Exhibit 10.57

MOMENTA PHARMACEUTICALS, INC.

Executive Retention Agreement

THIS EXECUTIVE RETENTION AGREEMENT by and between Momenta Pharmaceuticals, Inc.,
a Delaware corporation (the “Company”), and [     ] (the “Executive”) is
effective as of the date of the last signature on the signature page attached
hereto (the “Effective Date”).

WHEREAS, the Company recognizes that, as is the case with many publicly-held
corporations, the possibility of a change in control of the Company exists and
that such possibility, and the uncertainty and questions which it may raise
among key personnel, may result in the departure or distraction of key personnel
to the detriment of the Company and its stockholders, and

WHEREAS, the Board of Directors of the Company (the “Board”) has determined that
appropriate steps should be taken to reinforce and encourage the continued
employment and dedication of the Company’s key personnel without distraction
from the possibility of a change in control of the Company and related events
and circumstances.

NOW, THEREFORE, as an inducement for and in consideration of the Executive
remaining in [his/her] employ, the Company agrees that the Executive shall
receive the severance benefits set forth in this Agreement in the event the
Executive’s employment with the Company is terminated under the circumstances
described below subsequent to a Change in Control (as defined in Section 1.1).

1.             KEY DEFINITIONS.

As used herein, the following terms shall have the following respective
meanings:

1.1           “CHANGE IN CONTROL” MEANS AN EVENT OR OCCURRENCE SET FORTH IN ANY
ONE OR MORE OF SUBSECTIONS (A) THROUGH (D) BELOW (INCLUDING AN EVENT OR
OCCURRENCE THAT CONSTITUTES A CHANGE IN CONTROL UNDER ONE OF SUCH SUBSECTIONS
BUT IS SPECIFICALLY EXEMPTED FROM ANOTHER SUCH SUBSECTION)

(A)           THE ACQUISITION BY AN INDIVIDUAL, ENTITY OR GROUP (WITHIN THE
MEANING OF SECTION 13(D)(3) OR 14(D)(2) OF THE SECURITIES EXCHANGE ACT OF 1934,
AS AMENDED (THE “EXCHANGE ACT”)) (A “PERSON”) OF BENEFICIAL OWNERSHIP OF ANY
CAPITAL STOCK OF THE COMPANY IF, AFTER SUCH ACQUISITION, SUCH PERSON
BENEFICIALLY OWNS (WITHIN THE MEANING OF RULE 13D-3 PROMULGATED UNDER THE
EXCHANGE ACT) 50% OR MORE OF EITHER (X) THE THEN-OUTSTANDING SHARES OF COMMON
STOCK OF THE COMPANY (THE “OUTSTANDING COMPANY COMMON STOCK”) OR (Y) THE
COMBINED VOTING POWER OF THE THEN-OUTSTANDING SECURITIES OF THE COMPANY ENTITLED
TO VOTE GENERALLY IN THE ELECTION OF DIRECTORS (THE “OUTSTANDING COMPANY VOTING
SECURITIES”); PROVIDED, HOWEVER, THAT FOR PURPOSES OF THIS SUBSECTION (A), THE
FOLLOWING ACQUISITIONS SHALL NOT CONSTITUTE A CHANGE IN CONTROL: (I) ANY
ACQUISITION DIRECTLY FROM THE COMPANY (EXCLUDING AN ACQUISITION PURSUANT TO THE
EXERCISE, CONVERSION OR EXCHANGE OF ANY SECURITY EXERCISABLE FOR, CONVERTIBLE
INTO OR EXCHANGEABLE FOR COMMON STOCK OR VOTING SECURITIES OF THE COMPANY,
UNLESS THE PERSON EXERCISING, CONVERTING OR EXCHANGING SUCH SECURITY ACQUIRED
SUCH SECURITY DIRECTLY FROM THE COMPANY OR AN UNDERWRITER OR AGENT OF THE
COMPANY), (II) ANY ACQUISITION BY THE COMPANY, (III) ANY ACQUISITION BY ANY
EMPLOYEE BENEFIT PLAN (OR RELATED TRUST) SPONSORED OR MAINTAINED BY THE COMPANY
OR ANY CORPORATION CONTROLLED BY THE COMPANY, OR (IV) ANY ACQUISITION BY ANY
CORPORATION PURSUANT TO A TRANSACTION WHICH COMPLIES WITH CLAUSES (I) AND (II)
OF SUBSECTION (C) OF THIS SECTION 1.1; OR

(B)           SUCH TIME AS THE CONTINUING DIRECTORS (AS DEFINED BELOW) DO NOT
CONSTITUTE A MAJORITY OF THE BOARD (OR, IF APPLICABLE, THE BOARD OF DIRECTORS OF
A SUCCESSOR CORPORATION TO THE COMPANY), WHERE THE TERM “CONTINUING DIRECTOR”
MEANS AT ANY DATE A MEMBER OF THE  BOARD (I) WHO WAS A MEMBER OF THE BOARD ON
THE DATE OF THE EXECUTION OF THIS AGREEMENT OR (II) WHO WAS NOMINATED OR ELECTED
SUBSEQUENT TO SUCH DATE BY AT LEAST A MAJORITY OF THE DIRECTORS WHO WERE
CONTINUING DIRECTORS AT THE TIME OF SUCH NOMINATION OR ELECTION OR WHOSE
ELECTION TO THE BOARD WAS RECOMMENDED OR ENDORSED BY AT LEAST A MAJORITY OF THE
DIRECTORS WHO WERE CONTINUING DIRECTORS AT THE

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TIME OF SUCH NOMINATION OR ELECTION; PROVIDED, HOWEVER, THAT THERE SHALL BE
EXCLUDED FROM THIS CLAUSE (II) ANY INDIVIDUAL WHOSE INITIAL ASSUMPTION OF OFFICE
OCCURRED AS A RESULT OF AN ACTUAL OR THREATENED ELECTION CONTEST WITH RESPECT TO
THE ELECTION OR REMOVAL OF DIRECTORS OR OTHER ACTUAL OR THREATENED SOLICITATION
OF PROXIES OR CONSENTS, BY OR ON BEHALF OF A PERSON OTHER THAN THE BOARD; OR

