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                                                                   EXHIBIT 10.12

                  AMENDMENT TO DEVELOPMENT AND SUPPLY AGREEMENT

         This amendment ("Amendment") is made this 3rd day of November 2003 to
the Development and Supply Agreement (the "Master Collaboration Agreement")
between Biosense Webster, Inc. ("Biosense Webster") and Stereotaxis, Inc.
("Stereotaxis").

PREAMBLE

         Pursuant to this Amendment, Biosense Webster and Stereotaxis set forth
the principal terms and conditions for an expanded strategic alliance for the
development of new technologies focusing on the key role of Biosense Webster's
catheter technology and Stereotaxis' NIOBE System in the integrated digital
"Catheterization lab of the future" through the combination of Stereotaxis'
advanced programmatic digital instrument control technology and Biosense
Webster's advanced catheter technology in electrophysiology mapping and
ablation.

                                    RECITALS

         WHEREAS Stereotaxis and Biosense Webster have pursuant to the Master
Collaboration Agreement agreed to jointly develop a Compatible NIOBE -- CARTO
System and to jointly develop certain associated proprietary, interventional,
disposable, electrophysiology devices and to manufacture, market and sell such
products

         WHEREAS, Stereotaxis and Biosense Webster desire to extend their
alliance under the Master Collaboration Agreement to include collaboration in
respect of the development and commercialization of non-Localized
electrophysiology ablation and mapping comprising devices described in or
pursuant to the Appendix ("Partnered NL Catheters") having the functionality of
non-Localized electrophysiology devices that are products of Biosense Webster
("Biosense Webster NL Catheters") and that are navigable with the NIOBE System;
and

         WHEREAS, Stereotaxis has developed a computerized instrument control
system known as the NIOBE System(TM) that enables navigation utilizing
externally applied magnetic fields of inter alia associated proprietary,
interventional, disposable, electrophysiology devices;

         WHEREAS, Biosense Webster has developed and commercialized an
electrophysiology mapping and Localization system known as the CARTO(TM) system
and associated proprietary, interventional, disposable, electrophysiology
devices; and

         WHEREAS Biosense Webster will contribute to the costs of the
development and commercialization of the Partnered NL Catheters by inter alia
providing development support, manufacturing, engineering and administrative
support, regulatory resources and intellectual property rights and Biosense
Webster will also contribute certain costs allocated to the marketing,
promotions and distribution of products and Stereotaxis will contribute inter
alia intellectual property



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and certain development and regulatory resources, certain supplemental
promotions and marketing as set forth in and pursuant to this Amendment;

NOW THEREFORE, IN CONSIDERATION OF THE MUTUAL PROMISES, COVENANTS AND CONDITIONS
HEREIN, THE PARTIES AGREE AS FOLLOWS:

AMENDMENT

1A. Interpretation: Terms and definitions used in the Master Collaboration
Agreement will have the same meaning in this Amendment unless otherwise
indicated and references herein to this Amendment or provisions thereof include
references to terms of the Master Collaboration Agreement incorporated herein by
reference. Unless expressly provided for herein, the Master Collaboration
Agreement remains in full force and effect. In the event of conflict between
this Amendment and the Master Collaboration Agreement, this Amendment will
control.

1B. For purposes of giving effect to this Amendment, references in the Master
Collaboration Agreement to Daughter Products contained in the definitions
"Components", "Defects" and "Net Revenue" will be taken to include references to
Partnered NL Catheters (as that term is defined in the Amendment) in addition
to Daughter Products.

1C. The definition in the Master Collaboration Agreement of "Daughter Product
Specifications", is amended to include a reference to Partnered NL Catheters and
Additional Partnered NL Catheters in addition to references to Daughter Product
One and Daughter Product Two and Additional Daughter Products.

1D. The definition in the Master Collaboration Agreement of "Technical Failure"
is amended to include a reference to all catheters sold under this Agreement by
Biosense, including Partnered NL Catheters and other Stereotaxis Catheters as
well as the reference to Initial Daughter Products.

1E. Where applicable for purposes of giving effect to Section 2
below of this Amendment, references in Section 7 of the Master Collaboration
Agreement to Parent Products are taken to comprise references to Biosense NL
Catheters

1F. Further Definitions

         (i) "Additional Partnered NL Catheters" shall have the meaning set
forth in Section 12 below.

