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                                                                   EXHIBIT 10.27

GE CAPITAL HEALTHCARE FINANCIAL SERVICES

                            MASTER SECURITY AGREEMENT
                             DATED AS OF 08/23/2002

     THIS MASTER SECURITY AGREEMENT is between General Electric Capital
Corporation (together with its successors and assigns, if any, "Secured Party")
and the undersigned Debtor ("Debtor"), Secured Party has a mailing address at
P.O. Box 414, W-490, Milwaukee, WI 53201-0414. Debtor is a Corporation organized
and existing under the laws of the State of Delaware. Debtors mailing address
and chief place of business is 1 Moody Street, Waltham, MA 02453. This Agreement
contains the general terms that apply to the financing of Equipment (defined
below). Additional terms that apply to the Equipment shall be contained on a
schedule ("Schedule") and in the GE Equipment Addendum or the Non-GE Equipment
Addendum, as the case may be.

     1. FINANCING, TERM AND TERMINATION:

          (a) In the case of equipment manufactured by the General Electric
Company or its affiliates ("GE Equipment"), Secured Party agrees to sell to
Debtor and Debtor agrees to purchase from Secured Party the GE Equipment. In the
case of equipment not manufactured by the General Electric Company or its
affiliates ("non-GE Equipment"), Secured Party agrees to finance Debtor's
purchase of the non-GE Equipment. GE Equipment and non-GE Equipment shall be
referred to herein as the "Equipment". All units of Equipment and other
property, and all accessories, upgrades, additions, substitutions, replacement
parts and tools pertaining thereto are further described in any Schedule signed
by both parties.

          (b) This Agreement shall be effective as of the date stated above and,
unless sooner terminated by Secured Party as hereinafter provided, shall
continue until all of Debtor's obligations hereunder or under any Schedule(s)
are fulfilled. The term of each Schedule is as specified in the Schedule and
commences upon the Term Commencement Date (defined in subparagraph (c) below) in
the event of a conflict between provisions of this Agreement and a Schedule, the
provisions of the Schedule shall control.

          (c) The "Term Commencement Date" shall begin on (A) in the case of GE
Equipment, the earlier of (i) five days after the date the Debtor is notified
the Equipment has been assembled and is operating in accordance with the
manufacturer's published performance specifications or (ii) the date the Debtor
first uses the Equipment or (B) in the case of Non-GE Equipment, the date when
Debtor has accepted the Equipment. However, if the GE Equipment's installation
and availability for first use is delayed for any reason for which the Secured
Party is not responsible, the GE Equipment's availability for first use may, at
Secured Party's discretion, be declared to be 30 days after the date the GE
Equipment is delivered.

     2. CREATION OF SECURITY INTEREST: Debtor grants to Secured Party, its
successors and assigns, a security interest in and against the Equipment and in
and against all additions, attachments, accessories and accessions to such
property, all substitutions, replacements or exchanges therefor, and all
insurance and/or other proceeds thereof. This security interest is given to
secure the payment and performance of all debts, obligations and

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liabilities of any kind whatsoever of Debtor to Secured Party, now existing or
arising in the future, from time to time identified on a Schedule and any
renewals, extensions and modifications of such debts, obligations and
liabilities.

     3. MONTHLY INSTALLMENTS/DOWN PAYMENT: Debtor shall pay monthly installments
to Secured Party at its address stated above, except as otherwise directed by
Secured Party. Installments shall be in the amount set forth in the applicable
Schedule and are due in advance beginning on the Term Commencement Date and on
the same day of each consecutive month thereafter. If any down payment (as
stated in the Schedule) is payable, it shall be due when the Debtor signs the
Schedule. The down payment shall be applied in the manner set forth under such
Schedule. Subject to set-off for payments made or expenses incurred by Secured
Party, Secured Party will refund the down payment paid by Debtor with respect to
a Schedule if the Schedule is terminated in writing, before any part of the
Equipment is delivered to the Site, (i) by Secured Party or Debtor as a direct
result of the other's material breach of a material term or condition of that
Schedule or (ii) by mutual written agreement between the parties. If a monthly
installment is not paid within ten days of its due date, Debtor agrees to pay a
late charge of five cents ($.05) per dollar on, and in addition to, the amount
of such installment but not exceeding the lawful maximum, if any. All other
payments received by Secured Party shall first be applied to any accrued late
charge(s) and other monies due Secured Party hereunder and then to any unpaid
installments.

