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Exhibit 10.18    
    


INDEMNIFICATION AGREEMENT  


        This Agreement, made and entered into this    day
of                        ("Agreement"), by and between Sirtris Pharmaceuticals, Inc., a Delaware
corporation (the "Company"), and [                        ] (the ["Officer] ["Director"]; collectively with such
[Officer's] [Director's] Affiliated Persons (as defined in Section 19(a) hereof), "Indemnitee" or "Indemnitees"): 


        WHEREAS,
it is reasonable, prudent and necessary for the Company to obligate itself to indemnify, and to advance expenses on behalf of, its directors and executive officers to the
fullest extent permitted by applicable law so that they will serve or continue to serve the Company free from undue concern that they will not be so indemnified; and 



        WHEREAS,
Indemnitee is willing to serve, continue to serve the Company as a director and/or executive officer and to take on additional service for or on its behalf on the condition that
he be so indemnified; 


        NOW,
THEREFORE, in consideration of the premises and the covenants contained herein, the Company and Indemnitee do hereby covenant and agree as follows: 


	1.
	Services by Indemnitee. Indemnitee agrees to serve as a director and/or executive officer of the Company. Indemnitee may at any time and
for any reason resign from such position (subject to any other contractual obligation or any obligation imposed by operation of law).



	2.
	Indemnification—General. The Company shall indemnify, and advance Expenses (as hereinafter defined) to, Indemnitee
(a) as provided in this Agreement and (b) (subject to the provisions of this Agreement) to the fullest extent permitted by applicable law in effect on the date hereof and as amended from
time to time. The rights of Indemnitee provided under the preceding sentence shall include, but shall not be limited to, the rights set forth in the other Sections of this Agreement.



	3.
	Proceedings Other Than Proceedings by or in the Right of the Company. Indemnitee shall be entitled to the rights of indemnification
provided in this Section 3 if, by reason of Indemnitee's Corporate Status (as hereinafter defined), Indemnitee is, or is threatened to be made, a party to or a participant in any threatened,
pending or completed Proceeding (as hereinafter defined), other than a Proceeding by or in the right of the Company. Pursuant to this Section 3, Indemnitee shall be indemnified against all
Expenses, judgments, penalties, fines and amounts paid in settlement (including all interest, assessments and other charges paid or payable in connection with or in respect of such Expenses,
judgments, penalties, fines and amounts paid in settlement) actually and reasonably incurred by Indemnitee or on behalf of Indemnitee in connection with such Proceeding or any claim, issue or matter
therein, if Indemnitee acted in good faith and in a manner Indemnitee reasonably believed to be in or not opposed to the best interests of the Company and, with respect to any criminal Proceeding, had
no reasonable cause to believe Indemnitee's conduct was unlawful.



	4.
	Proceedings by or in the Right of the Company. Indemnitee shall be entitled to the rights of indemnification provided in this
Section 4 if, by reason of Indemnitee's Corporate Status, Indemnitee is, or is threatened to be made, a party to or a participant in any threatened, pending or completed Proceeding brought by
or in the right of the Company to procure a judgment in its favor. Pursuant to this Section, Indemnitee shall be indemnified against all Expenses (including all interest, assessments and other charges
paid or payable in connection with or in respect of such Expenses) actually and reasonably incurred by Indemnitee or on behalf of Indemnitee in connection with such Proceeding if Indemnitee acted in
good faith and in a manner Indemnitee reasonably believed to be in or not opposed to the best interests of the Company; provided,  however, that
indemnification against such Expenses shall be made in respect of any claim, issue or matter in such Proceeding as to which Indemnitee
shall have been adjudged to be liable to the Company if and only to the extent that the Court of Chancery of the State of Delaware, or the 







 

court
in which such Proceeding shall have been brought or is pending, shall determine that such indemnification may be made. 



	5.
	Partial Indemnification. Notwithstanding any other provision of this Agreement, to the extent that Indemnitee is, by reason of
Indemnitee's Corporate Status, a party to (or a participant in) and is successful, on the merits or otherwise, in defense of any Proceeding, Indemnitee shall be indemnified against all Expenses
actually and reasonably incurred by Indemnitee or on behalf of Indemnitee in connection therewith. If Indemnitee is not wholly successful in defense of such Proceeding but is successful, on the merits
or otherwise, as to one or more but less than all claims, issues or matters in such Proceeding, the Company shall indemnify Indemnitee against all Expenses actually and reasonably incurred by
Indemnitee or on behalf of Indemnitee in connection with each successfully resolved claim, issue or matter. For purposes of this Section and without limitation, the termination of any claim, issue or
matter in such a Proceeding by dismissal, with or without prejudice, shall be deemed to be a successful result as to such claim, issue or matter. If Indemnitee is entitled under any provision of this
agreement to indemnification by the Company for some or a portion of the Expenses, judgments, penalties, fines and amounts paid in settlement (including all interest, assessments and other charges
paid or payable in connection with or in respect of such Expenses, judgments, penalties, fines and amounts paid in settlement) actually and reasonably incurred by Indemnitee or on behalf of Indemnitee
in connection with such Proceeding or any claim, issue or matter therein, but not, however, for the total amount thereof, the Company shall nevertheless indemnify Indemnitee for the portion to which
Indemnitee is entitled.