         (ii) "Amendment Exclusivity Period" shall have the meaning set forth in
Section 5 below.

         (iii) "Biosense NL Catheters" shall have the meaning set forth in the
Recitals above.

         (iv) "Delay Date" shall have the meaning set forth in Section 6 below.

         (v) "High Technology Partnered NL Catheter" shall have the meaning set
forth in Section 2.1 below.


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         (vi) "Partnered NL Catheters" shall have the meaning set forth in the
Recitals above. Upon consultation with Biosense Webster, Stereotaxis shall have
the ability to amend the identification of Partnered NL Catheters at any time
within three (3) months of the signing of this Amendment, such that the
catheters so identified are of similar scope and function as those currently
identified in the Appendix attached hereto.

         (vii) "Partnered NL Catheter Launch Date" shall have the meaning set
forth in Section 5.3 below.

         (viii) "Standard Partnered NL Catheter" shall have the meaning set
forth in Section 2.1 below.

         (ix) "Stereotaxis Catheters" shall mean any interventional
non-Localized electrophysiology mapping or ablation devices that have been
commercialized by Stereotaxis at the Partnered NL Catheter Launch Date (and,
upon regulatory clearance for commercial use, any such devices for which
Stereotaxis has applied for such regulatory clearance prior to such date.)

         (x) "Utilization Management Committee" has the meaning set forth in
Section 7 below.

LICENSE GRANTS

2. Intellectual Property Rights: Section 2.1.1 of the Master Agreement is
amended to include references to Partnered NL Catheters and Stereotaxis
Catheters in addition to Daughter Products. Sections 2.1.3, 2.2.1 and 2.2.3 are
amended to include references to Partnered NL Catheters in addition to Daughter
Products.

3. Development and Distribution Collaboration Regarding Certain Non-Localized
Devices: Sections 3.1.2.3, 3.1.2.4 and 3.1.2.7, 3.3 and 3.4. Sections 4.1
(subject to Section 3 of this Amendment), 4.2.1, 4.3, 4.4.1, 4.4.3, 4.5, Section
6, Section 7, Section 8, Section 9 (subject to Section 6 of this Amendment),
Section 10 and Section 11 of the Master Collaboration Agreement are amended to
include references to Partnered NL. Catheters in addition to references to
Daughter Products and to include references to Additional Partnered NL Catheters
in addition to Additional Daughter Products (in all events as appropriate to
give meaning to this Amendment); and in any event the Parties agree to cooperate
in the same manner (where applicable) as set forth in the Master Collaboration
Agreement in respect of Daughter Products (developed from Parent Products) to
develop and commercialize Partnered NL Catheters (developed from Biosense
Webster NL Catheters) and for purposes of giving effect to the foregoing such
applicable terms of the Master Collaboration Agreement. Biosense Webster
acknowledges and agrees that, in accordance with this Amendment and Sections 3
and 4 of the Master Collaboration Agreement it will inter alia:

         (i) serve as sole manufacturer of the Partnered NL Catheters for
         commercial use;

         (ii) distribute and conduct marketing and promotions in respect of
         Partnered NL Catheters, and will use all reasonable commercial efforts
         in this regard to maximize the sales volume of the Partnered NL
         Catheters; and





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           (iii) coordinate with and provide information to Stereotaxis to an
           extent reasonably required to allow Stereotaxis to develop the
           Partnered NL Catheters.

Without limitation to the foregoing, the average selling price(s) of Partnered
NL Catheter(s) will not be greater than the lesser of: (a) [***] of the average
selling price of corresponding Biosense Webster NL Catheter(s) during the past
[***] months (provided that such pricing is sufficiently profitable in order to
achieve compliance with relevant laws); and (b) in the event that Biosense
Webster is generally regarded in the electrophysiology industry as having exited
the relevant segment of the electrophysiology ablation business, [***] of the
average selling price of corresponding manually navigable non-localized
electrophysiology catheter(s) marketed by a Restricted Party (provided such
catheter(s) are generally regarded in the electrophysiology industry as having a
significant market share) that are available in the marketplace. The Parties
acknowledge that the average selling price of any such Restricted Party
competitive catheters may not be publicly available and agree that they will,
upon written request by either Party, mutually determine in good faith within
one month of such written request a reasonable estimate of such average selling
price.

