THEROX INC. INDEMNIFICATION AGREEMENT

Exhibit 10.21

THEROX INC.

INDEMNIFICATION AGREEMENT

This Indemnification Agreement (“Agreement”) is entered into as of the     th day of                     , 20    , by and between TherOx Inc., a Delaware corporation (the “Company”) and the Indemnitee identified on the signature page hereto (the “Indemnitee”).

R E C I T A L S

A. The Company and Indemnitee recognize the continued difficulty in obtaining liability insurance for the Company’s directors, officers, employees, agents and fiduciaries, the significant increases in the cost of such insurance and the general reductions in the coverage of such insurance.

B. The Company and Indemnitee further recognize the substantial increase in corporate litigation in general, subjecting directors, officers, employees, agents and fiduciaries to expensive litigation risks at the same time as the availability and coverage of liability insurance has been severely limited.

C. Indemnitee does not regard the current protection available as adequate under the present circumstances, and Indemnitee and other directors, officers, employees, agents and fiduciaries of the Company may not be willing to continue to serve in such capacities without additional protection.

D. The Company (i) desires to attract and retain the services of highly qualified individuals, such as Indemnitee, to serve the Company and, in part, in order to induce Indemnitee to continue to provide services to the Company and (ii) wishes to provide for the indemnification and advancing of expenses to each Indemnitee to the maximum extent permitted by law.

E. In view of the considerations set forth above, the Company desires that Indemnitee be indemnified by the Company as set forth herein.

NOW, THEREFORE, in consideration for Indeminitee’s services as an officer or director of the Company, the Company and Indemnitee hereby agree as follows:

1. Indemnification.

(a) Indemnification of Expenses. The Company shall indemnify and hold harmless Indemnitee (including his or her partners, employees and agents) to the fullest extent permitted by law if Indemnitee was or is or becomes a party to or witness or other participant in, or is threatened to be made a party to or witness or other participant in, any threatened, pending or completed action, suit, proceeding or alternative dispute resolution mechanism, or any hearing, inquiry or investigation, whether formal or informal, that Indemnitee in good faith believes might lead to the institution of any such action, suit, proceeding or alternative dispute resolution mechanism, whether civil, criminal, administrative, investigative or other (hereinafter a “Claim”) by reason of (or arising in part out of) any event or occurrence, which occurred before or after the date hereof, related to the fact that Indemnitee is or was a director, officer, employee, controlling person, agent or fiduciary of the Company, or any subsidiary of the Company, or is or was serving at the request of the Company as a director, officer, employee, controlling person, agent or fiduciary of another corporation, partnership, joint venture, trust or other enterprise, or by reason of any action or

inaction on the part of Indemnitee while serving in such capacity, and are directly related to Indemnitee’s service as an officer or director of the Company including, without limitation, any and all losses, claims, damages, expenses and liabilities, joint or several (including any investigation, legal and other expenses incurred in connection with, and any amount paid in settlement of, any action, suit proceeding or any claim asserted) under the Securities Act of 1933, as amended (the “Securities Act”), the Securities Exchange Act of 1934, as amended (the “Exchange Act”) or other federal or state statutory law or regulation, at common law or otherwise, which relate directly or indirectly to the registration, purchase, sale or ownership of any securities of the Company or to any fiduciary obligation owed with respect thereto against any and all expenses (including attorneys’ fees and all other costs, expenses and obligations incurred in connection with investigating, defending a witness in or participating in (including on appeal), or preparing to defend, be a witness in or participate in, any such action, suit, proceeding, alternative dispute resolution mechanism, hearing, inquiry or investigation), judgments, fines, penalties and amounts paid in settlement (if such settlement is approved in advance by the Company, which approval shall not be unreasonably withheld) of such Claim and any federal, state, local or foreign taxes imposed on Indemnitee as a result of the actual or deemed receipt of any payments under this Agreement (collectively, hereinafter “Expenses”), including all interest, assessments and other charges paid or payable in connection with or in respect of such Expenses. The knowledge, actions or failure to act of any director, officer, agent or employee of the Company or the Company itself shall not be imputed to Indemnitee for purposes of determining the right to indemnification hereunder.