	6.
	Indemnification for Additional Expenses.



	a.
	The
Company shall indemnify Indemnitee against any and all Expenses and, if requested by Indemnitee, shall (within five (5) business days of such request) advance such Expenses
to Indemnitee, which are incurred by Indemnitee in connection with any action brought by Indemnitee for (i) indemnification or advance payment of Expenses by the Company under this Agreement or
any other agreement or by-law of the Company now or hereafter in effect; or (ii) recovery under any directors' and officers' liability insurance policies maintained by the Company,
regardless of whether Indemnitee ultimately is determined to be entitled to such indemnification, advance expense payment or insurance recovery, as the case may be.



	b.
	Notwithstanding
any other provision of this Agreement, to the extent that Indemnitee is, by reason of Indemnitee's Corporate Status, a witness in any Proceeding to which Indemnitee is
not a party, Indemnitee shall be indemnified against all Expenses actually and reasonably incurred by Indemnitee or on behalf of Indemnitee in connection therewith.






	7.
	Advancement of Expenses. The Company shall advance all reasonable Expenses incurred by or on behalf of Indemnitee in connection with any
Proceeding within five (5) days after the receipt by the Company of a statement or statements from Indemnitee requesting such advance or advances from time to time, whether prior to or after
final disposition of such Proceeding. Such statement or statements shall reasonably evidence the Expenses incurred by Indemnitee and shall include or be preceded or accompanied by an undertaking by or
on behalf of Indemnitee to repay any Expenses advanced if it shall ultimately be determined that Indemnitee is not entitled to be indemnified against such Expenses. Notwithstanding the foregoing, the
obligation of the Company to advance Expenses pursuant to this Section 7 shall be subject to the condition that, if, when and to the extent that the Company determines that Indemnitee would not
be permitted to be indemnified under applicable law, the Company shall be entitled to be reimbursed, within thirty (30) days of such determination, by Indemnitee (who hereby agrees to reimburse
the Company) for all such amounts theretofore paid; provided, however, that if Indemnitee has commenced
or thereafter commences legal proceedings in a court of competent jurisdiction to secure a determination that Indemnitee should be indemnified under applicable law, any determination 


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made
by the Company that Indemnitee would not be permitted to be indemnified under applicable law shall not be binding and Indemnitee shall not be required to reimburse the Company for any advance of
Expenses until a final judicial determination is made with respect thereto (as to which all rights of appeal therefrom have been exhausted or lapsed). 



	8.
	Procedure for Determination of Entitlement to Indemnification.



	a.
	To
obtain indemnification under this Agreement, Indemnitee shall submit to the Company a written request, including therein or therewith such documentation and information as is
reasonably available to Indemnitee and is reasonably necessary to determine whether and to what extent Indemnitee is entitled to indemnification. The Secretary of the Company shall, promptly upon
receipt of such a request for indemnification, advise the Board in writing that Indemnitee has requested indemnification.



	b.
	Upon
written request by Indemnitee for indemnification pursuant to the first sentence of Section 8(a) hereof, a determination, if required by applicable law, with respect to
Indemnitee's entitlement thereto shall be made in the specific case: (i) if a Change in Control (as hereinafter defined) shall have occurred, by Independent Counsel (as hereinafter defined) in
a written opinion to the Board of Directors, a copy of which shall be delivered to Indemnitee; or (ii) if a Change of Control shall not have occurred, (A) by a majority vote of the
Disinterested Directors (as hereinafter defined), even though less than a quorum of the Board, or (B) if there are no such Disinterested Directors or, if such Disinterested Directors so direct,
by Independent Counsel in a written opinion to the Board, a copy of which shall be delivered to Indemnitee or (C) if so directed by the Board, by the stockholders of the Company; and, if it is
so determined that Indemnitee is entitled to indemnification, payment to Indemnitee shall be made within seven (7) days after such determination. The Company and Indemnitee shall each cooperate
with the person, persons or entity making such determination with respect to Indemnitee's entitlement to indemnification, including providing to such person, persons or entity upon reasonable advance
request any documentation or information which is not privileged or otherwise protected from disclosure and which is reasonably available to Indemnitee and reasonably necessary to such determination.
Any costs or expenses (including attorneys' fees and disbursements) incurred by Indemnitee in so cooperating with the person, persons or entity making such determination shall be borne by the Company
(irrespective of the determination as to Indemnitee's entitlement to indemnification), and the Company hereby indemnifies and agrees to hold Indemnitee harmless therefrom.