3.1. During the Term (as defined below), Biosense Webster will provide Biosense
Webster NL Catheters (and at such time as Biosense Webster is manufacturing
Partnered NL Catheters, Partnered NL Catheters) to Stereotaxis, for purposes of
Stereotaxis' development of Partnered NL Catheters and for limited promotions
with NIOBE System customers provide that such promotions will be reasonably
coordinated with Biosense Webster in terms of development, clinical and
promotional activities, the greater of (i) up to 500 units per calendar year; or
(ii) up to 10 units per installed NIOBE System per calendar year (where an
installed NIOBE System comprises any NIOBE System that is commercially
operational during such calendar year); at a transfer price of [***].

3.2. Stereotaxis acknowledges and agrees that it will use all reasonable
commercial efforts to develop the Partnered NL Catheters together with Biosense
Webster and to devote appropriate resources to such development and clinical
activities (which may include, for example, an appropriate subset of such
resources as specified in the current Stereotaxis operating budget for
electrophysiology device development). Stereotaxis will utilize Biosense Webster
as an exclusive subcontractor for Stereotaxis' responsibilities in respect of
development of Partnered NL Catheters on commercially reasonable terms to be
mutually agreed and subject to reasonable budgetary constraints.

4. Revenue Share to Stereotaxis For Partnered NL Catheters: Stereotaxis Revenue
Share will be as follows:

4.1. Where a Partnered NL Catheter comprises a magnetically navigable version
of a Parent Product that is based on highly differentiated technology compared
with competitive products in the marketplace ("High Technology Partnered NL
Catheter") then Stereotaxis' Revenue Share in respect of such High Technology
Partnered NL Catheter shall be the same as is set forth in the Master
Collaboration Agreement for Daughter Products. Without limitation to the
foregoing, examples of High Technology Partnered NL Catheters include
magnetically navigable catheters utilizing Biosense Webster' irrigated catheter
technology;

[*** Indicates portions of this exhibit that have been omitted and filed
separately with the Securities and Exchange Commission pursuant to a request for
confidential treatment.]


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4.1.1. Where a Partnered NL Catheter comprises a magnetically navigable version
of a Parent Product that does not contain a differentiated technology compared
with competitive products in the marketplace, ("Standard Partnered NL Catheter")
then in recognition that the Stereotaxis IP comprised in such Standard Partnered
NL Catheter could provide a degree of differentiation for the Standard Partnered
NL Catheter in the marketplace and of Stereotaxis commitment of resources to
develop such Standard Partnered NL Catheter, Stereotaxis' Revenue Share in
respect of such Standard Partnered NL Catheter will be: (i) the same as provided
for in the Master Collaboration Agreement regarding Daughter Products (excepting
[***]; plus (ii) an additional [***].

4.1.2. In the event that no corresponding Biosense Webster NL Catheter referred
to above is distributed by Biosense Webster or in the event that Biosense
Webster is generally regarded in the electrophysiology industry as having exited
the relevant segment of the electrophysiology ablation business, then the
pricing premium (if any) for the relevant Partnered NL Catheter referred to in
Section 4.1.1 above will be calculated with reference to the average selling
price of corresponding manually navigable non-localized electrophysiology
catheters marketed by a Restricted Party (provided such catheters are generally
regarded in the electrophysiology industry as having a significant market share)
that are available in the marketplace. The Parties acknowledge that the average
selling price of any such Restricted Party competitive catheters may not be
publicly available and agree that they will, upon written request by either
Party, mutually determine in good faith within one month of such written request
a reasonable estimate of such average selling price.

5. Biosense Webster as Manufacturer.

5.1 Biosense Webster will manufacture Partnered NL Catheters used for clinical
trials and research unless it notifies Stereotaxis otherwise in writing and in
such case Stereotaxis will manufacture such Partnered NL Catheters.

5.2 Stereotaxis Catheters used for clinical trials and research will be
manufactured by Stereotaxis unless otherwise agreed in writing by the Parties.