(C)           THE CONSUMMATION OF A MERGER, CONSOLIDATION, REORGANIZATION,
RECAPITALIZATION OR STATUTORY SHARE EXCHANGE INVOLVING THE COMPANY OR A SALE OR
OTHER DISPOSITION OF ALL OR SUBSTANTIALLY ALL OF THE ASSETS OF THE COMPANY IN
ONE OR A SERIES OF TRANSACTIONS (A “BUSINESS COMBINATION”), UNLESS, IMMEDIATELY
FOLLOWING SUCH BUSINESS COMBINATION, EACH OF THE FOLLOWING TWO CONDITIONS IS
SATISFIED: (I) ALL OR SUBSTANTIALLY ALL OF THE INDIVIDUALS AND ENTITIES WHO WERE
THE BENEFICIAL OWNERS OF THE OUTSTANDING COMPANY COMMON STOCK AND OUTSTANDING
COMPANY VOTING SECURITIES IMMEDIATELY PRIOR TO SUCH BUSINESS COMBINATION
BENEFICIALLY OWN, DIRECTLY OR INDIRECTLY, MORE THAN 50% OF THE THEN-OUTSTANDING
SHARES OF COMMON STOCK AND THE COMBINED VOTING POWER OF THE THEN-OUTSTANDING
SECURITIES ENTITLED TO VOTE GENERALLY IN THE ELECTION OF DIRECTORS,
RESPECTIVELY, OF THE RESULTING OR ACQUIRING CORPORATION IN SUCH BUSINESS
COMBINATION (WHICH SHALL INCLUDE, WITHOUT LIMITATION, A CORPORATION WHICH AS A
RESULT OF SUCH TRANSACTION OWNS THE COMPANY OR SUBSTANTIALLY ALL OF THE
COMPANY’S ASSETS EITHER DIRECTLY OR THROUGH ONE OR MORE SUBSIDIARIES) (SUCH
RESULTING OR ACQUIRING CORPORATION IS REFERRED TO HEREIN AS THE “ACQUIRING
CORPORATION”) IN SUBSTANTIALLY THE SAME PROPORTIONS AS THEIR OWNERSHIP,
IMMEDIATELY PRIOR TO SUCH BUSINESS COMBINATION, OF THE OUTSTANDING COMPANY
COMMON STOCK AND OUTSTANDING COMPANY VOTING SECURITIES, RESPECTIVELY; AND (II)
NO PERSON (EXCLUDING ANY EMPLOYEE BENEFIT PLAN (OR RELATED TRUST) MAINTAINED OR
SPONSORED BY THE COMPANY OR BY THE ACQUIRING CORPORATION) BENEFICIALLY OWNS,
DIRECTLY OR INDIRECTLY, 50% OR MORE OF THE THEN OUTSTANDING SHARES OF COMMON
STOCK OF THE ACQUIRING CORPORATION, OR OF THE COMBINED VOTING POWER OF THE
THEN-OUTSTANDING SECURITIES OF SUCH CORPORATION ENTITLED TO VOTE GENERALLY IN
THE ELECTION OF DIRECTORS (EXCEPT TO THE EXTENT THAT SUCH OWNERSHIP EXISTED
PRIOR TO THE BUSINESS COMBINATION); OR

(D)           APPROVAL BY THE STOCKHOLDERS OF THE COMPANY OF A COMPLETE
LIQUIDATION OR DISSOLUTION OF THE COMPANY.

1.2           “CHANGE IN CONTROL DATE” MEANS THE FIRST DATE DURING THE TERM (AS
DEFINED IN SECTION 2) ON WHICH A CHANGE IN CONTROL OCCURS.  ANYTHING IN THIS
AGREEMENT TO THE CONTRARY NOTWITHSTANDING, IF (A) A CHANGE IN CONTROL OCCURS,
(B) THE EXECUTIVE’S EMPLOYMENT WITH THE COMPANY IS TERMINATED PRIOR TO THE DATE
ON WHICH THE CHANGE IN CONTROL OCCURS, AND (C) IT IS REASONABLY DEMONSTRATED BY
THE EXECUTIVE THAT SUCH TERMINATION OF EMPLOYMENT (I) WAS AT THE REQUEST OF A
THIRD PARTY WHO HAS TAKEN STEPS REASONABLY CALCULATED TO EFFECT A CHANGE IN
CONTROL OR (II) OTHERWISE AROSE IN CONNECTION WITH OR IN ANTICIPATION OF A
CHANGE IN CONTROL, THEN FOR ALL PURPOSES OF THIS AGREEMENT THE “CHANGE IN
CONTROL DATE” SHALL MEAN THE DATE IMMEDIATELY PRIOR TO THE DATE OF SUCH
TERMINATION OF EMPLOYMENT.

1.3           “CAUSE” MEANS (A) A GOOD FAITH FINDING BY NO FEWER THAN TWO-THIRDS
OF THE MEMBERS OF THE BOARD (EXCLUDING THE EXECUTIVE, IF APPLICABLE) OF (I) THE
EXECUTIVE’S FAILURE TO (1) PERFORM REASONABLY ASSIGNED LAWFUL DUTIES OR (2)
COMPLY WITH A LAWFUL INSTRUCTION OF THE BOARD, CHIEF EXECUTIVE OFFICER OR SUCH
OTHER EXECUTIVE OFFICER WITH DIRECT SUPERVISORY AUTHORITY OVER THE EXECUTIVE SO
LONG AS, IN THE CASE OF (2), THE INSTRUCTION IS CONSISTENT WITH THE SCOPE AND
RESPONSIBILITIES OF THE EXECUTIVE’S POSITION, OR (II) THE EXECUTIVE’S
DISHONESTY, WILLFUL MISCONDUCT OR GROSS NEGLIGENCE, OR (III) THE EXECUTIVE’S
SUBSTANTIAL AND MATERIAL FAILURE OR REFUSAL TO PERFORM ACCORDING TO, OR TO
COMPLY WITH, THE POLICIES, PROCEDURES OR PRACTICES ESTABLISHED BY THE COMPANY OR
THE BOARD AND, IN THE CASE OF (I) OR (III), THE EXECUTIVE HAS HAD TEN (10) DAYS
WRITTEN NOTICE TO CURE HIS FAILURE TO SO PERFORM OR COMPLY; OR (B) THE
EXECUTIVE’S INDICTMENT, OR THE ENTERING OF A GUILTY PLEA OR PLEA OF “NO CONTEST”
WITH RESPECT TO A FELONY OR ANY CRIME INVOLVING MORAL TURPITUDE.