	c.
	In
the event the determination of entitlement to indemnification is to be made by Independent Counsel pursuant to Section 8(b) hereof, the Independent Counsel shall be selected
as provided in this Section 8(c). If a Change of Control shall not have occurred, the Independent Counsel shall be selected by the Board of Directors, and the Company shall give written notice
to Indemnitee advising him of the identity of the Independent Counsel so selected. If a Change of Control shall have occurred, the Independent Counsel shall be selected by Indemnitee (unless
Indemnitee shall request that such selection be made by the Board of Directors, in which event the preceding sentence shall apply), and Indemnitee shall give written notice to the Company advising it
of the identity of the Independent Counsel so selected. In either event, Indemnitee or the Company, as the case may be, may, within ten (10) days after such written notice of selection shall
have been given, deliver to the Company or to Indemnitee, as the case may be, a written objection to such selection; provided,  however, that such objection
may be asserted only on the ground that the Independent Counsel so selected does not meet the requirements of "Independent
Counsel" as defined in Section 19 of this Agreement, and the objection shall set forth with particularity the factual basis of such assertion. If such written objection is so made and
substantiated, the Independent Counsel so 





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selected
may not serve as Independent Counsel unless and until such objection is withdrawn or a court has determined that such objection is without merit. If, within twenty (20) days after
submission by Indemnitee of a written request for indemnification pursuant to Section 8(a) hereof, no Independent Counsel shall have been selected and not objected to, either the Company or
Indemnitee may petition the Court of Chancery of the State of Delaware for resolution of any objection which shall have been made by the Company or Indemnitee to the other's selection of Independent
Counsel and/or for the appointment as Independent Counsel of a person selected by the Court or by such other person as the Court shall designate, and the person with respect to whom all objections are
so resolved or the person so appointed shall act as Independent Counsel under Section 8(b) hereof. The Company shall pay any and all reasonable fees and expenses of Independent Counsel incurred
by such Independent Counsel in connection with acting pursuant to Section 8(b) hereof, and the Company shall pay all reasonable fees and expenses incident to the procedures of this
Section 8(c), regardless of the manner in which such Independent Counsel was selected or appointed, and if such Independent Counsel was selected or appointed by Indemnitee or the Court, shall
provide such Independent Counsel with such retainer as may requested by such counsel. Upon the due commencement of any judicial proceeding or arbitration pursuant to
Section 10(a)(iii) of this Agreement, Independent Counsel shall be discharged and relieved of any further responsibility in such capacity (subject to the applicable standards of
professional conduct then prevailing). 



	d.
	The
Company shall not be required to obtain the consent of Indemnitee to the settlement of any Proceeding which the Company has undertaken to defend if the Company assumes full and
sole responsibility for such settlement and the settlement grants Indemnitee a complete and unqualified release in respect of the potential liability. The Company shall not be liable for any amount
paid by Indemnitee in settlement of any Proceeding that is not defended by the Company, unless the Company has consented to such settlement, which consent shall not be unreasonably withheld.






	9.
	Presumptions and Effect of Certain Proceedings.



	a.
	In
making a determination with respect to entitlement to indemnification or the advancement of expenses hereunder, the person or persons or entity making such determination shall
presume that Indemnitee is entitled to indemnification or advancement of expenses under this Agreement if Indemnitee has submitted a request for indemnification or the advancement of expenses in
accordance with Section 8(a) of this Agreement, and the Company shall have the burden of proof to overcome that presumption in connection with the making by any person, persons or entity of any
determination contrary to that presumption. Neither the failure of the Company (including its board of directors or independent legal counsel) to have made a determination prior to the commencement of
any action pursuant to this Agreement that indemnification is proper in the circumstances because Indemnitee has met the applicable standard of conduct, nor an actual determination by the Company
(including its board of directors or independent legal counsel) that Indemnitee has not met such applicable standard of conduct, shall be a defense to the action or create a presumption that
Indemnitee has not met the applicable standard of conduct.



	b.
	If
the person, persons or entity empowered or selected under Section 8 of this Agreement to determine whether Indemnitee is entitled to indemnification shall not have made a
determination within sixty (60) days after receipt by the Company of the request therefor, the requisite determination of entitlement to indemnification shall be deemed to have been made and
Indemnitee shall be entitled to such indemnification, absent (i) a misstatement by Indemnitee of a material fact, or an omission of a material fact necessary to make Indemnitee's statement not
materially misleading, in connection with the request for 





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indemnification,
or (ii) a prohibition of such indemnification under applicable law; provided,  however, that such 60-day period may be extended for a reasonable time,
not to exceed an additional thirty (30) days, if the person,
persons or entity making the determination with respect to entitlement to indemnification in good faith requires such additional time for the obtaining or evaluating of documentation and/or
information relating thereto; and provided, further, that the foregoing provisions of this Section 9(b) shall not apply (i) if the determination of entitlement to indemnification is to
be made by the stockholders pursuant to Section 8(b) of this Agreement and if (A) within fifteen (15) days after receipt by the Company of the request for such determination the
Board of Directors has resolved to submit such determination to the stockholders for their consideration at an annual meeting thereof to be held within seventy-five (75) days after
such receipt and such determination is made thereat, or (B) a special meeting of stockholders is called within fifteen (15) days after such receipt for the purpose of making such
determination, such meeting is held for such purpose within sixty (60) days after having been so called and such determination is made thereat, or (ii) if the determination of
entitlement to indemnification is to be made by Independent Counsel pursuant to Section 8(b) of this Agreement. 