     4. TAXES: If permitted by law, Debtor shall report and pay promptly all
taxes, fees and assessments due, imposed, assessed or levied against any
Equipment (or purchase, ownership, delivery, leasing, possession, use or
operation thereof), this Agreement (or any receipts hereunder), any Schedule,
Secured Party or Debtor by any governmental entity or taxing authority during or
related to the term of this Agreement, including, without limitation, all
license and registration fees, and all sales, use, personal property, excise,
gross receipts, franchise, stamp or other taxes, imposts, duties and charges,
together with any penalties, fines or interest thereon (collectively "Taxes").
Debtor shall have no liability for Taxes imposed by the United States of America
or any state or political subdivision thereof which are on or measured by the
net income of Secured Party. Debtor shall promptly reimburse Secured Party (on
an after tax basis) for any Taxes charged to or assessed against Secured Party.
Debtor shall send Secured Party a copy of each report or return and evidence of
Debtor's payment of Taxes upon request by Secured Party.

     5. REPORTS:

          (a) If any tax or other lien shall attach to any Equipment, Debtor
will notify Secured Party in writing, within ten days after Debtor becomes aware
of the tax or lien. The notice shall include the full particulars of the tax or
lien and the location of such Equipment on the date of the notice.

          (b) Debtor will deliver to Secured Party, Debtor's complete financial
statements, certified by a recognized firm of certified public accountants
within 120 days of the close of each fiscal year of Debtor. Debtor will deliver
to Secured Party copies of Debtor's quarterly financial report certified by the
chief financial officer of Debtor, within 90 days of the close of each fiscal
quarter of Debtor. Debtor will deliver to Secured Party all Forms 10-K and


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10-0, if any, filed with the Securities and Exchange Commission within 30 days
after the date on which they are filed.

          (c) Debtor will promptly notify Secured Party of any change in
Debtor's state of incorporation or organization.

     6. MAINTENANCE:

          (a) Debtor will, at its sole expense, maintain each unit of Equipment
in good operating order and repair, normal wear and tear excepted. The Debtor
shall also maintain the Equipment in accordance with manufacturer's
recommendations. Debtor shall make all alterations or modifications required to
comply with any applicable law, rule or regulation during the term of this
Agreement. If Secured Party requests, Debtor shall affix plates, tags or other
identifying labels showing ownership thereof by Debtor and Secured Party's
security interest.

          (b) Debtor will not attach or install anything on any Equipment that
will impair the originally intended function or use of such Equipment without
the prior written consent of Secured Party. All additions, parts, supplies,
accessories, and equipment ("Additions") furnished or attached to any Equipment
that are not readily removable shall become the property of Secured Party. All
Additions shall be made only in compliance with applicable law. Debtor will not
attach or install any Equipment to or in any other personal or real property
without the prior written consent of Secured Party.

     7. INSURANCE: Debtor agrees at its own expense, to keep the Equipment
insured with companies acceptable to Secured Party for such amounts and against
such hazards as Secured Party may require, including, but not limited to, all
risk physical damage insurance for the Equipment itself, with losses under the
policies payable to Secured Party or its assigns, if any, and liability coverage
for personal injuries, death and/or property damages on terms satisfactory to
Secured Party. Secured Party and/or its officers, agents, employees and/or
successors and/or assigns shall be named as an additional insured under all such
insurance policies with loss payable clauses under said policies payable in
Secured Party's favor, as Secured Party's interest may appear. Said Equipment
shall be insured for not less than its stated replacement value or such other
amount as Secured Party shall specify. Said liability insurance shall be in an
amount of not less than two million dollars ($2,000,000.00) or such other amount
as Secured Party shall specify. Debtor hereby appoints Secured Party as its
attorney-in-fact to make proof of loss and claims for insurance and to make
adjustments with insurers and to receive payment of and execute or endorse all
documents, checks or drafts in connection with payments made with respect to the
insurance policies. Debtor may not make adjustments with insurers except with
Secured Party's prior written consent. The policies will provide that the
insurance may not be altered or canceled by the insurer until after thirty days
written notice to Secured Party. In the event of damage to or loss, secretion,
destruction or theft of the Equipment, or any portion of the Equipment, whether
in whole or in part, Debtor will pay to Secured Party the replacement value of
all Equipment, or of the portion of the Equipment affected if the value and use
of the remainder of the Equipment are not affected at the time of such
occurrence (except the extent that Secured Party receives proceeds of insurance
covering such Equipment). Secured Party may, at Secured Party's option, apply
proceeds of insurance, in whole or in part, (i) to


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repair or comparably replace the Equipment or any portion of it, or (ii) to
satisfy any of Debtor's obligations pursuant to this Agreement or a Schedule.