5.3 The Parties agree that Biosense will serve as exclusive manufacturer of
Partnered NL Catheters (and at Biosense written election, Stereotaxis Catheters)
for commercial sale and Section 4.1 of the Master Collaboration Agreement is
amended to include references to Partnered NL Catheters (and where applicable,
Stereotaxis Catheters) in addition to Daughter Products and without limitation,
to the extent required, the Parties agree to fully cooperate in the transfer of
manufacturing

[*** Indicates portions of this exhibit that have been omitted and filed
separately with the Securities and Exchange Commission pursuant to a request for
confidential treatment.]


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know-how in respect of Stereotaxis Catheters from Stereotaxis to Biosense in
advance of commercialization thereof.

5.4 Manufacturing subcontractors that Stereotaxis may utilize to give effect to
this Amendment shall be those that are reasonably acceptable to Biosense
Webster.

6. Certain Amendment Exclusivity: The Parties agree, subject to the terms of
this Amendment, that:

6.1. Certain Amendment Exclusivity During The Term: During the Amendment
Exclusivity Period (as defined below), Stereotaxis will not engage in any
development or commercialization activities with respect to interventional
non-Localized electrophysiology mapping or ablation devices in concert or
cooperation or otherwise with any Restricted Party or other material competitor
to Biosense Webster regarding devices of such type;

6.2. Amendment Exclusivity Period. The Partnered NL Catheter Amendment
Exclusivity Period is six (6) years from the date of this Amendment, provided
that in respect of any Additional Partnered NL Catheter, the Amendment
Exclusivity Period for that catheter will comprise 5 years from the date of
first commercial sale of such Additional Partnered NL Catheter in accordance
with the provisions of this Amendment and provided that such catheters are
commercialized expeditiously in a reasonable commercial manner and in good faith
by the Parties.

6.3. Certain Exclusive Distribution: Except as expressly set forth herein:

6.3.1. Subject to Section 6.3.3 below, until the date of the first commercial
sale of a Partnered NL Catheter in the U.S. ("Partnered NL Catheter Launch
Date"), Stereotaxis will continue its commercialization of interventional
non-Localized electrophysiology mapping and ablation devices;

6.3.2. Subject to Section 6.3.3 below, during the period commencing on the date
of the Partnered NL Catheter Launch Date and ending at the expiration of the
Term, Stereotaxis will not engage in any commercialization activities in respect
of interventional non-Localized electrophysiology mapping or ablation devices;

6.3.3. At its election (by written notice to Stereotaxis) Biosense Webster may
conduct exclusive Marketing and Promotions and Distribution (subject to
Stereotaxis rights under Section 4.2.1.2 of the Master Collaboration Agreement)
of some or all Stereotaxis Catheters (and associated non-exclusive Marketing and
Promotions and Distribution of the Stereotaxis CardioDrive(TM) disposable device
in the manner set out below) in some or all markets prior to the Partnered NL
Catheter Launch Date, provided that Stereotaxis may continue its clinical
development activities in close coordination with Biosense Webster in respect of
the Stereotaxis Catheters during this period (which will include investigational
use of a catheter for an application regardless of whether the catheter has been
cleared for commercial use for any other application in the relevant market)

6.3.4. Upon the Partnered NL Catheter Launch Date, Biosense Webster will
conduct exclusive commercial Marketing and Promotions and Distribution of the
Stereotaxis Catheters (subject to Stereotaxis rights under Section 4.2.1.2 of
the Master Collaboration Agreement).





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6.4. Distribution of Stereotaxis' Catheters

6.4.1. The transfer price paid by Biosense Webster to Stereotaxis for
Stereotaxis Catheters that are manufactured by Stereotaxis shall be as mutually
agreed in writing by the parties on reasonable commercial terms but not to
exceed [***]. Notwithstanding the foregoing, Biosense Webster will be under no
obligation to continue such Marketing and Promotions and sales of any
Stereotaxis Catheter in a market in which an equivalent Partnered NL Catheter is
commercially available (provided that Biosense Webster will fulfill specific
customer orders requesting any such Stereotaxis Catheter thereafter). An example
of equivalency (for purposes of the foregoing only) would be a Partnered NL
Catheter that is a 4mm temperature sensing ablation catheter and a Stereotaxis'
4mm temperature sensing ablation catheter.