	c.
	The
termination of any Proceeding or of any claim, issue or matter therein, by judgment, order, settlement or conviction, or upon a plea of nolo
contendere or its equivalent, shall not (except as otherwise expressly provided in this Agreement) of itself adversely affect the right of Indemnitee to indemnification or
create a presumption that Indemnitee did not act in good faith and in a manner which he reasonably believed to be in or not opposed to the best interests of the Company or, with respect to any
criminal Proceeding, that Indemnitee had reasonable cause to believe that his conduct was unlawful.



	d.
	Reliance as Safe Harbor. For purposes of any determination of good faith, Indemnitee shall be deemed to have acted in good faith if
Indemnitee's action is based on the records or books of account of the Company or relevant enterprise, including financial statements, or on information supplied to Indemnitee by the officers of the
Company or relevant enterprise in the course of their duties, or on the advice of legal counsel for the Company or relevant enterprise or on information or records given in reports made to the Company
or relevant enterprise by an independent certified public accountant or by an appraiser or other expert selected with reasonable care by the Company or relevant enterprise. The provisions of this
Section 9(d) shall not be deemed to be exclusive or to limit in any way the other circumstances in which Indemnitee may be deemed to have met the applicable standard of conduct set forth in
this Agreement.



	e.
	Actions of Others. The knowledge and/or actions, or failure to act, of any director, officer, agent or employee of the Company or
relevant enterprise shall not be imputed to Indemnitee for purposes of determining the right to indemnification under this Agreement.






	10.
	Remedies of Indemnitee.



	a.
	In
the event that (i) a determination is made pursuant to Section 8 of this Agreement that Indemnitee is not entitled to indemnification under this Agreement,
(ii) advancement of Expenses is not timely made pursuant to Section 7 of this Agreement, (iii) no determination of entitlement to indemnification shall have been made pursuant to
Section 8(b) of this Agreement within ninety (90) days after receipt by the Company of the request for indemnification, (iv) payment of indemnification is not made pursuant to
Section 5 or 6 of this Agreement within ten (10) days after receipt by the Company of a written request therefor, or (v) payment of indemnification is not made within ten
(10) days after a determination has been made that Indemnitee is entitled to indemnification, Indemnitee shall be entitled to an adjudication by the Court of Chancery of the State of Delaware,
or any other court of competent jurisdiction, of his entitlement to such indemnification or advancement of Expenses. Alternatively, Indemnitee, at his option, may seek an award in arbitration to be
conducted by a single arbitrator pursuant to the Commercial Arbitration Rules of the American Arbitration Association. 





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	b.
	In
the event that a determination shall have been made pursuant to Section 8(b) of this Agreement that Indemnitee is not entitled to indemnification, any judicial proceeding or
arbitration commenced pursuant to this Section 10 shall be conducted in all respects as a de novo trial, or arbitration, on the merits and
Indemnitee shall not be prejudiced by reason of that adverse determination. If a Change of Control shall have occurred, in any judicial proceeding or arbitration commenced pursuant to this
Section 10, the Company shall have the burden of proving that Indemnitee is not entitled to indemnification or advancement of Expenses, as the case may be.



	c.
	If
a determination shall have been made pursuant to Section 8(b) of this Agreement that Indemnitee is entitled to indemnification, the Company shall be bound by such
determination in any judicial proceeding or arbitration commenced pursuant to this Section 10, absent (i) a misstatement by Indemnitee of a material fact, or an omission of a material
fact necessary to make Indemnitee's statement not materially misleading in connection with the request for indemnification, or (ii) a prohibition of such indemnification under applicable law.



	d.
	In
the event that Indemnitee, pursuant to this Section 10, seeks a judicial adjudication of or an award in arbitration to enforce his rights under, or to recover damages for
breach of, this Agreement, Indemnitee shall be entitled to recover from the Company, and shall be indemnified by the Company against, any and all expenses (of the types described in the definition of
Expenses in Section 19 of this Agreement) actually and reasonably incurred by him in such judicial adjudication or arbitration, but only if he prevails therein. If it shall be determined in
said judicial adjudication or arbitration that Indemnitee is entitled to receive part but not all of the indemnification or advancement of expenses sought, the expenses incurred by Indemnitee in
connection with such judicial adjudication or arbitration shall be appropriately prorated. The Company shall indemnify Indemnitee against any and all Expenses and, if requested by Indemnitee, shall
(within ten (10) days after receipt by the Company of a written request therefor) advance such expenses to Indemnitee, which are incurred by Indemnitee in connection with any action brought by
Indemnitee for indemnification or advance of Expenses from the Company under this Agreement or under any directors' or officers' liability insurance policies maintained by the Company, regardless of
whether Indemnitee ultimately is determined to be entitled to such indemnification, advancement of Expenses or insurance recovery, as the case may be.



	e.
	The
Company shall be precluded from asserting in any judicial proceeding or arbitration commenced pursuant to this Section 10 that the procedures and presumptions of this
Agreement are not valid, binding and enforceable and shall stipulate in any such court or before any such arbitrator that the Company is bound by all the provisions of this Agreement.