     8. ACCESS AND REMOVAL:

          (a) The cost of removal and turnover, including all transportation, of
the Equipment in the event of Debtor's default of a Schedule will be at Debtor's
expense. If Debtor makes modifications to the site after the Equipment has been
installed which impede the removal of the Equipment, the cost of removing the
impediments and restoring the site will be at Debtor's expense.

          (b) If, following an event of default, Secured Party exercises its
right to demand that Debtor turn over the Equipment to Secured Party, the
Equipment will be turned over to Secured Party or assigns, in the same condition
and appearance as when received by Debtor (reasonable wear and tear excepted)
and in good working order and condition, operable in accordance with our then
prevailing performance specifications or, in the case of non-GE Equipment, the
supplier's and, if different, the manufacturer's, then prevailing
specifications. All waste material and fluid must be removed from the Equipment
and disposed of by Debtor in accordance with then current waste disposal laws.
If the Equipment is not so turned over, Secured Party, at Debtor's sole expense,
may have the Equipment restored to such a condition if Secured Party so
requires, the units shall be de-installed and crated by an authorized
manufacturer's representative or such other service person as is reasonably
satisfactory to Secured Party.

     9. DEFAULT AND REMEDIES:

          (a) Secured Party may declare this Agreement in default if: (i) Debtor
breaches its obligation to pay monthly installments or any other sum when due
and fails to cure the breach within ten days; (ii) Debtor breaches any of its
insurance obligations under this Agreement; (iii) Debtor breaches any of its
other obligations and fails to cure that breach within 30 days after written
notice from Secured Party; (iv) any representation or warranty made by Debtor in
connection with this Agreement shall be false or misleading in any material
respect; (v) Debtor assigns any of its interests in this Agreement or in the
Equipment without Secured Party's prior consent; (vi) if Debtor or any Guarantor
is a natural person, any death or incompetency of Debtor or such Guarantor;
(vii) a petition is filed by or against Debtor or any Guarantor under any
bankruptcy or insolvency laws and in the event of an involuntary petition, the
petition is not dismissed within 45 days of the filing date; or (x) any material
adverse change occurs in Debtor's financial condition or business operations (or
of any Guarantor) or any material change occurs in the ownership of Debtor; or
(ix) Debtor improperly files an amendment or termination statement relating to a
filed financing statement describing the Equipment. The default declaration
shall apply to all Schedules unless specifically excepted by Secured Party.

          (b) Upon the occurrence of an event of default hereunder, Secured
Party shall have the non-exclusive option to: (i) declare all sums due and
payable; (ii) declare all other amount(s) due Secured Party hereunder
immediately due and payable; (iii) collect from Debtor, on all monies due but
unpaid for more than ten days, a late charge of five cents per dollar on, and


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in addition to, the amount of all such monies, but not exceeding the lawful
maximum; (iv) take possession of the Equipment and remove same from its existing
location(s) without notice to or consent of Debtor; and store and/or dispose (by
public sale or otherwise) of the Equipment at its then existing location(s) at
no charge to Secured Party; (v) sell or lease any or all items of Equipment at
public or private sale or lease at such time or times as Secured Party may
determine and if notice thereof is required by law, any notice in writing of any
such sale or lease by Secured Party to Debtor not less than ten days prior to
the date thereof shall constitute reasonable notice thereof to Debtor; (vi)
otherwise dispose of, hold, use, operate, or keep idle such Equipment, all as
Secured Party, in its sole discretion, may determine; and (vii) assert any other
remedies available to Secured Party at law or in equity (including, without
limitation, under the Uniform Commercial Code).

          (c) After deducting all expenses of retaking, repairing, holding,
transporting, selling and/or reletting the Equipment, the net proceeds (if any)
from such sale or reletting by Secured Party shall be applied against Debtor's
obligation hereunder. The proceeds of any sale, re-lease, or other disposition
(if any) shall be applied in the following priorities: (i) first, to pay all
Secured Party's costs, charges and expenses in taking, removing, holding,
repairing, selling, re-leasing and disposing of the Equipment; (ii) second, to
the extent not previously paid by Debtor (or by a Guarantor of Debtor's
obligations hereunder) to pay Secured Party ail amounts due from Debtor
hereunder; (iii) third, to reimburse to Debtor (or any Guarantor) any sums
previously paid as damages to Secured Party by Debtor (or such Guarantor); and
(iv) lastly, any surplus shall be delivered to Debtor. Secured Party shall have
the right to seek a deficiency from Debtor notwithstanding Secured Party's
repossession or abandonment of the Equipment, or Secured Party's sale or
reletting the Equipment to a third party.