1.4           “GOOD REASON” MEANS THE OCCURRENCE, WITHOUT THE EXECUTIVE’S
WRITTEN CONSENT, OF ANY OF THE EVENTS OR CIRCUMSTANCES SET FORTH IN CLAUSES (A)
THROUGH (D) BELOW, PROVIDED, HOWEVER, THAT AN EVENT DESCRIBED IN CLAUSES (A)
THROUGH (D) BELOW SHALL NOT CONSTITUTE GOOD REASON UNLESS IT IS COMMUNICATED IN
WRITING IN ACCORDANCE WITH SECTION 7, WITHIN 90 DAYS OF THE EVENT GIVING RISE TO
THE CLAIM, BY THE EXECUTIVE TO THE BOARD OR ITS SUCCESSOR AND UNLESS IT IS NOT
CORRECTED BY THE COMPANY OR ITS SUCCESSOR AND THE EXECUTIVE HAS NOT BEEN
REASONABLY COMPENSATED FOR ANY LOSS OR DAMAGES RESULTING THEREFROM WITHIN THIRTY
(30) DAYS OF THE COMPANY’S RECEIPT OF SUCH WRITTEN NOTICE:

(A)           THE ASSIGNMENT TO THE EXECUTIVE OF DUTIES INCONSISTENT IN ANY
MATERIAL RESPECT WITH THE EXECUTIVE’S POSITION (INCLUDING STATUS, OFFICES,
TITLES AND REPORTING REQUIREMENTS), AUTHORITY OR RESPONSIBILITIES,

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OR ANY OTHER ACTION OR OMISSION BY THE COMPANY WHICH RESULTS IN A MATERIAL
DIMINUTION IN SUCH POSITION, AUTHORITY OR RESPONSIBILITIES;

(B)           THE BOARD REQUIRING THE EXECUTIVE TO ENGAGE IN UNLAWFUL CONDUCT;

(C)           A MATERIAL REDUCTION IN THE EXECUTIVE’S BASE SALARY; OR

(D)           A CHANGE BY THE COMPANY IN THE LOCATION AT WHICH THE EXECUTIVE
PERFORMS [HIS/HER] PRINCIPAL DUTIES FOR THE COMPANY TO A NEW LOCATION THAT IS
BOTH (I) OUTSIDE A RADIUS OF 50 MILES FROM THE EXECUTIVE’S PRINCIPAL RESIDENCE
AND (II) MORE THAN 30 MILES FROM THE LOCATION AT WHICH THE EXECUTIVE PERFORMED
HIS PRINCIPAL DUTIES FOR THE COMPANY.

The Executive’s right to terminate [his/her] employment for Good Reason shall
not be affected by [his/her] incapacity due to physical or mental illness.

1.5           “DISABILITY” MEANS THE EXECUTIVE’S ABSENCE FROM THE FULL-TIME
PERFORMANCE OF THE EXECUTIVE’S DUTIES WITH THE COMPANY FOR 180 CONSECUTIVE
CALENDAR DAYS AS A RESULT OF INCAPACITY DUE TO MENTAL OR PHYSICAL ILLNESS WHICH
IS DETERMINED TO BE TOTAL AND PERMANENT BY A PHYSICIAN SELECTED BY THE COMPANY
OR ITS INSURERS AND ACCEPTABLE TO THE EXECUTIVE OR THE EXECUTIVE’S LEGAL
REPRESENTATIVE.

2.             TERM OF AGREEMENT.  THIS AGREEMENT, AND ALL RIGHTS AND
OBLIGATIONS OF THE PARTIES HEREUNDER, SHALL TAKE EFFECT UPON THE EFFECTIVE DATE
AND SHALL EXPIRE UPON THE FIRST TO OCCUR OF (A) THE EXPIRATION OF THE TERM (AS
DEFINED BELOW) IF A CHANGE IN CONTROL HAS NOT OCCURRED DURING THE TERM, (B) THE
TERMINATION OF THE EXECUTIVE’S EMPLOYMENT WITH THE COMPANY PRIOR TO THE CHANGE
IN CONTROL DATE, (C) THE DATE 12 MONTHS AFTER THE CHANGE IN CONTROL DATE, IF THE
EXECUTIVE IS STILL EMPLOYED BY THE COMPANY AS OF SUCH LATER DATE, OR (D) THE
FULFILLMENT BY THE COMPANY OF ALL OF ITS OBLIGATIONS UNDER SECTIONS 4 AND 5.2 IF
THE EXECUTIVE’S EMPLOYMENT WITH THE COMPANY TERMINATES WITHIN 12 MONTHS
FOLLOWING THE CHANGE IN CONTROL DATE.  “TERM” SHALL MEAN THE PERIOD COMMENCING
AS OF THE EFFECTIVE DATE AND CONTINUING IN EFFECT THROUGH DECEMBER 31, 2007;
PROVIDED, HOWEVER, THAT COMMENCING ON JANUARY 1, 2008 AND EACH JANUARY 1
THEREAFTER, THE TERM SHALL BE AUTOMATICALLY EXTENDED FOR ONE ADDITIONAL YEAR
UNLESS, NOT LATER THAN 90 DAYS PRIOR TO THE SCHEDULED EXPIRATION OF THE TERM (OR
ANY EXTENSION THEREOF), THE COMPANY SHALL HAVE GIVEN THE EXECUTIVE WRITTEN
NOTICE THAT THE TERM WILL NOT BE EXTENDED, EXCEPT AS OTHERWISE PROVIDED PURSUANT
TO SECTION 1.2.

3.             EMPLOYMENT STATUS; TERMINATION FOLLOWING CHANGE IN CONTROL.

3.1           NOT AN EMPLOYMENT CONTRACT.  THE EXECUTIVE ACKNOWLEDGES THAT THIS
AGREEMENT DOES NOT CONSTITUTE A CONTRACT OF EMPLOYMENT OR IMPOSE ON THE COMPANY
ANY OBLIGATION TO RETAIN THE EXECUTIVE AS AN EMPLOYEE AND THAT THIS AGREEMENT
DOES NOT PREVENT THE EXECUTIVE FROM TERMINATING EMPLOYMENT AT ANY TIME.  IF THE
EXECUTIVE’S EMPLOYMENT WITH THE COMPANY TERMINATES FOR ANY REASON AND
SUBSEQUENTLY A CHANGE IN CONTROL SHALL OCCUR, THE EXECUTIVE SHALL NOT BE
ENTITLED TO ANY BENEFITS HEREUNDER.