	11.
	Non-Exclusivity; Survival of Rights; Insurance; Subrogation.



	a.
	The
rights of indemnification and to receive advancement of Expenses as provided by this Agreement shall not be deemed exclusive of any other rights to which Indemnitee may at any time
be entitled under applicable law, the Certificate of Incorporation, the Bylaws, any agreement, a vote of stockholders or a resolution of directors, or otherwise. No amendment, alteration or repeal of
this Agreement or of any provision hereof shall limit or restrict any right of Indemnitee under this Agreement in respect of any action taken or omitted by such Indemnitee in Indemnitee's Corporate
Status prior to such amendment, alteration or repeal. To the extent that a change in the General Corporation Law of the State of Delaware, whether by statute or judicial decision, permits greater
indemnification or advancement of Expenses than would be afforded currently under the Company's Bylaws and this Agreement, it is the intent of the parties hereto that Indemnitee shall enjoy by this
Agreement the greater benefits so afforded by such change. No right or remedy herein conferred is intended to be 





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exclusive
of any other right or remedy, and every other right and remedy shall be cumulative and in addition to every other right and remedy given hereunder or now or hereafter existing at law or in
equity or otherwise. The assertion or employment of any right or remedy hereunder, or otherwise, shall not prevent the concurrent assertion or employment of any other right or remedy. 



	b.
	To
the extent that the Company maintains an insurance policy or policies providing liability insurance for directors, officers, employees or agents of the Company or of any other
corporation, partnership, joint venture, trust, employee benefit plan or other enterprise which such person serves at the request of the Company, Indemnitee shall be covered by such policy or policies
in accordance with its or their terms to the maximum extent of the coverage available for any such director, officer, employee or agent under such policy or policies.



	c.
	In
the event of any payment under this Agreement, the Company shall be subrogated to the extent of such payment to all of the rights of recovery of Indemnitee, who shall execute all
papers required and take all action necessary to secure such rights, including execution of such documents as are necessary to enable the Company to bring suit or enforce such rights.



	d.
	The
Company shall not be liable under this Agreement to make any payment of amounts otherwise indemnifiable hereunder if and to the extent that Indemnitee has otherwise actually
received such payment under any insurance policy, contract, agreement or otherwise.



	e.
	The
Company's obligation to indemnify or advance expenses hereunder to Indemnitee who is or was serving at the request of the Company as a director, officer, employee or agent of any
other corporation, partnership, joint venture, trust, employee benefit plan or other enterprise shall be reduced by any amount Indemnitee has actually received as indemnification or advancement of
expenses from such other corporation, partnership, joint venture, trust, employee benefit plan or other enterprise.






	12.
	Period of Limitations. No legal action shall be brought and no cause of action shall be asserted by or in the right of the Company
against any Indemnitee, such Indemnitee's estate, spouse, heirs, executors or personal or legal representatives after the expiration of two (2) years from the date of accrual of such cause of
action, and any claim or cause of action of the Company shall be extinguished and deemed released unless asserted by the timely filing of a legal action within such two (2)-year period;  provided,
however, that if any shorter period of limitations is otherwise applicable to any such cause
of action, such shorter period shall govern.



	13.
	Liability Insurance. To the extent the Company maintains liability insurance applicable to directors, officers, employees, control
persons, fiduciaries or other agents and affiliates, each Indemnitee shall be covered by such policies in such a manner as to provide to the Indemnitee the same rights and benefits as are accorded to
the most favorably insured of the Company's directors, if such Indemnitee is a director, or of the Company's officers, if such Indemnitee is not a director of the Company but is an officer.



	14.
	Duration of Agreement.



	a.
	This
Agreement shall continue until and terminate upon the later of: (i) ten (10) years after the date that Indemnitee shall have ceased to serve as a director and/or
executive officer of the Company (or of any other corporation, partnership, joint venture, trust, employee benefit plan or other enterprise which Indemnitee served at the request of the Company); or
(ii) the final termination of any Proceeding then pending in respect of which Indemnitee is granted rights of indemnification or advancement of expenses hereunder and of any proceeding
commenced by Indemnitee pursuant to Section 10 of this Agreement relating thereto. 





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	b.
	This
Agreement shall not be deemed an employment contract between the Company (or any of its subsidiaries) and Indemnitee. Indemnitee specifically acknowledges that Indemnitee's
employment with the Company (or any of its subsidiaries), if any, is at will, and Indemnitee may be discharged at any time for any reason, with or without cause, except as may be otherwise provided in
any written employment contract between Indemnitee and the Company (or any of its subsidiaries), other applicable formal severance policies duly adopted by the Board, or, with respect to service as a
director or officer of the Company, by the Company's Certificate of Incorporation, Bylaws, and the General Corporation Law of the State of Delaware. The foregoing notwithstanding, this Agreement shall
continue in force as provided above after Indemnitee has ceased to serve as a director and/or executive officer of the Company.



	c.
	This
Agreement shall be binding upon the Company and its successors and assigns and shall inure to the benefit of Indemnitee and his heirs, executors and administrators.






