR SUPPLYING OF ASPECT PRODUCTS.

         25.7     Severability.

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                  In the event that any provision of this Agreement is held by a
                  court of competent jurisdiction to be unenforceable because it
                  is invalid or in conflict with any law of any relevant
                  jurisdiction, the validity of the remaining provisions shall
                  not be affected and the rights and obligations of the Parties
                  shall be construed and enforced as if the Agreement did not
                  contain the particular provisions held to be unenforceable.

         25.8     Governing Law.

                  This Agreement shall be governed by and construed in
                  accordance with the laws of the Commonwealth of Massachusetts,
                  without reference to conflict of laws principles, and shall
                  not be governed by the U.N. Convention on Contracts for the
                  International Sale of Goods.

         25.9     Notices.

                  Any notice or communication with regard to the termination of
                  or changes to this Agreement from one Party to the other shall
                  be in writing and either personally delivered or sent via
                  certified mail, postage prepaid and return receipt requested
                  addressed, to such other Party at the address of such Party
                  specified in this Agreement or such other address as either
                  Party may from time to time designate by notice hereunder.

         25.10    Entire Agreement.

                  This Agreement constitutes the entire agreement between the
                  Parties. No waiver, consent, modification or change of terms
                  of this Agreement shall bind either Party unless in writing
                  signed by both Parties, and then such waiver, consent,
                  modification or change shall be effective only in the specific
                  instance and for the specific purpose given. There are no
                  understandings, agreements, representations or warranties,
                  expressed or implied, not specified herein regarding this
                  Agreement or the Aspect Products purchased and/or licensed
                  hereunder. Only the terms and conditions contained in this
                  Agreement shall govern the transactions contemplated
                  hereunder, notwithstanding any additional, different or
                  conflicting terms which may be contained in any Order or other
                  document provided by one Party to the other. Failure of Aspect
                  to object to provisions contained in any Order or other
                  document provided by Datascope shall not be construed as a
                  waiver of the terms and conditions of this Agreement nor an
                  acceptance of any such provision.

         25.11    Headings.

                  Captions and headings contained in this Agreement have been
                  included for ease of reference and convenience and shall not
                  be considered in interpreting or construing this Agreement.

         25.12    Exhibits:

                  The following Exhibits shall be part of this Agreement:

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                     Exhibit A:  Aspect Products and Purchase Prices

                     Exhibit B:  Specifications: Aspect's [**] Kit

                     Exhibit C:  Contact Persons/Addresses

                     Exhibit D:  Aspect and Datascope Trademarks

         25.13    Beneficiaries.

                  Except for the provisions of Section 19 hereof, which are also
                  for the benefit of the other Persons indemnified, this
                  Agreement is solely for the benefit of the parties hereto and
                  their respective affiliates, successors in interest and
                  permitted assigns and shall not confer upon any other person
                  any remedy, claim, liability, reimbursement or other right in
                  excess of those existing without reference to this Agreement.

         25.14    Assignment.

                  Neither Party may assign or delegate this Agreement or any
                  rights or obligations under this Agreement without the prior
                  written consent of the other, which shall not be unreasonably
                  withheld; provided, however, that Datascope may, without the
                  prior written consent of Aspect, assign and delegate this
                  Agreement and any or all of its rights and obligations
                  hereunder to any of its affiliates, and provided that either
                  party shall have the right to assign this Agreement in
                  connection with a sale of the business of such party to which
                  this Agreement relates.

IN WITNESS WHEREOF, this Agreement has been duly executed as a sealed instrument
as of the date specified above.

Aspect Medical Systems, Inc.        Datascope.

By: /s/ J. Neal Armstrong           By: Unreadable
    -------------------------           ----------------------------

Title: CFO                          Title: President
       -----------------------             -------------------------
        7-30-03                              7-28-03

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                                    EXHIBIT A
                       ASPECT PRODUCTS AND PURCHASE PRICES

A) ASPECT BIS/EEG MODULE KIT:

Price for the Aspect [**]
Kit:  $[**]
Demonstration Aspect [**] Kit:                                    $[**]

Additional incremental NRE and unit cost for customization of the product (i.e.
     Mold color, labeling) will be borne by Datascope.

Aspect and Datascope will agree to the size of the demonstration pool of
     Datascope [**] Systems.

Datascope will be responsible for providing Aspect with documentation, on a [**]
     basis, of the total number of Datascope [**] Systems installed in the
     United States during the [**] just ended, the locations, by zip code, of
     such Datascope [**] Systems and the dates of sale and installation.

B) ASPECT BIS SENSORS

Price for the Aspect BIS Sensors: $[**].