3.2           TERMINATION OF EMPLOYMENT.

(A)           IF THE CHANGE IN CONTROL DATE OCCURS DURING THE TERM, ANY
TERMINATION OF THE EXECUTIVE’S EMPLOYMENT BY THE COMPANY OR BY THE EXECUTIVE
WITHIN 12 MONTHS FOLLOWING THE CHANGE IN CONTROL DATE (OTHER THAN DUE TO THE
DEATH OF THE EXECUTIVE) SHALL BE COMMUNICATED BY A WRITTEN NOTICE TO THE OTHER
PARTY HERETO (THE “NOTICE OF TERMINATION”), GIVEN IN ACCORDANCE WITH SECTION 7. 
ANY NOTICE OF TERMINATION SHALL: (I) INDICATE THE SPECIFIC TERMINATION PROVISION
(IF ANY) OF THIS AGREEMENT RELIED UPON BY THE PARTY GIVING SUCH NOTICE, (II) TO
THE EXTENT APPLICABLE, SET FORTH IN REASONABLE DETAIL THE FACTS AND
CIRCUMSTANCES CLAIMED TO PROVIDE A BASIS FOR TERMINATION OF THE EXECUTIVE’S
EMPLOYMENT UNDER THE PROVISION SO INDICATED AND (III) SPECIFY THE DATE OF
TERMINATION (AS DEFINED BELOW).  THE EFFECTIVE DATE OF AN EMPLOYMENT TERMINATION
(THE “DATE OF TERMINATION”) SHALL BE THE CLOSE OF BUSINESS ON THE DATE SPECIFIED
IN THE NOTICE OF TERMINATION (WHICH DATE MAY NOT BE LESS THAN 15 DAYS OR MORE
THAN 120 DAYS AFTER THE DATE OF DELIVERY OF SUCH NOTICE OF TERMINATION), IN THE
CASE OF A TERMINATION OTHER THAN ONE DUE TO THE EXECUTIVE’S DEATH, OR THE DATE
OF THE EXECUTIVE’S DEATH, AS THE CASE MAY BE.  IN THE EVENT THE COMPANY FAILS TO
SATISFY THE REQUIREMENTS OF SECTION 3.2(A) REGARDING A NOTICE OF TERMINATION,
THE PURPORTED TERMINATION OF THE EXECUTIVE’S EMPLOYMENT PURSUANT TO SUCH NOTICE
OF TERMINATION SHALL NOT BE EFFECTIVE FOR PURPOSES OF THIS AGREEMENT.

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(B)           THE FAILURE BY THE EXECUTIVE OR THE COMPANY TO SET FORTH IN THE
NOTICE OF TERMINATION ANY FACT OR CIRCUMSTANCE WHICH CONTRIBUTES TO A SHOWING OF
GOOD REASON OR CAUSE SHALL NOT WAIVE ANY RIGHT OF THE EXECUTIVE OR THE COMPANY,
RESPECTIVELY, HEREUNDER OR PRECLUDE THE EXECUTIVE OR THE COMPANY, RESPECTIVELY,
FROM ASSERTING ANY SUCH FACT OR CIRCUMSTANCE IN ENFORCING THE EXECUTIVE’S OR THE
COMPANY’S RIGHTS HEREUNDER.

4.             BENEFITS TO EXECUTIVE.

4.1           STOCK ACCELERATION.  IF THE CHANGE IN CONTROL DATE OCCURS DURING
THE TERM AND THE EXECUTIVE’S EMPLOYMENT WITH THE COMPANY IS TERMINATED BY THE
COMPANY (OTHER THAN FOR CAUSE, DISABILITY OR DEATH) OR BY THE EXECUTIVE FOR GOOD
REASON WITHIN 12 MONTHS FOLLOWING THE CHANGE IN CONTROL, THEN, EFFECTIVE UPON
THE DATE OF TERMINATION, EACH OUTSTANDING AWARD THEN HELD BY THE EXECUTIVE UNDER
THE COMPANY’S OUTSTANDING EQUITY INCENTIVE PLANS SHALL BECOME IMMEDIATELY
EXERCISABLE IN FULL, SHALL BECOME IMMEDIATELY REALIZABLE OR DELIVERABLE, OR
RESTRICTIONS APPLICABLE TO EACH SUCH AWARD SHALL LAPSE IMMEDIATELY, AS
APPLICABLE.

4.2           COMPENSATION.  IF THE CHANGE IN CONTROL DATE OCCURS DURING THE
TERM AND THE EXECUTIVE’S EMPLOYMENT WITH THE COMPANY TERMINATES WITHIN 12 MONTHS
FOLLOWING THE CHANGE IN CONTROL DATE, THE EXECUTIVE SHALL BE ENTITLED TO THE
FOLLOWING BENEFITS:

(A)           TERMINATION WITHOUT CAUSE OR FOR GOOD REASON.  IF THE EXECUTIVE’S
EMPLOYMENT WITH THE COMPANY IS TERMINATED BY THE COMPANY (OTHER THAN FOR CAUSE,
DISABILITY OR DEATH) OR BY THE EXECUTIVE FOR GOOD REASON WITHIN 12 MONTHS
FOLLOWING THE CHANGE IN CONTROL DATE, THEN THE EXECUTIVE SHALL BE ENTITLED TO
THE FOLLOWING BENEFITS:

(I)            THE COMPANY SHALL PAY TO THE EXECUTIVE IN A LUMP SUM IN CASH
WITHIN 30 DAYS AFTER THE DATE OF TERMINATION THE AGGREGATE OF THE FOLLOWING
AMOUNTS:

(1)           THE SUM OF (A) THE EXECUTIVE’S BASE SALARY THROUGH THE DATE OF
TERMINATION AND (B) ANY ACCRUED VACATION PAY TO THE EXTENT NOT PREVIOUSLY PAID
(THE SUM OF THE AMOUNTS DESCRIBED IN CLAUSES (A) AND (B) SHALL BE HEREINAFTER
REFERRED TO AS THE “ACCRUED OBLIGATIONS”); AND

(2)           THE SUM OF (A) THE AMOUNT EQUAL TO THE EXECUTIVE’S ANNUAL BASE
SALARY DURING THE ONE YEAR PERIOD PRIOR TO THE DATE OF TERMINATION AND (B) THE
GREATER OF (X) THE TARGET BONUS ESTABLISHED BY THE BOARD (OR ANY OTHER PERSON OR
PERSONS HAVING AUTHORITY WITH RESPECT THERETO) FOR THE EXECUTIVE FOR THE FISCAL
YEAR IN WHICH THE DATE OF TERMINATION OCCURS AND (Y) THE ANNUAL BONUS PAID TO
THE EXECUTIVE FOR THE MOST RECENTLY COMPLETED FISCAL YEAR.