          (d) The foregoing remedies are cumulative, and any or all thereof may
be exercised instead of or in addition to each other or any remedies at law, in
equity, or under statute. Debtor waives notice of sale or other disposition (and
the time and place thereof), and the manner and place of any advertising. Debtor
shall pay Secured Party's actual attorneys fees incurred in connection with the
enforcement, assertion, defense or preservation of Secured Party's rights and
remedies under this Agreement, or if prohibited by law, such lesser sum as may
be permitted. Waiver of any default shall not be a waiver of any other or
subsequent default.

     10. ASSIGNMENT: DEBTOR SHALL NOT SELL, TRANSFER, ASSIGN, ENCUMBER OR SUBLET
ANY EQUIPMENT OR THE INTEREST OF DEBTOR IN THE EQUIPMENT OR THE RIGHTS OR
OBLIGATIONS OF DEBTOR UNDER THIS AGREEMENT WITHOUT THE PRIOR WRITTEN CONSENT OF
SECURED PARTY. Secured Party may, without the consent of Debtor, assign this
Agreement, any Schedule or the right to enter into a Schedule provided that any
such assignment shall not relieve Secured Party of its obligations hereunder.
Debtor agrees that if Debtor receives written notice of an assignment from
Secured Party, Debtor will pay all monthly installments and all other amounts
payable under any assigned Schedule to such assignee or as instructed by Secured
Party. Debtor also agrees to confirm in writing receipt of the notice of
assignment as may be reasonably requested by Secured Party or assignee. Debtor
hereby waives and agrees not to assert against any such assignee any defense,
set-off, recoupment claim or counterclaim which Debtor has or may at any time
have against Secured Party for any reason whatsoever.


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     11. REPRESENTATIONS, WARRANTIES AND COVENANTS OF DEBTOR: Debtor makes each
of the following representations, warranties, and covenants to Secured Party on
the date hereof and on the date of execution of each Schedule.

          (a) Debtor has adequate power and capacity to enter into, and perform
under, this Agreement and all related documents (together, the "Documents").
Debtor is duly qualified to do business wherever necessary to carry on its
present business and operations, including the jurisdiction(s) where the
Equipment is or is to be located.

          (b) The Documents have been duly authorized, executed and delivered by
Debtor and constitute valid, legal and binding agreements, enforceable in
accordance with their terms, except to the extent that the enforcement of
remedies may be limited under applicable bankruptcy and insolvency laws.

          (c) No approval, consent or withholding of objections is required from
any governmental authority or entity with respect to the entry into or
performance by Debtor of the Documents except such as have already been
obtained.

          (d) The entry into and performance by Debtor of the Documents will
not: (i) violate any judgment, order, law or regulation applicable to Debtor or
any provision of Debtor's organizational documents; or (ii) result in any breach
of, constitute a default under or result in the creation of any lien, charge,
security interest or other encumbrance upon any Equipment pursuant to any
indenture, mortgage, deed of trust, bank loan or credit agreement or other
instrument (other than this Agreement) to which Debtor is a party.

          (e) There are no suits or proceedings pending or threatened in court
or before any commission, board or other administrative agency against or
affecting Debtor, which if decided against Debtor will have a material adverse
effect on the ability of Debtor to fulfill its obligations under this Agreement.

          (f) The Equipment is and will remain tangible personal property.

          (g) Each financial statement delivered to Secured Party has been
prepared in accordance with generally accepted accounting principles
consistently applied. Since the date of the most recent financial statement,
there has been no material adverse change in the financial condition of the
Debtor.

          (h) Debtor's exact legal name is as set forth in the last page of this
Agreement and Debtor is and will be at all times validly existing and in good
standing under the laws of the state of its formation (specified in the first
sentence of this Agreement).

          (i) The Equipment will at all times be used for commercial or business
purposes.

          (j) Debtors agrees that the Equipment will be used by Debtor solely in
the conduct of its business and in a manner complying with all applicable laws,
regulations and insurance policies.


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<PAGE>

          (k) Debtor will not move any Equipment from the location specified on
the Schedule, without the prior written consent of Secured Party.

          (l) Debtor will keep the Equipment free and clear of all liens and
encumbrances other than those which result from acts of Secured Party.