Volume discounts are based on the total volume of sensors purchased. Each
     calendar year pricing levels will be set initially based on the volume of
     sensors [**], with subsequent volume discounts realized as additional
     volume discounts are achieved. The discounted price will apply only to the
     sensors purchased after the volume discount is achieved; it is not
     retroactive to sensors purchased prior:

<TABLE>
<CAPTION>
QUANTITY PER YEAR                     PRICE
<S>                                   <C>
      [**]                            $[**]
      [**]                            $[**]
      [**]                            $[**]
      [**]                            $[**]
</TABLE>

Starter kit of five (5) sensors (of like kind):               $[**]
Demonstration kit of five (5) sensors (of like kind):         $[**]
NOTE:  Demonstration kit sensors cannot be resold by Datascope.
Pricing applicable to [**].

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                                    EXHIBIT B
                         SPECIFICATIONS: ASPECT [**] KIT

                            [ASPECT [**] KIT CHART]

[**]
[**]
         Main Parameters:                   [**]
         Bispectral Index:                  0-100 unitless scale

         USB Interface:                     [**]
         RS-232 Interface:                  [**]
         RS-485 Interface:                  [**]

         Dimensions (main body):            [**]
                                            [**]
         Weight:                            [**]
                                            [**]     [**]
         Cable Length:                      [**]
         Temperature:                       [**]
                                            [**]

         Humidity:                          [**]
                                            [**]

         Pressure:                          [**]
                                            [**]

         Electrical Safety:                 [**]
         Input Impedance:                   [**]

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

         Noise (RTI):                       [**]
         Input Range:                       [**]
         EEG Bandwidth:                     [**]
         A/D Conversion:                    [**]
         Sample Rate:                       [**]
         Patient Leakage:                   [**]

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                                    EXHIBIT C
                            CONTACT PERSONS/ADDRESSES

CONTACT PERSONS AND RESPONSIBILITIES AT ASPECT:

<TABLE>
<CAPTION>
                                                                                EMAIL
                                                                             PHONE NUMBER
    PERSON                  TITLE                  RESPONSIBILITY             FAX NUMBER
===============       =================        ======================  =======================
<S>                   <C>                      <C>                     <C>
Joan Rubin            Director, Global         Contract and Marketing  jrubin@aspectms.com
                      Partnerships
---------------       -----------------        ----------------------  -----------------------
Steve Mesrobian       Manager, OEM             Project Manager         smesrobian@aspectms.com
                      Engineering
---------------       -----------------        ----------------------  -----------------------
Steve Perez           Director, Quality        Quality and Regulatory  sperez@aspectms.com
                      Systems                  Matters
---------------       -----------------        ----------------------  -----------------------
</TABLE>

MAILING ADDRESS:      Aspect Medical Systems, Inc.
                      141 Needham St.
                      Newton, MA 02464
                      USA

CONTACT PERSONS AND RESPONSIBILITIES AT DATASCOPE:

[To be provided by Datascope with thirty (30) days of the date of this Agreement

<TABLE>
<CAPTION>
                                                                                EMAIL
                                                                             PHONE NUMBER
   PERSON                  TITLE                   RESPONSIBILITY             FAX NUMBER
============          ================         =====================   ==========================
<S>                   <C>                      <C>                     <C>
Lesla Orsino          Senior Business          Product Manager,        Lesla_orsino@datascope.com
                      Manager                  Passport 2 & Spectrum   (201) 995-8021
                                                                       fax:  (201) 995-8612
------------          ----------------         ---------------------   --------------------------
Rick Byrd             Senior Principal         Project Manager,        Richard_byrd@datascope.com
                      Engineer                 Passport 2 & Spectrum   (201) 995-8372
------------          ----------------         ---------------------   --------------------------

------------          ----------------         ---------------------   --------------------------
</TABLE>

MAILING ADDRESS:      Datascope Corp
                      800 MacArthur Blvd
                      Mahwah, NJ  07430

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            ASPECT / DATASCOPE OEM DEVELOPMENT AND PURCHASE AGREEMENT

                                    EXHIBIT D
                         ASPECT AND DATASCOPE TRADEMARKS

<TABLE>
<CAPTION>
 ASPECT TRADEMARKS                                             REFERENCE
 -----------------                                             ---------
<S>                                   <C>
Aspect(R)                             Aspect  is a trademark of Aspect Medical
                                      Systems, Inc

A-2000(TM)                            A-2000 is a trademark of Aspect Medical
                                      Systems, Inc.

Bispectral Index(R)                   Bispectral is a registered trademark of Aspect Medical Systems,
                                      Inc.

BIS(R)                                BIS is a registered trademark of Aspect Medical Systems, Inc.

[BIS LOGO]                            BIS logo is a registered trademark of
                                      Aspect Medical Systems, Inc.
</TABLE>

DATASCOPE TRADEMARKS                  REFERENCE

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