(II)           FOR 12 MONTHS AFTER THE DATE OF TERMINATION, OR SUCH LONGER
PERIOD AS MAY BE PROVIDED BY THE TERMS OF THE APPROPRIATE PLAN, PROGRAM,
PRACTICE OR POLICY, THE COMPANY SHALL CONTINUE TO PROVIDE BENEFITS TO THE
EXECUTIVE AND THE EXECUTIVE’S FAMILY AT LEAST EQUAL TO THOSE WHICH WOULD HAVE
BEEN PROVIDED TO THEM IF THE EXECUTIVE’S EMPLOYMENT HAD NOT BEEN TERMINATED, IN
ACCORDANCE WITH THE APPLICABLE LIFE INSURANCE, MEDICAL, DENTAL, HEALTH AND
ACCIDENT AND DISABILITY PLANS IN EFFECT IMMEDIATELY PRIOR TO THE DATE OF
TERMINATION OR, IF MORE FAVORABLE TO THE EXECUTIVE AND [HIS/HER] FAMILY, IN
EFFECT GENERALLY AT ANY TIME THEREAFTER WITH RESPECT TO OTHER PEER EXECUTIVES OF
THE COMPANY AND ITS AFFILIATED COMPANIES; PROVIDED, HOWEVER, THAT IF THE
EXECUTIVE BECOMES REEMPLOYED WITH ANOTHER EMPLOYER AND IS ELIGIBLE TO RECEIVE A
PARTICULAR TYPE OF BENEFITS (E.G., HEALTH INSURANCE BENEFITS) FROM SUCH EMPLOYER
ON TERMS AT LEAST AS FAVORABLE TO THE EXECUTIVE AND [HIS/HER] FAMILY AS THOSE
BEING PROVIDED BY THE COMPANY, THEN THE COMPANY SHALL NO LONGER BE REQUIRED TO
PROVIDE THOSE PARTICULAR BENEFITS TO THE EXECUTIVE AND [HIS/HER] FAMILY.  AT THE
END OF SUCH 12 MONTH PERIOD, THE EXECUTIVE MAY CONTINUE SUCH PLANS ON [HIS/HER]
OWN BEHALF OR PURSUANT TO COBRA, IF APPLICABLE, AND SHALL BE RESPONSIBLE FOR ALL
PREMIUMS THEREAFTER;

(III)          TO THE EXTENT NOT PREVIOUSLY PAID OR PROVIDED, THE COMPANY SHALL
TIMELY PAY OR PROVIDE TO THE EXECUTIVE ANY OTHER AMOUNTS OR BENEFITS REQUIRED TO
BE PAID OR PROVIDED OR WHICH THE EXECUTIVE IS ELIGIBLE TO RECEIVE FOLLOWING THE
EXECUTIVE’S TERMINATION OF EMPLOYMENT UNDER ANY PLAN, PROGRAM, POLICY, PRACTICE,
CONTRACT OR AGREEMENT OF THE COMPANY AND ITS AFFILIATED COMPANIES (SUCH OTHER
AMOUNTS AND BENEFITS SHALL BE HEREINAFTER REFERRED TO AS THE “OTHER BENEFITS”);
AND

(IV)          FOR PURPOSES OF DETERMINING ELIGIBILITY (BUT NOT THE TIME OF
COMMENCEMENT OF BENEFITS) OF THE EXECUTIVE FOR RETIREE BENEFITS TO WHICH THE
EXECUTIVE IS ENTITLED, THE EXECUTIVE SHALL BE CONSIDERED TO HAVE REMAINED
EMPLOYED BY THE COMPANY UNTIL 12 MONTHS AFTER THE DATE OF TERMINATION.

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(B)           RESIGNATION WITHOUT GOOD REASON; TERMINATION FOR DEATH OR
DISABILITY.  IF THE EXECUTIVE VOLUNTARILY TERMINATES [HIS/HER] EMPLOYMENT WITH
THE COMPANY WITHIN 12 MONTHS FOLLOWING THE CHANGE IN CONTROL DATE, EXCLUDING A
TERMINATION FOR GOOD REASON, OR IF THE EXECUTIVE’S EMPLOYMENT WITH THE COMPANY
IS TERMINATED BY REASON OF THE EXECUTIVE’S DEATH OR DISABILITY WITHIN 12 MONTHS
FOLLOWING THE CHANGE IN CONTROL DATE, THEN THE COMPANY SHALL (I) PAY THE
EXECUTIVE (OR [HIS/HER] ESTATE, IF APPLICABLE), IN A LUMP SUM IN CASH WITHIN 30
DAYS AFTER THE DATE OF TERMINATION, THE ACCRUED OBLIGATIONS AND (II) TIMELY PAY
OR PROVIDE TO THE EXECUTIVE THE OTHER BENEFITS.

(C)           TERMINATION FOR CAUSE.  IF THE COMPANY TERMINATES THE EXECUTIVE’S
EMPLOYMENT WITH THE COMPANY FOR CAUSE WITHIN 12 MONTHS FOLLOWING THE CHANGE IN
CONTROL DATE, THEN THE COMPANY SHALL (I) PAY THE EXECUTIVE, IN A LUMP SUM IN
CASH WITHIN 30 DAYS AFTER THE DATE OF TERMINATION, THE ACCRUED OBLIGATIONS AND
(II) TIMELY PAY OR PROVIDE TO THE EXECUTIVE THE OTHER BENEFITS.

4.3           TAXES.

(a)           Notwithstanding any other provision of this Agreement, except as
set forth in Section 4.3(b), in the event that the Company undergoes a  “Change
in Ownership or Control” (as defined below), the Company shall not be obligated
to provide to the Executive a portion of any “Contingent Compensation Payments”
(as defined below) that the Executive would otherwise be entitled to receive to
the extent necessary to eliminate any “excess parachute payments” (as defined in
Section 280G(b)(1) of the Internal Revenue Code of 1986, as amended (the
“Code”)) for the Executive.  For purposes of this Section 4.3, the Contingent
Compensation Payments so eliminated shall be referred to as the “Eliminated
Payments” and the aggregate amount (determined in accordance with Proposed
Treasury Regulation Section 1.280G-1, Q/A-30 or any successor provision) of the
Contingent Compensation Payments so eliminated shall be referred to as the
“Eliminated Amount.”

(b)           Notwithstanding the provisions of Section 4.3(a), no such
reduction in Contingent Compensation Payments shall be made if (i) the
Eliminated Amount (computed without regard to this sentence) exceeds (ii) 110%
of the aggregate present value (determined in accordance with Proposed Treasury
Regulation Section 1.280G-1, Q/A-31 and Q/A-32 or any successor provisions) of
the amount of any additional taxes that would be incurred by the Executive if
the Eliminated Payments (determined without regard to this sentence) were paid
to [him/her] (including, state and federal income taxes on the Eliminated
Payments, the excise tax imposed by Section 4999 of the Code payable with
respect to all of the Contingent Compensation Payments in excess of the
Executive’s “base amount” (as defined in Section 280G(b)(3) of the Code), and
any withholding taxes).  The override of such reduction in Contingent
Compensation Payments pursuant to this Section 4.3(b) shall be referred to as a
“Section 4.3(b) Override.”  For purpose of this paragraph, if any federal or
state income taxes would be attributable to the receipt of any Eliminated
Payment, the amount of such taxes shall be computed by multiplying the amount of
the Eliminated Payment by the maximum combined federal and state income tax rate
provided by law.