     12. USURY SAVINGS: It is the intention of the parties hereto to comply with
any applicable usury laws to the extent that any Schedule is determined to be
subject to such laws. Accordingly, it is agreed that, notwithstanding any
provision to the contrary in any Schedule or this Agreement, in no event shall
any Schedule require the payment or permit the collection of interest in excess
of the maximum amount permitted by applicable law. If any such excess interest
is contracted for, charged or received under any Schedule or this Agreement, or
in the event that all of the principal balance shall be prepaid, so that under
any of such circumstances the amount of interest contracted for, charged or
received under any Schedule or this Agreement shall exceed the maximum amount of
interest permitted by applicable law, then in such event (i) the provisions of
this paragraph shall govern and control, (ii) neither Debtor nor any other
person or entity now or hereafter liable for the payment hereof shall be
obligated to pay the amount of such interest to the extent that it is in excess
of the maximum amount of interest permitted by applicable law, (iii) any such
excess which may have been collected shall be either applied as a credit against
the then unpaid principal balance or refunded to Debtor, at the option of the
Secured Party, and (iv) the effective rate of interest shall be automatically
reduced to the maximum lawful contract rate allowed under applicable law as now
or hereafter construed by the courts having jurisdiction thereof.

     13. LIMITATION OF REMEDIES AND DAMAGES: THE TOTAL LIABILITY OF SECURED
PARTY AND ITS REPRESENTATIVES TO DEBTOR AND DEBTOR'S EXCLUSIVE REMEDY RELATING
TO A SCHEDULE IS LIMITED TO THE MONTHLY INSTALLMENT WHICH IS THE BASIS FOR THE
CLAIM. Debtor agrees that Secured Party and its representatives have no
liability to Debtor for (i) any penal, punitive, special, incidental, or
consequential damages such as lost profit or revenue, (ii) any assistance not
required under the Schedule, or (iii) anything occurring after the end of a
Schedule. Debtor will be barred from any remedy unless Debtor gives Secured
Party prompt written notice of the problem. This is a commercial transaction.
Any claim related to this contract will be covered solely be commercial legal
principles. SECURED PARTY, ITS REPRESENTATIVES AND DEBTOR WILL NOT HAVE ANY
NEGLIGENCE OR OTHER TORT LIABILITY TO THE OTHER ARISING FROM A SCHEDULE.

     14. COMPLIANCE WITH REPORTING RESPONSIBILITIES: Debtor agrees to fully and
accurately account for, and report in any applicable cost reports, all items and
services received from Secured Party under the Agreement, in a way which
complies with all applicable laws and regulations, including the Federal Social
Security Act and implementing regulations relating to Medicare, Medicaid and the
Federal Health Care Programs.

     15. FILING: Debtor will sign and return to Secured Party when requested
such instrument(s) as applicable law requires or permits to give public notice
of Secured Party's interest in the Equipment. In addition, Debtor hereby
authorizes Secured Party to file a financing statement and amendments thereto
describing the Equipment described in any and all Schedules


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<PAGE>

now and hereafter executed pursuant hereto and adding any collateral described
therein and containing any other information required by the applicable Uniform
Commercial Code. Debtor hereby irrevocably appoints Secured Party or its
designee as Debtor's agent and attorney-in-fact to sign such instrument(s) on
Debtor's behalf and to file them.

     16. MISCELLANEOUS:

          (a) DEBTOR AND SECURED PARTY UNCONDITIONALLY WAIVE THEIR RIGHTS TO A
JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING OUT OF THIS
AGREEMENT, ANY OF THE RELATED DOCUMENTS, ANY DEALINGS BETWEEN DEBTOR AND SECURED
PARTY RELATING TO THE SUBJECT MATTER OF THIS TRANSACTION OR ANY RELATED
TRANSACTIONS, AND/OR THE RELATIONSHIP THAT IS BEING ESTABLISHED BETWEEN DEBTOR
AND SECURED PARTY. THE SCOPE OF THIS WAIVER IS INTENDED TO BE ALL ENCOMPASSING
OF ANY AND ALL DISPUTES THAT MAY BE FILED IN ANY COURT. THIS WAIVER IS
IRREVOCABLE. THIS WAIVER MAY NOT BE MODIFIED EITHER ORALLY OR IN WRITING. THE
WAIVER ALSO SHALL APPLY TO ANY SUBSEQUENT AMENDMENTS, RENEWALS, ADDENDA OR
MODIFICATIONS TO THIS AGREEMENT, ANY RELATED DOCUMENTS, OR TO ANY OTHER
DOCUMENTS OR AGREEMENTS RELATING TO THIS TRANSACTION OR ANY RELATED TRANSACTION.
THIS AGREEMENT MAY BE FILED AS A WRITTEN CONSENT TO A TRIAL BY THE COURT.