	15.
	Severability. If any provision or provisions of this Agreement shall be held to be invalid, illegal or unenforceable for any reason
whatsoever: (a) the validity, legality and enforceability of the remaining provisions of this Agreement (including without limitation, each portion of any Section of this Agreement containing
any such provision held to be invalid, illegal or unenforceable, that is not itself invalid, illegal or unenforceable) shall not in any way be affected or impaired thereby; (b) such provision
or provisions shall be deemed reformed to the extent necessary to conform to applicable law and to give the maximum effect to the intent of the parties hereto; and (c) to the fullest extent
possible, the provisions of this Agreement (including, without limitation, each portion of any Section of this Agreement containing any such provision held to be invalid, illegal or unenforceable,
that is not itself invalid, illegal or unenforceable) shall be construed so as to give effect to the intent manifested thereby.



	16.
	Exception to Right of Indemnification or Advancement of Expenses. Except as provided in Section 6(a) of this Agreement,
Indemnitee shall not be entitled to indemnification or advancement of Expenses under this Agreement with respect to any Proceeding brought by Indemnitee (other than a Proceeding by Indemnitee to
enforce his rights under this Agreement), or any claim therein, unless the bringing of such Proceeding or making of such claim shall have been approved by the Board of Directors or is otherwise
required under Section 145 of the Delaware General Corporation Law, regardless of whether such Indemnitee ultimately is determined to be entitled to such indemnification, advance expense
payment or insurance recovery, as the case may be.



	17.
	Identical Counterparts. This Agreement may be executed in one or more counterparts, each of which shall for all purposes be deemed to
be an original but all of which together shall constitute one and the same Agreement. Only one such counterpart signed by the party against whom enforceability is sought needs to be produced to
evidence the existence of this Agreement.



	18.
	Headings. The headings of the paragraphs of this Agreement are inserted for convenience only and shall not be deemed to constitute part
of this Agreement or to affect the construction thereof.



	19.
	Definitions. For purposes of this Agreement:



	a.
	"Affiliated
Person" of an Indemnitee shall include any director, officer, employee, controlling person (within the meaning of Section 15 of the Securities Act or
Section 20 of the Exchange Act), agent or fiduciary of such Indemnitee, and any stockholder, partner, partnership, corporation, limited liability company, association, joint stock company,
trust or joint venture, or similar entity controlling, controlled by or under common control with the entity or person that such Indemnitee represents in connection with such Indemnitee's service to
the Company. For these purposes, "control" means the possession, directly or indirectly, of the power to 





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direct
management and policies of a person or entity, whether through the ownership of voting securities, contract or otherwise. 



	b.
	"Change
in Control" means:



	i.
	The
acquisition by any person, corporation, partnership, limited liability company or other entity (a "Person", which term shall include a group within the meaning of
Section 13(d) of the Exchange Act) of ultimate beneficial ownership (within the meaning of Rule 13d-3 promulgated under the Exchange Act), directly or indirectly of 20% or
more of either (i) the then outstanding shares of common stock of the Company (the "Outstanding Company Common Stock") or (ii) the combined voting power of the then outstanding voting
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 of Control: (i) any such acquisition directly from the Company, except for acquisition of securities upon conversion of other securities of
the Company (ii) any such acquisition by the Company, (iii) any such 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 such acquisition by any corporation pursuant to a transaction which complies with clauses (1), (2) and (3) of subsection (iii) of this
Section 19(a); or



	ii.
	Individuals
who, as of the date hereof, constitute the Board (the "Incumbent Board") cease for any reason to constitute at least a majority of the Board; provided, however, that any
individual becoming a director subsequent to the date hereof whose election, or nomination for election, by the Company's stockholders, was approved by a vote of at least a majority of the directors
then comprising the Incumbent Board shall be considered as though such individual were a member of the Incumbent Board, but excluding, for this purpose, any such individual whose initial assumption of
office occurs 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



	iii.
	Consummation
of a reorganization, merger or consolidation or 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"), in each case, unless, following such Business Combination, (1) all or substantially all of the individuals and entities who were the beneficial owners, respectively, of
the Outstanding Company Common Stock and Outstanding Company Voting Securities immediately prior to such Business Combination beneficially own, directly or indirectly, immediately following such
Business Combination more than 50% of, respectively, the outstanding shares of common stock and the combined voting power of the then outstanding voting securities entitled to vote generally in the
election of directors, as the case may be, of the corporation resulting from such Business Combination (including, without limitation, a corporation which as a result of such transaction owns the
Company or all or substantially all of the Company's assets either directly or through one or more subsidiaries) 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, as the case may be, (2) no Person (excluding any corporation resulting from such Business
Combination or any employee benefit plan (or related trust) of the Company or such corporation resulting from such Business Combination) ultimately beneficially owns, directly or indirectly, 30% or
more of, respectively, the then outstanding shares of common stock of the corporation resulting from such Business Combination or the combined voting power of the then outstanding voting securities of
such corporation except to the extent that 