(c)           For purposes of this Section 4.3 the following terms shall have
the following respective meanings:

(i)            “Change in Ownership or Control” shall mean a change in the
ownership or effective control of the Company or in the ownership of a
substantial portion of the assets of the Company determined in accordance with
Section 280G(b)(2) of the Code.

(ii)         “Contingent Compensation Payment” shall mean any payment (or
benefit) in the nature of compensation that is made or made available (under
this Agreement or otherwise) to a “disqualified individual” (as defined in
Section 280G(c) of the Code) and that is contingent (within the meaning of
Section 280G(b)(2)(A)(i) of the Code) on a Change in Ownership or Control of the
Company.

(d)         Any payments or other benefits otherwise due to the Executive
following a Change in Ownership or Control that could reasonably be
characterized (as determined by the Company) as Contingent Compensation Payments
(the “Potential Payments”) shall not be made until the dates provided for in
this Section 4.3(d).  Within 30 days after each date on which the Executive
first becomes entitled to receive (whether or not then due) a Contingent
Compensation Payment relating to such Change in Ownership or Control, the
Company shall determine and notify the Executive (with reasonable detail
regarding the basis for its determinations) (i) which Potential Payments
constitute Contingent Compensation Payments, (ii) the Eliminated Amount and
(iii) whether the Section 4.3(b) Override is applicable.  Within 30 days after
delivery of such notice to the Executive, the Executive shall deliver a response
to the Company (the “Executive Response”) stating either (A) that [he/she]
agrees with the Company’s determination pursuant to the preceding sentence, in
which case

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[he/she] shall indicate, if applicable, which Contingent Compensation Payments,
or portions thereof (the aggregate amount of which, determined in accordance
with Proposed Treasury Regulation Section 1.280G-1, Q/A-30 or any successor
provision, shall be equal to the Eliminated Amount), shall be treated as
Eliminated Payments or (B) that [he/she] disagrees with such determination, in
which case [he/she] shall set forth (i) which Potential Payments should be
characterized as Contingent Compensation Payments, (ii) the Eliminated Amount,
(iii) whether the Section 4.3(b) Override is applicable, and (iv) which (if any)
Contingent Compensation Payments, or portions thereof (the aggregate amount of
which, determined in accordance with Proposed Treasury Regulation Section
1.280G-1, Q/A-30 or any successor provision, shall be equal to the Eliminated
Amount, if any), shall be treated as Eliminated Payments.  In the event that the
Executive fails to deliver an Executive Response on or before the required date,
the Company’s initial determination shall be final and the Contingent
Compensation Payments that shall be treated as Eliminated Payments shall be
determined by the Company in its absolute discretion.  If the Executive states
in the Executive Response that [he/she] agrees with the Company’s determination,
the Company shall make the Potential Payments to the Executive within three
business days following delivery to the Company of the Executive Response
(except for any Potential Payments which are not due to be made until after such
date, which Potential Payments shall be made on the date on which they are
due).  If the Executive states in the Executive Response that [he/she] disagrees
with the Company’s determination, then, for a period of 60 days following
delivery of the Executive Response, the Executive and the Company shall use good
faith efforts to resolve such dispute.  If such dispute is not resolved within
such 60-day period, such dispute shall be settled exclusively by arbitration in
Boston, Massachusetts, in accordance with the rules of the American Arbitration
Association then in effect.  Judgment may be entered on the arbitrator’s award
in any court having jurisdiction.  The Company shall, within three business days
following delivery to the Company of the Executive Response, make to the
Executive those Potential Payments as to which there is no dispute between the
Company and the Executive regarding whether they should be made (except for any
such Potential Payments which are not due to be made until after such date,
which Potential Payments shall be made on the date on which they are due).  The
balance of the Potential Payments shall be made within three business days
following the resolution of such dispute.  Subject to the limitations contained
in Sections 4.3(a) and (b) hereof, the amount of any payments to be made to the
Executive following the resolution of such dispute shall be increased by amount
of the accrued interest thereon computed at the prime rate announced from time
to time by The Wall Street Journal, compounded monthly from the date that such
payments originally were due.

(e)           The provisions of this Section 4.3 are intended to apply to any
and all payments or benefits available to the Executive under this Agreement or
any other agreement or plan of the Company under which the Executive receives
Contingent Compensation Payments.

4.4           MITIGATION.  THE EXECUTIVE SHALL NOT BE REQUIRED TO MITIGATE THE
AMOUNT OF ANY PAYMENT OR BENEFITS PROVIDED FOR IN THIS SECTION 4 BY SEEKING
OTHER EMPLOYMENT OR OTHERWISE. FURTHER, EXCEPT AS PROVIDED IN SECTION
4.2(A)(II), THE AMOUNT OF ANY PAYMENT OR BENEFITS PROVIDED FOR IN THIS SECTION 4
SHALL NOT BE REDUCED BY ANY COMPENSATION EARNED BY THE EXECUTIVE AS A RESULT OF
EMPLOYMENT BY ANOTHER EMPLOYER, BY RETIREMENT BENEFITS, BY OFFSET AGAINST ANY
AMOUNT CLAIMED TO BE OWED BY THE EXECUTIVE TO THE COMPANY OR OTHERWISE.

5.             DISPUTES.

5.1           SETTLEMENT OF DISPUTES; ARBITRATION.  ALL CLAIMS BY THE EXECUTIVE
FOR BENEFITS UNDER THIS AGREEMENT SHALL BE DIRECTED TO AND DETERMINED BY THE
BOARD OF DIRECTORS OF THE COMPANY AND SHALL BE IN WRITING.  ANY DENIAL BY THE
BOARD OF DIRECTORS OF A CLAIM FOR BENEFITS UNDER THIS AGREEMENT SHALL BE
DELIVERED TO THE EXECUTIVE IN WRITING AND SHALL SET FORTH THE SPECIFIC REASONS
FOR THE DENIAL AND THE SPECIFIC PROVISIONS OF THIS AGREEMENT RELIED UPON.  THE
BOARD OF DIRECTORS SHALL AFFORD A REASONABLE OPPORTUNITY TO THE EXECUTIVE FOR A
REVIEW OF THE DECISION DENYING A CLAIM.  ANY FURTHER DISPUTE OR CONTROVERSY
ARISING UNDER OR IN CONNECTION WITH THIS AGREEMENT SHALL BE SETTLED EXCLUSIVELY
BY ARBITRATION IN BOSTON, MASSACHUSETTS, IN ACCORDANCE WITH THE RULES OF THE
AMERICAN ARBITRATION ASSOCIATION THEN IN EFFECT.  JUDGMENT MAY BE ENTERED ON THE
ARBITRATOR’S AWARD IN ANY COURT HAVING JURISDICTION.