6.4.2. Upon the Partnered NL Catheter Launch Date and during the Term, in order
to avoid customer confusion regarding the manner of use of certain devices,
Stereotaxis agrees that Biosense Webster (upon its election) may conduct
Marketing and Promotions and Distribution of the Stereotaxis' CardioDrive(TM)
catheter advancer disposable on a non-exclusive basis, provided that such
Marketing, Promotions and Distribution is solely targeted at the use of such
product in conjunction with Partnered NL Catheters and/or Stereotaxis Catheters,
and in no other fashion, and that such devices will be (again, upon Biosense
Webster election) co-branded by the parties, provided that the foregoing will
not limit Sections 4.4 and 4.5 of the Master Collaboration Agreement.

6.4.3. Biosense Webster may procure such CardioDrive(TM) devices from
Stereotaxis at a transfer price per quarter comprising [***] of the average
selling price to end users of such devices in such quarter (which price will be
estimated in good faith by the parties for purposes of invoicing at the time of
procurement and will be subject to prompt adjustment based upon actual pricing
data when available) and otherwise on relevant terms set forth in the Master
Collaboration Agreement If either: there is no average selling price to end
users; or [***] of the average selling price of the CardioDrive(TM) to end users
is less than [***], then the price to Biosense Webster shall be [***].

6.4.4. In the event there are regulatory agency requirements pertaining to the
Marketing and Promotions and Distribution of the CardioDrive(TM) devices by
Biosense Webster in the manner set out above, then Section 9 of the Master
Collaboration Agreement will be taken to apply to the CardioDrive device in
addition to Partnered NL Catheters.

6.5. Certain Training and Promotions: The Parties will mutually determine in
good faith and cooperate to implement appropriate training programs for the
Biosense Webster non-Localized electrophysiology disposables salesforce and the
Stereotaxis systems and software salesforce in order to facilitate the
Distribution of Partnered NL Catheters in accordance with the terms of this
Amendment.

6.6. Certain Development Conditions: The Parties acknowledge and agree that: (i)
in order to evaluate the suitability of certain candidate interventional
non-Localized electrophysiology mapping

[*** Indicates portions of this exhibit that have been omitted and filed
separately with the Securities and Exchange Commission pursuant to a request for
confidential treatment.]





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or ablation devices as Additional Partnered NL Catheters; and (ii) to ensure
expeditious availability of such candidate devices for non-commercial clinical
use where such expeditious availability is a significant factor in facilitating
adoption or utilization of NIOBE Systems by customers; then Stereotaxis may
during the Term develop such devices and make them available for non-commercial
clinical use in close coordination with Biosense Webster representatives;
provided that Stereotaxis will consult with Biosense Webster regarding such
clinical use and evaluation of the results thereof for purposes of determining
whether such device is nominated as an Additional NL Partnered Catheter.

7. Regulatory: Pursuant to the provisions of Section 9 of the Master
Collaboration Agreement, the Parties will pursue expeditious regulatory approval
of Partnered NL Catheters in the USA and Europe and subject to mutual agreement
in foreign countries (provided that Stereotaxis may in its discretion elect that
the Parties will also pursue regulatory clearance in Japan) and the provisions
related to Marketing, Promotions and Distribution and otherwise as applicable in
this Amendment will apply in respect of such foreign territories; provided
that Stereotaxis, as the Party with primary development responsibility for
Partnered NL Catheters, may elect in its discretion to pursue its own PMA or
other applicable FDA marketing authorization as the filing entity (naming
Biosense Webster as Distributor, as applicable) for any Partnered NL Catheter.
In the event that relevant regulatory approval in the U.S. of a Partnered NL
Catheter comprising a magnetically navigable non-Localized 4mm thermocouple
ablation catheter, or a magnetically navigable non-Localized 8mm thermocouple
ablation catheter or a magnetically navigable non-Localized irrigated catheter
is not achieved by 30 months from the date hereof ("Delay Date"), then either
Party may elect that this Amendment will no longer be of any force or effect,
provided that where at the Delay Date the Parties have reasonable prospects of
obtaining such approval in the near term (to be considered within six (6) months
of the expiration of the thirty (30) month Delay Date expiration), such period
will be extended for an additional 6 months. If at the end of the first six (6)
month extension period, approval is not yet obtained, but it appears the Parties
have reasonable prospects of obtaining such approval within the next six months,
the period will be extended for an additional six (6) months. No further
extensions will be allowed unless the parties agree to such an extension in
writing.