9







 



such
ownership existed prior to the Business Combination and (3) at least a majority of the members of the board of directors of the corporation resulting from such Business Combination were
members of the Incumbent Board at the time of the execution of the initial agreement, or of the action of the Board, providing for such Business Combination; or 



	iv.
	approval
by the stockholders of the Company of a complete liquidation or dissolution of the Company.






	c.
	"Corporate
Status" describes the status of a person who is or was a director, officer, employee, fiduciary or agent of the Company, or any subsidiary of the Company, or of any other
corporation, partnership, joint venture, trust, employee benefit plan or other enterprise which such person is or was serving at the request of the Company.



	d.
	"Disinterested
Director" means a director of the company who is not and was not a party to the Proceeding in respect of which indemnification is sought by Indemnitee.



	e.
	"Effective
Date" means                        .



	f.
	"Expenses"
shall include all reasonable attorneys' fees, retainers, court costs, transcript costs, fees of experts, witness fees, travel expenses, duplicating costs, printing and
binding costs, telephone charges, postage, delivery service fees, federal, state, local or foreign taxes imposed on Indemnitee as a result of the actual or deemed receipt of any payments under this
Agreement, and all other disbursements or expenses of the types customarily incurred in connection with prosecuting, defending, preparing to prosecute or defend, investigating, being or preparing to
be a witness, in, or otherwise participating in, a Proceeding.



	g.
	"Independent
Counsel" means a law firm, or a member of a law firm, that is experienced in matters of corporation law and neither presently is, nor in the past five years has been,
retained to represent: (i) the Company or Indemnitee in any matter material to either such party, or (ii) any other party to the Proceeding giving rise to a claim for indemnification
hereunder. Notwithstanding the foregoing, the term "Independent Counsel" shall not include any person who, under the applicable standards of professional conduct then prevailing, would have a conflict
of interest in representing either the Company or Indemnitee in an action to determine Indemnitee's rights under this Agreement. The Company agrees to pay the reasonable fees of the Independent
Counsel referred to above and to fully indemnify such counsel against any and all Expenses, claims, liabilities and damages arising out of or relating to this Agreement or its engagement pursuant
hereto.



	h.
	"Proceeding"
includes any threatened, pending or completed action, suit, arbitration, alternate dispute resolution mechanism, investigation, inquiry, administrative hearing or any
other actual, threatened or completed proceeding, whether brought by or in the right of the Company or otherwise and whether civil, criminal, administrative or investigative, in which Indemnitee was,
is, may be or will be involved as a party or otherwise, by reason of the fact that Indemnitee is or was a director or officer of the Company, or any subsidiary of the Company, by reason of any action
taken by him or of any inaction on his part while acting as director or officer of the Company, or by reason of the fact that he is or was serving at the request of the Company as a director, officer,
employee or agent of another corporation, partnership, joint venture, trust or other enterprise, including, without limitation, any threatened, pending or completed action, suit, arbitration,
alternate dispute resolution mechanism, investigation, inquiry, administrative hearing or any other actual, threatened or completed proceeding, whether brought by or in the right of the Company or
otherwise and whether civil, criminal, administrative or investigative, that arises or may arise, under the Securities Act of 1933, as amended (the "Securities Act"), the Exchange Act or any other 



10







 


federal
or state statutory law or regulation, at common law or otherwise, which relate directly or indirectly (i) to the registration, purchase, sale or ownership of any securities of the
Company, (ii) to any fiduciary obligation owed with respect to the Company and its stockholders or (iii) to any Series B Claim (as defined in Section 19(i) hereof);
in each case whether or not he is acting or serving in any such capacity at the time any liability or expense is incurred for which indemnification or advancement of expenses can be provided under
this Agreement; except one (i) initiated by an Indemnitee pursuant to Section 10 of this Agreement to enforce his right under this Agreement or (ii) pending on or before the
Effective Date. 



	i.
	"Series B
Claim" means any Proceeding related to Indemnitees' actions or omissions (or alleged actions or omissions) in connection with the purchase of Series B Preferred
Stock under that certain Series B Preferred Stock Purchase Agreement dated February 25, 2005 and the Investors (as defined therein).






	20.
	Enforcement.



	a.
	The
Company expressly confirms and agrees that it has entered into this Agreement and assumed the obligations imposed on it hereby in order to induce Indemnitee to serve as a director
and/or officer of the Company, and the Company acknowledges that Indemnitee is relying upon this Agreement in serving as a director and/or officer of the Company.



	b.
	This
Agreement constitutes the entire agreement between the parties hereto with respect to the subject matter hereof and supersedes all prior agreements and understandings, oral,
written and implied, between the parties hereto with respect to the subject matter hereof.






	21.
	Modification and Waiver. No supplement, modification or amendment of this Agreement shall be binding unless executed in writing by both
of the parties hereto. No waiver of any of the provisions of this Agreement shall be deemed or shall constitute a waiver of any other provisions hereof (whether or not similar) nor shall such waiver
constitute a continuing waiver.