5.2           EXPENSES.  THE COMPANY AGREES TO PAY AS INCURRED, TO THE FULL
EXTENT PERMITTED BY LAW, ALL LEGAL, ACCOUNTING AND OTHER FEES AND EXPENSES WHICH
THE EXECUTIVE MAY REASONABLY INCUR AS A RESULT OF ANY CLAIM OR CONTEST
(REGARDLESS OF THE OUTCOME THEREOF) BY THE COMPANY, THE EXECUTIVE OR OTHERS
REGARDING THE VALIDITY OR ENFORCEABILITY OF, OR LIABILITY UNDER, ANY PROVISION
OF THIS AGREEMENT OR ANY GUARANTEE OF PERFORMANCE THEREOF (INCLUDING AS A RESULT
OF ANY CONTEST BY THE EXECUTIVE REGARDING THE AMOUNT OF ANY PAYMENT OR BENEFITS
PURSUANT TO THIS AGREEMENT), PLUS IN EACH CASE INTEREST ON ANY DELAYED PAYMENT
AT THE APPLICABLE FEDERAL RATE PROVIDED FOR IN SECTION 7872(F)(2)(A) OF THE
CODE.

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6.             SUCCESSORS.

6.1           SUCCESSOR TO COMPANY.  THE COMPANY SHALL REQUIRE ANY SUCCESSOR
(WHETHER DIRECT OR INDIRECT, BY PURCHASE, MERGER, CONSOLIDATION OR OTHERWISE) TO
ALL OR SUBSTANTIALLY ALL OF THE BUSINESS OR ASSETS OF THE COMPANY EXPRESSLY TO
ASSUME AND AGREE TO PERFORM THIS AGREEMENT TO THE SAME EXTENT THAT THE COMPANY
WOULD BE REQUIRED TO PERFORM IT IF NO SUCH SUCCESSION HAD TAKEN PLACE.  FAILURE
OF THE COMPANY TO OBTAIN AN ASSUMPTION OF THIS AGREEMENT AT OR PRIOR TO THE
EFFECTIVENESS OF ANY SUCCESSION SHALL BE A BREACH OF THIS AGREEMENT AND SHALL
CONSTITUTE GOOD REASON IF THE EXECUTIVE ELECTS TO TERMINATE EMPLOYMENT, EXCEPT
THAT FOR PURPOSES OF IMPLEMENTING THE FOREGOING, THE DATE ON WHICH ANY SUCH
SUCCESSION BECOMES EFFECTIVE SHALL BE DEEMED THE DATE OF TERMINATION.  AS USED
IN THIS AGREEMENT, “COMPANY” SHALL MEAN THE COMPANY AS DEFINED ABOVE AND ANY
SUCCESSOR TO ITS BUSINESS OR ASSETS AS AFORESAID WHICH ASSUMES AND AGREES TO
PERFORM THIS AGREEMENT, BY OPERATION OF LAW OR OTHERWISE.

6.2           SUCCESSOR TO EXECUTIVE.  THIS AGREEMENT SHALL INURE TO THE BENEFIT
OF AND BE ENFORCEABLE BY THE EXECUTIVE’S PERSONAL OR LEGAL REPRESENTATIVES,
EXECUTORS, ADMINISTRATORS, SUCCESSORS, HEIRS, DISTRIBUTEES, DEVISEES AND
LEGATEES.  IF THE EXECUTIVE SHOULD DIE WHILE ANY AMOUNT WOULD STILL BE PAYABLE
TO THE EXECUTIVE OR [HIS/HER] FAMILY HEREUNDER IF THE EXECUTIVE HAD CONTINUED TO
LIVE, ALL SUCH AMOUNTS, UNLESS OTHERWISE PROVIDED HEREIN, SHALL BE PAID IN
ACCORDANCE WITH THE TERMS OF THIS AGREEMENT TO THE EXECUTORS, PERSONAL
REPRESENTATIVES OR ADMINISTRATORS OF THE EXECUTIVE’S ESTATE.

7.             NOTICE.  ALL NOTICES, INSTRUCTIONS AND OTHER COMMUNICATIONS GIVEN
HEREUNDER OR IN CONNECTION HEREWITH SHALL BE IN WRITING.  ANY SUCH NOTICE,
INSTRUCTION OR COMMUNICATION SHALL BE SENT EITHER (I) BY REGISTERED OR CERTIFIED
MAIL, RETURN RECEIPT REQUESTED, POSTAGE PREPAID, OR (II) PREPAID VIA A REPUTABLE
NATIONWIDE OVERNIGHT COURIER SERVICE, IN EACH CASE ADDRESSED TO THE COMPANY, AT
675 WEST KENDALL STREET, CAMBRIDGE, MASSACHUSETTS 02142, AND TO THE EXECUTIVE AT
THE EXECUTIVE’S ADDRESS INDICATED ON THE SIGNATURE PAGE OF THIS AGREEMENT (OR TO
SUCH OTHER ADDRESS AS EITHER THE COMPANY OR THE EXECUTIVE MAY HAVE FURNISHED TO
THE OTHER IN WRITING IN ACCORDANCE HEREWITH).  ANY SUCH NOTICE, INSTRUCTION OR
COMMUNICATION SHALL BE DEEMED TO HAVE BEEN DELIVERED FIVE BUSINESS DAYS AFTER IT
IS SENT BY REGISTERED OR CERTIFIED MAIL, RETURN RECEIPT REQUESTED, POSTAGE
PREPAID, OR ONE BUSINESS DAY AFTER IT IS SENT VIA A REPUTABLE NATIONWIDE
OVERNIGHT COURIER SERVICE. EITHER PARTY MAY GIVE ANY NOTICE, INSTRUCTION OR
OTHER COMMUNICATION HEREUNDER USING ANY OTHER MEANS, BUT NO SUCH NOTICE,
INSTRUCTION OR OTHER COMMUNICATION SHALL BE DEEMED TO HAVE BEEN DULY DELIVERED
UNLESS AND UNTIL IT ACTUALLY IS RECEIVED BY THE PARTY FOR WHOM IT IS INTENDED.

8.             MISCELLANEOUS.

8.1           EMPLOYMENT BY SUBSIDIARY.  FOR PURPOSES OF THIS AGREEMENT, THE
EXECUTIVE’S EMPLOYMENT WITH THE COMPANY SHALL NOT BE DEEMED TO HAVE TERMINATED
SOLELY AS A RESULT OF THE EXECUTIVE CONTINUING TO BE EMPLOYED BY A WHOLLY-OWNED
SUBSIDIARY OF THE COMPANY.