          (b) Time is of the essence of this Agreement. Secured Party's failure
at any time to require strict performance by Debtor of any of the provisions
hereof shall not waive or diminish Secured Party's right at any other time to
demand strict compliance with this Agreement. If more than one Debtor is named
in this Agreement, the liability of each shall be joint and several. All notices
required to be given hereunder shall be deemed adequately given if sent by
registered or certified malt to the addressee at its address stated herein, or
at such other place as such addressee may have specified in writing. This
Agreement and any addendum, schedule and annexes hereto constitute the entire
agreement of the parties with respect to the subject matter hereof. No prior
proposals, statements, course of dealing, or usage of trade will be a part of
this Agreement. NO VARIATION OR MODIFICATION OF THIS AGREEMENT OR ANY WAIVER OF
ANY OF ITS PROVISIONS OR CONDITIONS SHALL BE VALID UNLESS IN WRITING AND SIGNED
BY AN AUTHORIZED REPRESENTATIVE OF THE PARTIES HERETO.

          (c) If Debtor does not comply with any provision of this Agreement,
Secured Party shall have the right, but shall not be obligated, to effect such
compliance, in whole or in part. All reasonable amounts spent and obligations
incurred or assumed by Secured Party in effecting such compliance shall
constitute an additional installment due to Secured Party. Debtor shall pay the
additional installment within five days after the date Secured Party sends
notice to Debtor requesting payment. Secured Party's effecting such compliance
shall not be a waiver of Debtor's default.


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<PAGE>

          (d) Any provisions in this Agreement, any Schedule, addendum or
amendment hereto that are in conflict with any statute, law or applicable rule
shall be deemed omitted, modified or altered to conform thereto.

          (e) THIS AGREEMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES
HEREUNDER .SHALL IN ALL RESPECTS BE GOVERNED BY AND CONSTRUED IN ACCORDANCE
WITH, THE INTERNAL LAWS OF THE STATE OF MASSACHUSETTS (WITHOUT REGARD TO THE
CONFLICT OF LAWS PRINCIPLES OF SUCH STATE), INCLUDING ALL MATTERS OF
CONSTRUCTION, VALIDITY AND PERFORMANCE, REGARDLESS OF THE LOCATION OF THE
EQUIPMENT.

     IN WITNESS WHEREOF, Debtor and Secured Party have caused this Agreement to
be executed by their duly authorized representatives as of the date first above
written.

SECURED PARTY:                          DEBTOR:

GENERAL ELECTRIC CAPITAL CORPORATION    ATHENAHEALTH, INC.


By:  Illegible                          By: /s/ Carl Byers
    ---------------------------------       ------------------------------------
Name:  Illegible                        Name: Carl Byers
      -------------------------------   Title: CFO
Title: Duly Authorized Signatory


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<PAGE>

GE CAPITAL HEALTHCARE FINANCIAL SERVICES        Internal Contract Ref. # 8522584
                                                Internal Order Ref. # 861-402006

                               EQUIPMENT SCHEDULE
                             DATED AS OF 08/23/2002
                          TO MASTER SECURITY AGREEMENT
                             DATED AS OF 08/23/2002

     This Schedule is executed pursuant to, and incorporates by reference the
terms and conditions of the Master Security Agreement identified above
("Agreement"). Except as provided herein, capitalized terms not defined herein
shall have the meanings assigned to them in the Agreement.

     1. EQUIPMENT: Subject to the terms and conditions of the Agreement, Secured
Party agrees in the case of GE Equipment to sell to Debtor, and in the case of
non-GE Equipment to finance Debtor's purchase of, the Equipment described below
(the "Equipment").

<TABLE>
<CAPTION>
                                                                           MODEL, VIN #, UNIT
                                         SUPPLIER/    FINANCED EQUIPMENT    #, AND/OR TYPE OF
NUMBER OF UNITS          SITE          MANUFACTURER          COST               EQUIPMENT
---------------   ------------------   ------------   ------------------   ------------------
<S>               <C>                  <C>            <C>                  <C>
1                 AthenaHealth, Inc.   Non-GE             $500,000.00      Computer Software
                  1 Moody Street                                           and Hardware
                  Waltham, MA 02453
</TABLE>

     2. TERMS AND INSTALLMENTS:

     A. Term of Schedule: 36 months. The term of this Schedule will commence on
the Term Commencement Date specified in the "Financing, Term and Termination"
section of the Agreement and continue for the term specified immediately above,
subject to and in accordance with the terms and conditions of this Schedule.

     B. Down Payment: $0.00. Debtor's payment of the down payment to Secured
Party will be made on or before execution and return of this Schedule. Secured
Party's retention of the down payment is subject to the "Monthly
Installments/Down Payments" section of the Agreement.