	22.
	Attorneys' Fees. In the event that any action is instituted by an Indemnitee under this Agreement, or under any liability insurance
policies maintained by the Company, to enforce or interpret any of the terms hereof or thereof, any Indemnitee shall be entitled to be paid all Expenses incurred by such Indemnitee with respect to
such action, regardless of whether such Indemnitee is ultimately successful in such action, and shall be entitled to the advancement of Expenses with respect to such action, unless, as a part of such
action, a court of competent jurisdiction over such action determines that each of the material assertions made by such Indemnitee as a basis for such action was not made in good faith or was
frivolous.



	23.
	Notice by Indemnitee. Indemnitee agrees promptly to notify the Company in writing upon being served with any summons, citation,
subpoena, complaint, indictment, information or other document relating to any Proceeding or matter which may be subject to indemnification or advancement of Expenses covered hereunder. The failure of
Indemnitee to so notify the Company shall not relieve the Company of any obligation which it may have to Indemnitee under this Agreement or otherwise.



	24.
	Notices. All notices, requests, demands or other communications hereunder shall be in writing and shall be deemed to have been duly
given if (i) delivered by hand and receipted for by the party to whom said notice or other communication shall have been direct, or (ii) mailed by certified or registered mail with
postage prepaid, on the third business day after the date on which it is so mailed:



	a.
	If
to Indemnitee to: 
















[INDEMNITEE
CONTACT INFORMATION] 













11







 



















	b.
	If
to the Company to: 














Sirtris
Pharmaceuticals, Inc.

790 Memorial Drive, Suite 104

Cambridge, MA 02139 













	

	or
to such other address as may have been furnished to Indemnitee by the Company or to the Company by Indemnitee, as the case may be.



	25.
	Contribution.



	a.
	To
the fullest extent permissible under applicable law, if the indemnification provided for in this Agreement is unavailable to Indemnitee for any reason whatsoever, the Company, in
lieu of indemnifying Indemnitee, shall contribute to the amount incurred by Indemnitee, whether for judgments, fines, penalties, excise taxes, amounts paid or to be paid in settlement and/or for
Expenses, in connection with any claim relating to an indemnifiable event under this Agreement, in such proportion as is deemed fair and reasonable in light of all of the circumstances of such
Proceeding in order to reflect (i) the relative benefits received by the Company and Indemnitee as a result of the event(s) and/or transaction(s) giving cause to such Proceeding; or
(ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in
clause (i) above but also the relative fault of the Company (and its directors, officers, employees and agents) and Indemnitee in connection with such event(s) and/or transaction(s), as well as
any other relevant equitable considerations. In connection with the registration of the Company's securities, the relative benefits received by the Company and any Indemnitee shall be deemed to be in
the same respective proportions that the net proceeds from the offering (before deducting expenses) received by the Company and Indemnitee, in each case as set forth in the table on the cover page of
the applicable prospectus, bear to the aggregate public offering price of the securities so offered. The relative fault of the Company and any Indemnitee shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or
Indemnitee and the parties' relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.



	b.
	The
Company and each Indemnitee agree that it would not be just and equitable if contribution pursuant to this Section 25 were determined by pro rata or per capita allocation or
by any other method of allocation which does not take account of the equitable considerations referred to in Section 25(a) hereof. In connection with the registration of the Company's
securities, in no event shall an Indemnitee be required to contribute any amount under this Section 25 in excess of the net proceeds received by such Indemnitee from its sale of securities
under such registration statement. No person found guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any
person who was not found guilty of such fraudulent misrepresentation.






	26.
	Governing Law; Submission to Jurisdiction; Appointment of Agent for Service of Process. This Agreement and the legal relations among
the parties shall be governed by, and construed and enforced in accordance with, the laws of the State of Delaware, without regard to its conflict of laws rules. Except with respect to any arbitration
commenced by Indemnitee pursuant to Section 10(a) of this Agreement, the Company and Indemnitee hereby irrevocably and unconditionally (i) agree that any action or proceeding arising out
of or in connection with this Agreement shall be brought only in the Chancery Court of the State of Delaware (the "Delaware Court"), and not in any other state or federal court in the United States of
America or any court 


12







 

in
any other country, (ii) consent to submit to the exclusive jurisdiction of the Delaware Court for purposes of any action or proceeding arising out of or in connection with this Agreement,
(iii) appoint, to the extent such party is not a resident of the State of Delaware, irrevocably [                        ] as
its agent in the State of Delaware for acceptance of
legal process in connection with any such action or proceeding against such party with the same legal force and validity as if served upon such party personally within the State of Delaware,
(iv) waive any objection to the laying of venue of any such action or proceeding in the Delaware Court, and (v) waive, and agree not to plead or to make, any claim that any such action
or proceeding brought in the Delaware Court has been brought in an improper or otherwise inconvenient forum. 



	27.
	Miscellaneous. Use of the masculine pronoun shall be deemed to include usage of the feminine pronoun where appropriate. 


[Remainder of Page Intentionally Blank]


13







 

        IN
WITNESS WHEREOF, the parties hereto have executed this Agreement on the day and year first above written. 



	 	 	SIRTRIS PHARMACEUTICALS, INC.
	

 	
 	

By:	

 Name:

Title:
	

 	
 	

INDEMNITEE:
	

 	
 	

By:	

 Name:

Title:




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Exhibit 10.18