8. Pacing and Other Devices Excluded: For the avoidance of doubt and
notwithstanding anything elsewhere contained in this Amendment, nothing
contained in this Amendment will restrict Stereotaxis in any way in respect of
development and commercialization of: (i) devices used for the delivery of
pacing leads in electrophysiology or comprising such leads or associated with
the placing of any such leads; or (ii) other devices used outside the field of
endovascular ("interventional") non-Localized electrophysiology mapping and
ablation (including without limitation in the fields of surgery, interventional
cardiology, interventional radiology and interventional neuroradiology); or
(iii) accessories to the NIOBE System including without limitation components of
the Stereotaxis' CardioDrive catheter advancement mechanism; and this Amendment
does not relate to or establish any rights or restrictions in respect of such
devices.

8.1. During the Term, at least thirty (30) days (or sixty (60) days in the case
of a Restricted Party) prior to Stereotaxis entering into material and
substantial negotiations regarding a potential agreement for magnetically
enabling interventional devices in cardiology fields outside of non-Localized
electrophysiology and mapping (other than: supply agreements with non-Restricted
Parties related to this field; or the field of delivery of pacing leads)
Stereotaxis agrees to notify

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Biosense Webster in writing, together with a summary description of the proposed
potential agreement that would be the subject of such negotiations ("Initial
Notice"). Stereotaxis herein assures Biosense Webster that any agreement
referred to in this Section 8.1 will provide that such agreement shall be
terminable on reasonable commercial terms following a change of control of
Stereotaxis. Upon request by Biosense Webster given within fifteen (15) days of
the date of such Initial Notice, Stereotaxis and Biosense Webster will discuss
the terms and conditions under which Stereotaxis and Biosense Webster would
enter into an agreement like the proposed potential agreement with a third
party. In the event that Stereotaxis and Biosense Webster have not agreed upon
such terms and conditions within fifteen (15) days (or forty (40) days in the
case of a Restricted Party) after the date Stereotaxis provided the Initial
Notice to Biosense Webster, Stereotaxis will be free to enter into such
agreement with a third party without further obligations to Biosense Webster,
and on any terms that Stereotaxis considers appropriate. It is understood that,
because Stereotaxis will be providing the Initial Notice to Biosense Webster
prior to the commencement of material and substantial negotiations with a third
party, Stereotaxis may not be able to define the entire or exact scope of the
rights and obligations of the potential agreement, and accordingly, so long as
the Initial Notice describes in general terms a product, field or rights that
overlap with the product, field or rights actually negotiated with, or granted
to, a third party, Stereotaxis will be deemed to have satisfied its obligations,
under this Section 6.1; also, it is understood that Stereotaxis need only
provide one (1) such Initial Notice in any twelve (12) month period before
engaging in such material and substantial negotiations with any third party or
parties.

9. Utilization Management:

         i.       The Parties will establish a Utilization Management Committee
                  comprising two appointees from either Party that will, subject
                  to the terms of this Amendment, meet quarterly to review
                  utilization of Partnered NL Catheters and Stereotaxis
                  Catheters with NIOBE Systems and discuss in good faith
                  strategies for mutual cooperation and coordination of the
                  Parties in order to drive increased utilization of NIOBE
                  Systems.

         ii.      Without limitation to the foregoing, the Utilization
                  Management Committee will consider from time to time at the
                  request of either Party whether inclusion of Stereotaxis
                  catheter advancer disposables in the packaging of Partnered NL
                  Catheters would increase utilization of NIOBE Systems in
                  electrophysiology. Where the committee determines that
                  utilization is reasonably likely to be thereby increased, it
                  will recommend to the Parties for their consideration in good
                  faith a proposal for such inclusion of catheter advancer
                  disposables in packaging and an appropriate payment to
                  Biosense Webster

         iii.     In its role of conducting Marketing, Promotions and
                  Distribution of the Partnered NL Catheters and Stereotaxis
                  Catheters pursuant to this Amendment, Biosense Webster will in
                  good faith but in its sole discretion determine any
                  implementation of such strategies (excepting in respect of the
                  potential inclusion of the catheter advancer disposable in
                  packaging of Partnered NL Catheters, which will be determined
                  by Stereotaxis in good faith but in its sole discretion)

         iv.      Either Party may convene a special meeting of the Utilization
                  Management Committee upon 7 days written notice to the other.