     C. Monthly Installment: 36 Months @ $15,668.41, plus all applicable taxes.
In states assessing sales and use tax, your Monthly Installments will be
adjusted to include the applicable sales and use tax at the same rate that was
used to calculate your Monthly Installments under this Agreement. Debtor's
payment of Monthly Installments to Secured Party will be in accordance with the
"Monthly Installments/Down Payments" section of the Agreement. The interest rate
with respect to this Schedule will be established on the Term Commencement Date.
The interest rate will be equal to 8.48% per annum plus or minus, as applicable,
the number of points that the yield on 3 Year U.S. Treasury Constant Maturities
on the Term Commencement Date is above or below 2.74%, which was established
based on the 3 Year U.S. Treasury Constant Maturities as of the week ending
8/2/2002. The interest rate shall be calculated on the


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basis of a 365-day year and will be charged for each calendar day on which any
principal of the financed Equipment cost is outstanding.

     3. PREPAYMENT PENALTY: The Debtor may prepay in full, but not in part, its
entire indebtedness hereunder upon payment of an additional sum as a premium
equal to the following percentages of the original financed Equipment cost for
the indicated period:

     Prior to the first annual anniversary date of this Schedule: no prepayment
     permitted

     Month thirteen (13) through and including month twenty-four (24) of this
     Schedule: four percent (4%)

     Month twenty-five (25) through and including month thirty-six (36) of this
     Schedule: three percent (3%)

     Month thirty-seven (37) through and including month forty-eight (48) of
     this Schedule: two percent (2%)

     And one percent (1%) thereafter, plus all other sums due hereunder.

     4. AUTODRAFTING:

     A. Debtor hereby authorizes Secured Party to initiate debit entries for
Debtor's payment of the charges which are due periodically under this Schedule
and any service contracts relating to the Equipment and the financial
institution indicated below to debit with the amounts thereof the account listed
below.

Financial Institution Name: Silicon Valley Bank
Financial Institution Address: 3003 Tasman Drive
City: Santa Clara                                   State: CA    Zip: 95054

     B. The following information can be provided from Debtor's check so please
attach a copy of a voided check:

Account Name: Athena Healthcare Incorporated

Nine-digit Financial Institution ID Number: 121140399

Your Financial Institution Account Number: 3300097812

     C. Debtor further authorizes Secured Party to adjust the dollar amount
transferred from Debtor's account to correspond to periodic changes in the
payment due, if any, under the terms of this Schedule.

     D. Debtor hereby authorizes Secured Party to automatically debit all
current or past due property taxes (if applicable).

     E. Rules and Regulations


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<PAGE>

     (i)  Debtor understands that due to the difference in timing between the
          Term Commencement Date and the booking of this Schedule, the initial
          debit may be for more then one periodic charge but will not be more
          than the actual total monthly amounts due at that time.

     (ii) Failure to have adequate funds in Debtor's account shall constitute an
          event of default under this Schedule.

     (iii) Debtor understands that it will continue to receive an invoice each
          month as notification of the amount to be debited from its account.

     (iv) Debtor must provide Secured Party with written notice at least 30 days
          in advance of Debtor's intent to revoke, terminate of modify this
          authorization of the information contained herein. In the event Debtor
          revokes or terminates this authorization, Debtor must remit its
          periodic charges directly to Secured Party at the address specified in
          the Agreement. Failure to pay the periodic charges on or before the
          due date shall constitute an event of default under this Schedule.

     (v)  If a deduction is made in error, Debtor has the right to be
          immediately refunded by Secured Party for the amount of the erroneous
          deduction provided that Debtor provides written notification of the
          erroneous deduction within 15 days after its account statement is
          issued or 45 days after the monies are paid to Secured Party.

     5. DEBTOR DOES FURTHER CERTIFY THAT AS OF THE DATE HEREOF (I) DEBTOR IS NOT
IN DEFAULT UNDER THE AGREEMENT; (II) THE REPRESENTATIONS AND WARRANTIES MADE BY
DEBTOR PURSUANT TO OR UNDER THE AGREEMENT ARE TRUE AND CORRECT ON THE DATE
HEREOF AND (III) DEBTOR HAS REVIEWED AND APPROVES OF THE PURCHASE DOCUMENTS FOR
THE EQUIPMENT, IF ANY.

     6. Any modified or additional terms and conditions of this Schedule are set
forth in the following attachments to this Schedule: ____________.

     7. Except as expressly modified hereby, all terms and provisions of the
Agreement shall remain in full force and effect.

SECURED PARTY:                          DEBTOR:

GENERAL ELECTRIC CAPITAL CORPORATION    ATHENAHEALTH, INC.