8.2           SEVERABILITY.  THE INVALIDITY OR UNENFORCEABILITY OF ANY PROVISION
OF THIS AGREEMENT SHALL NOT AFFECT THE VALIDITY OR ENFORCEABILITY OF ANY OTHER
PROVISION OF THIS AGREEMENT, WHICH SHALL REMAIN IN FULL FORCE AND EFFECT.

8.3           INJUNCTIVE RELIEF.  THE COMPANY AND THE EXECUTIVE AGREE THAT ANY
BREACH OF THIS AGREEMENT BY THE COMPANY IS LIKELY TO CAUSE THE EXECUTIVE
SUBSTANTIAL AND IRREVOCABLE DAMAGE AND THEREFORE, IN THE EVENT OF ANY SUCH
BREACH, IN ADDITION TO SUCH OTHER REMEDIES WHICH MAY BE AVAILABLE, THE EXECUTIVE
SHALL HAVE THE RIGHT TO SPECIFIC PERFORMANCE AND INJUNCTIVE RELIEF.

8.4           GOVERNING LAW.  THE VALIDITY, INTERPRETATION, CONSTRUCTION AND
PERFORMANCE OF THIS AGREEMENT SHALL BE GOVERNED BY THE INTERNAL LAWS OF THE
COMMONWEALTH OF MASSACHUSETTS, WITHOUT REGARD TO CONFLICTS OF LAW PRINCIPLES.

8.5           WAIVERS.  NO WAIVER BY THE EXECUTIVE AT ANY TIME OF ANY BREACH OF,
OR COMPLIANCE WITH, ANY PROVISION OF THIS AGREEMENT TO BE PERFORMED BY THE
COMPANY SHALL BE DEEMED A WAIVER OF THAT OR ANY OTHER PROVISION AT ANY
SUBSEQUENT TIME.

8.6           COUNTERPARTS.  THIS AGREEMENT MAY BE EXECUTED IN COUNTERPARTS,
EACH OF WHICH SHALL BE DEEMED TO BE AN ORIGINAL BUT BOTH OF WHICH TOGETHER SHALL
CONSTITUTE ONE AND THE SAME INSTRUMENT.

8.7           TAX WITHHOLDING.  ANY PAYMENTS PROVIDED FOR HEREUNDER SHALL BE
PAID NET OF ANY APPLICABLE TAX WITHHOLDING REQUIRED UNDER FEDERAL, STATE OR
LOCAL LAW.

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8.8           ENTIRE AGREEMENT.  THIS AGREEMENT SETS FORTH THE ENTIRE AGREEMENT
OF THE PARTIES HERETO IN RESPECT OF THE SUBJECT MATTER CONTAINED HEREIN AND
SUPERSEDES ALL PRIOR AGREEMENTS, PROMISES, COVENANTS, ARRANGEMENTS,
COMMUNICATIONS, REPRESENTATIONS OR WARRANTIES, WHETHER ORAL OR WRITTEN, BY ANY
OFFICER, EMPLOYEE OR REPRESENTATIVE OF ANY PARTY HERETO IN RESPECT OF THE
SUBJECT MATTER CONTAINED HEREIN; AND ANY PRIOR AGREEMENT OF THE PARTIES HERETO
IN RESPECT OF THE SUBJECT MATTER CONTAINED HEREIN IS HEREBY TERMINATED AND
CANCELLED.

8.9           SECTION 409A.  NO PAYMENTS THAT MAY BE MADE PURSUANT TO THIS
AGREEMENT THAT CONSTITUTE “NONQUALIFIED DEFERRED COMPENSATION” WITHIN THE
MEANING OF SECTION 409A OF THE INTERNAL REVENUE CODE AND THE GUIDANCE ISSUED
THEREUNDER (“SECTION 409A”) MAY BE ACCELERATED OR DEFERRED BY THE COMPANY OR THE
EXECUTIVE.  NOTWITHSTANDING ANYTHING ELSE TO THE CONTRARY IN THIS AGREEMENT, TO
THE EXTENT THAT ANY OF THE PAYMENTS TO BE MADE HEREUNDER CONSTITUTE
“NONQUALIFIED DEFERRED COMPENSATION” WITHIN THE MEANING OF SECTION 409A AND THE
EXECUTIVE IS A “SPECIFIED EMPLOYEE,” THEN UPON [HIS /HER] TERMINATION (AS
DEFINED UNDER SECTION 409A), ANY SUCH PAYMENT SHALL BE DELAYED UNTIL THE DATE
THAT IS SIX MONTHS AND ONE DAY FOLLOWING THE DATE OF TERMINATION IF, ABSENT SUCH
DELAY, SUCH PAYMENT WOULD OTHERWISE BE SUBJECT TO PENALTIES UNDER SECTION 409A. 
IN ANY EVENT, THE COMPANY MAKES NO REPRESENTATION OR WARRANTY AND SHALL HAVE NO
LIABILITY TO THE EXECUTIVE OR ANY OTHER PERSON IF ANY PROVISIONS OF THIS
AGREEMENT ARE DETERMINED TO CONSTITUTE DEFERRED COMPENSATION SUBJECT TO SECTION
409A BUT DO NOT SATISFY THE CONDITIONS OF SUCH SECTION.

8.10         AMENDMENTS.  THIS AGREEMENT MAY BE AMENDED OR MODIFIED ONLY BY A
WRITTEN INSTRUMENT EXECUTED BY BOTH THE COMPANY AND THE EXECUTIVE.

8.11         EXECUTIVE’S ACKNOWLEDGEMENTS.  THE EXECUTIVE ACKNOWLEDGES THAT
[HE/SHE]: (A) HAS READ THIS AGREEMENT; (B) HAS BEEN REPRESENTED IN THE
PREPARATION, NEGOTIATION, AND EXECUTION OF THIS AGREEMENT BY LEGAL COUNSEL OF
THE EXECUTIVE’S OWN CHOICE OR HAS VOLUNTARILY DECLINED TO SEEK SUCH COUNSEL; (C)
UNDERSTANDS THE TERMS AND CONSEQUENCES OF THIS AGREEMENT; AND (D) UNDERSTANDS
THAT THE LAW FIRM OF WILMERHALE IS ACTING AS COUNSEL TO THE COMPANY IN
CONNECTION WITH THE TRANSACTIONS CONTEMPLATED BY THIS AGREEMENT, AND IS NOT
ACTING AS COUNSEL FOR THE EXECUTIVE.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
day and year first set forth above.

MOMENTA PHARMACEUTICALS, INC.

 

 

 

By:

 

 

 

 

 

 

 

Title:

 

 

 

 

 

 

 

Date:

 

 

 

 

 

 

 

[NAME OF EXECUTIVE]

 

 

 

 

 

 

 

 

 

Signature:

 

 

 

 

 

Address:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Date:

 

 

 

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