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         v.       The Utilization Management Committee will on a quarterly basis
                  (commencing immediately after signing of this Amendment)
                  confer in good faith in order to recommend to Biosense Webster
                  and Stereotaxis goals to be mutually agreed upon for selling
                  Partnered NL Catheters and, where applicable, Stereotaxis
                  Catheters that are mutually agreed in writing by the Parties.

10. Fulfillment of Orders: Biosense Webster will fulfill orders for Partnered NL
Catheters and Stereotaxis Catheters without substitutions and with the same
degree of promptness and customer responsiveness as for Parent Products,
Biosense NL Catheters and other comparable Biosense Webster products. Without
limitation, Biosense will fulfill orders whether such orders are placed directly
with Biosense Webster by a customer or where placed with Biosense Webster
through Stereotaxis on a customer's behalf

10.1. Biosense Webster will utilize such inventory control and management
policies in respect of Partnered NL Catheters as are used in the rest of its
interventional devices business and will accordingly maintain levels of
inventory and parts for Partnered NL Catheters relative to anticipated demand
that are no lower than for such other interventional devices.

10.2. Without limitation to the above provisions of this Section 10, at the
written request of Stereotaxis Biosense Webster agrees to maintain an inventory
cage at its site of stock purchased by Stereotaxis from Biosense to be used as
an emergency inventory supply in case of unforeseen delays in supply and further
to allow Stereotaxis to maintain a similar emergency inventory supply that is
purchased by Stereotaxis at Stereotaxis' own facilities.

10.3. In the event Biosense Webster has not fulfilled any customer order for
Partnered NL Catheters within the period specified in such order (or where no
period is specified, within 7 days) and has not cured such failure within
ninety-six (96) hours ("Cure Period") of written notice from the customer (or
Stereotaxis on a customer's behalf), then Stereotaxis may fulfill such order
from inventory maintained at Stereotaxis' own facility, and Biosense will
reimburse Stereotaxis for its reasonable expenses relating to this transaction.

10.4. Inventory maintained by Stereotaxis in accordance with Sections 10.2
and 10.3 above will be purchased by Stereotaxis at the average selling
prices for such items in the quarter in which such inventory is acquired by
Stereotaxis, which average selling prices will be estimated in good faith by the
Parties for purposes of invoicing and subject to prompt adjustment based on
actual selling price data for the relevant quarter. The Revenue Share to
Stereotaxis for sale of such inventory to customers will be calculated in the
same manner as if such devices had been sold by Biosense Webster in accordance
with this Amendment.

11. Certain Supply of Catheters To Stereotaxis:

11.1 Upon a Change of Control of Stereotaxis, Biosense Webster will cease to
conduct Marketing or Promotions for, or Distribute, Partnered NL Catheters and
Stereotaxis Catheters and will for a period of three years (or until the First
Competitive Sale Date, as defined below, or a period of three years after
termination of this Amendment, whichever is the earlier) after such Change of
Control


<PAGE>

manufacture and supply Stereotaxis with Partnered NL Catheters by fulfilling
orders from Stereotaxis in the same manner as set out in Section 6(i) above and
those provisions of this Amendment required for purpose of giving effect to the
foregoing will continue in force and effect and other provisions of this
Amendment) will no longer be of force or effect except in respect of any
antecedent breach. The transfer price and revenue share to Biosense Webster will
be the same as set forth in the Master Collaboration Agreement relating to any
distribution of Daughter Products by Stereotaxis, provided that in order to
provide incentive to Stereotaxis to expedite occurrence of the First Competitive
Sale Date, a premium of [***] of cost of goods sold to be included in the
calculation of such transfer price will be added in respect of each of the last
three 6-month periods of such three year period. The "First Competitive Sale
Date" means the date following a Change of Control of Stereotaxis upon which
Stereotaxis or its affiliates first sell magnetically navigable
electrophysiology mapping or ablation catheters other than those acquired from
Biosense Webster in accordance with this Section 11.