By:  Illegible                          By: /s/ Carl Byers
    ---------------------------------       ------------------------------------
Name:  Illegible                        Name: Carl Byers
      -------------------------------   Title: CFO
Title: Duly Authorized Signatory


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<PAGE>

GE CAPITAL HEALTHCARE FINANCIAL SERVICES

                            NON-GE EQUIPMENT ADDENDUM
                             DATED AS OF 08/23/2002
                          TO MASTER SECURITY AGREEMENT
                             DATED AS OF 08/23/2002

     THIS ADDENDUM ("Addendum") is attached and made a part of the above
referenced Master Security Agreement (the "Agreement") between General Electric
Capital Corporation ("Secured Party") and the undersigned Debtor ("Debtor") and
is incorporated by reference into the Agreement. This Addendum modifies and
supplements the Agreement and sets forth additional terms and conditions that
apply to Equipment that has not been manufactured by the General Electric
Company or its affiliates. Any conflict between this Addendum and the Agreement
shall be resolved so as to give effect to the provisions of this Addendum.
Capitalized terms not otherwise defined herein shall have the meaning set forth
in the Agreement.

     1. TRANSPORTATION AND RISK OF LOSS:

          (a) The Equipment will be shipped to the site identified in a Schedule
by the Supplier of the Equipment. Debtor will inform Secured Party of the date
the Equipment is delivered within 5 days of such delivery. Any necessary
assembly or installation will be described in the Schedule. The Debtor agrees to
accept shipment of the Equipment and to cooperate with any assembler to permit
the assembler to complete its task without delay.

          (b) The Debtor or the Supplier will bear responsibility for
transportation and risk of loss of the Equipment at all times. At no time will
Secured Party bear the risk of loss. The use of the term "risk of loss" herein
shall include, without limitation, the entire risk of any loss, theft, damage
to, or destruction of any unit of Equipment from any cause whatsoever.

     2. INDEMNIFICATION: Debtor hereby agrees to indemnify Secured Party, its
agents, employees, successors and assigns (on an after tax basis) from and
against any and all losses, damages, penalties, injuries, claims, actions and
suits, including legal expenses, of whatsoever kind and nature arising out of or
relating to the Equipment or this Agreement, except to the extent the losses,
damages, penalties, injuries, claims, actions, suits or expenses result from
Secured Party's gross negligence or willful misconduct ("Claims"). This
indemnity shall include, but is not limited to, Secured Party's strict liability
in tort and Claims, arising out of (i) the selection, manufacture, purchase,
acceptance or rejection of Equipment, the ownership of Equipment during the term
of this Agreement, and the delivery, lease, possession, maintenance, uses,
condition, return or operation of Equipment (including, without limitation,
latent and other defects, whether or not discoverable by Secured Party or Debtor
and any claim for patent, trademark or copyright infringement or environmental
damage) or (ii) the condition of Equipment sold or disposed of after use by
Debtor or employees of Debtor. Debtor shall, upon request, defend any actions
based on, or arising out of, any of the foregoing. All of Secured Party's
rights, privileges and indemnities contained in this Section 2 shall survive the
expiration or other termination of this Agreement. The rights, privileges and
indemnities contained herein are expressly made for the benefit of, and shall be
enforceable by Secured Party, its successors and assigns.


                                       13

<PAGE>

     3. DISCLAIMER: DEBTOR ACKNOWLEDGES THAT IT HAS SELECTED THE EQUIPMENT
WITHOUT ANY ASSISTANCE FROM SECURED PARTY, ITS AGENTS OR EMPLOYEES, SECURED
PARTY DOES NOT MAKE, HAS NOT MADE, NOR SHALL BE DEEMED TO MAKE OR HAVE MADE, ANY
WARRANTY OR REPRESENTATION, EITHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, WITH
RESPECT TO THE EQUIPMENT LEASED UNDER THIS AGREEMENT OR ANY COMPONENT THEREOF,
INCLUDING, WITHOUT LIMITATION, ANY WARRANTY AS TO DESIGN, COMPLIANCE WITH
SPECIFICATIONS, QUALITY OF MATERIALS OR WORKMANSHIP, MERCHANTABILITY, FITNESS
FOR ANY PURPOSE, USE OR OPERATION, SAFETY, PATENT, TRADEMARK OR COPYRIGHT
INFRINGEMENT, OR TITLE. All such risks, as between Secured Party and Debtor, are
to be borne by Debtor.

     IN WITNESS WHEREOF, Debtor and Secured Party have caused this Addendum to
be executed by their duly authorized representatives as of the date first above
written.

SECURED PARTY:                          DEBTOR:

GENERAL ELECTRIC CAPITAL CORPORATION    ATHENAHEALTH, INC.


By:                                     By: /s/ Carl Byers
    ---------------------------------       ------------------------------------
Name:                                   Name: Carl Byers
      -------------------------------   Title: CFO
Title: Duly Authorized Signatory


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