11.2. Upon expiration of the Term or other termination of this Amendment (other
than via a Change of Control pursuant to Section 11.1 above) and in order to
ensure continuity of supply for customers, Biosense Webster agrees that it will
supply to customers (or in lieu thereof will supply to Stereotaxis for supply to
customers) Partnered NL Catheters on the same terms as set forth in this
Amendment (other than those relating to Amendment Exclusivity and new product
development and subject to relevant minimum order volumes set forth in the
Master Collaboration Agreement) for a 3 year period.

11.3. Certain Supply of Catheters to Customers: Following termination or
expiration of the Master Collaboration Agreement, Biosense Webster will supply
to customers (or in lieu thereof will supply to Stereotaxis for supply to
customers that acquired a Compatible NIOBE System or issued a purchase order for
a Compatible NIOBE System prior to such expiration or termination) Daughter
Products in the same manner as set out in such agreement (including minimum
order volumes) for a period of 3 years.

12. Additional Partnered NL Catheters: For purposes of this Amendment,
Additional Partnered NL Catheters in respect of non-Localized electrophysiology
catheters will have a corresponding meaning to Additional Daughter Products in
respect of Localized electrophysiology catheters. In the same manner as the
Parties may nominate Additional Daughter Products pursuant to the Master
Collaboration Agreement, Stereotaxis has the right to nominate Additional
Partnered NL Catheters (without limitation, based either on Stereotaxis IP or
intellectual property licensed in by Stereotaxis from third parties other than
Restricted Parties), which will then be developed and commercialized in the same
manner as described for Additional Daughter Products under the Master
Collaboration Agreement. In the event Biosense Webster elects not to distribute
any such Additional Partnered NL Catheter in accordance with the foregoing, it
may also decline to manufacture such device, in which case Stereotaxis may
manufacture or procure manufacture of such device (other than through a
Restricted Party).

13. Master Collaboration Agreement: In the event of early termination for any
reason (other than Change of Control) of the Master Collaboration Agreement,
Stereotaxis may elect to terminate this Amendment at any time within 12 months
after any such early termination of the Master Collaboration Agreement.


[*** Indicates portions of this exhibit that have been omitted and filed
separately with the Securities and Exchange Commission pursuant to a request for
confidential treatment.]



<PAGE>




14. Force and Effect of This Amendment: This Amendment will be of no force or
effect unless and until Biosense Webster executes the Purchase Agreement,
Joinder Agreement and Amended Certificate of Incorporation regarding the
investment by Biosense Webster or its Affiliate of $9.5 million in preferred
stock of Stereotaxis. Stereotaxis agrees to provide executed copies of the same
to Biosense Webster for its countersignature immediately upon written notice by
Biosense Webster that it is prepared to execute the same; provided that in the
event that such documents have not been so executed by the parties prior to
December 31, 2003, this Amendment will be of no force or effect.

         IN WITNESS WHEREOF, the Parties hereto have caused this Amendment to be
signed by duly authorized officers or representatives.

STEREOTAXIS, INC.                             BIOSENSE WEBSTER INC.

By: /s/ BEVIL J. HOGG                         By: /s/ RON T. TANAKA
   ------------------------------                ------------------------------
Print Name: BEVIL J. HOGG                     Print Name: RON T. TANAKA
           ----------------------                        ----------------------
Title: CEO/PRESIDENT                          Title: PRESIDENT
      ---------------------------                   ---------------------------
Date: NOVEMBER 3, 2003                        Date: NOVEMBER 3, 2003
     ----------------------------                  ----------------------------

<PAGE>

                                    APPENDIX

                                     [***]

[*** Indicates portions of this exhibit that have been omitted and filed
separately with the Securities and Exchange Commission pursuant to a request for
confidential treatment.]
<PAGE>
                                     [***]

[*** Indicates portions of this exhibit that have been omitted and filed
separately with the Securities and Exchange Commission pursuant to a request for
confidential treatment.]