(b) Contribution. If the indemnification provided for in Section 1(a) above for any reason is held by a court of competent jurisdiction to be unavailable to an Indemnitee in respect of any losses, claims, damages, expenses or liabilities referred to therein, then the Company, in lieu of indemnifying Indemnitee thereunder, shall contribute to the amount paid or payable by Indemnitee as a result of such losses, claims, damages, expenses or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company and the Indemnitee, 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 the Indemnitee in connection with the action or inaction which resulted in such losses, claims, damages, expenses or liabilities, 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 the 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 the 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 the 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 the Indemnitee and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

The Company and the Indemnitee agree that it would not be just and equitable if contribution pursuant to this Section 1(b) were determined by pro rata or per capita allocation or by securities, in no event shall an Indemnitee be required to contribute any amount under this Section 1(b) in excess of the lesser of (i) in the case of a director of the Company or any of its subsidiaries who is not an officer of the Company or any of such subsidiaries, the amount of fees paid to the director for serving as a director during the 12 months preceding the commencement of the Claim; or (ii) in the case of a director of the Company or any of its subsidiaries who is also an

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officer of the Company or any of such subsidiaries, the amount set forth in clause (i) plus 5% of the aggregate cash compensation paid to said director for service in such office(s) during the 12 months preceding the commencement of the Claim; (iii) in the case of an officer of the Company or any of its subsidiaries, 5% of the aggregate cash compensation paid to such officer for service in such office(s) during the 12 months preceding the commencement of such Claim; (iv) that proportion of the total of such losses, claims, damages or liabilities indemnified against equal to the proportion of the total securities sold under such registration statement which is being sold by such Indemnitee or (v) the proceeds received by Indemnitee from its sale of securities under such registration statement. Whether or not the indemnification provided in Sections 1 and 2 hereof is available, in respect of any threatened, pending or completed action, suit or proceeding in which the Company is jointly liable with Indemnitee (or would be if joined in such action, suit or proceeding), the Company shall pay, in first instance, the entire amount of any judgment or settlement of such action, suit or proceeding without requiring Indemnitee to contribute to such payment and the Company hereby waives and relinquishes any right to contribution it may have against Indemnitee. The Company shall not enter into any settlement of any action, suit or proceeding in which the Company is jointly liable with Indemnitee (or would be if joined in such action, suit or proceeding) unless such settlement provides for a full and final release of all claims asserted against Indemnitee. 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.

(c) Survival Regardless of Investigation. The indemnification and contribution provided for in this Section 1 will remain in full force and effect regardless of any investigation made by or on behalf of the Indemnitee or any officer, director, employee, agent or controlling person of the Indemnitee.

(d) Change in Control. The Company agrees that if there is a Change in Control of the Company (other than a Change in Control which has been approved by a majority of the Company’s Board of Directors who were directors immediately prior to such Change in Control) then, with respect to all matters thereafter arising concerning the rights of Indemnitee to payments of Expenses under this Agreement or any other agreement or under the Company’s Certificate of Incorporation or Bylaws as now or hereafter in effect, Independent Legal Counsel (as defined in Section 11(d) hereof) shall be selected by the Indemnitee and approved by the Company (which approval shall not be unreasonably withheld). Such counsel, among other things, shall render its written opinion to the Company and Indemnitee as to whether and to what extent Indemnitee would be permitted to be indemnified under applicable law. The Company agrees to abide by such opinion and to pay the reasonable fees of the Independent Legal Counsel referred to above and to fully indemnify such counsel against any and all expenses (including attorneys’ fees), claims, liabilities and damages arising out of or relating to this Agreement or its engagement pursuant hereto.

(e) Mandatory Payment of Expenses. Notwithstanding any other provision of this Agreement other than Section 9 hereof, to the extent that Indemnitee has been successful on the merits or otherwise, including, without limitation, the dismissal of an action without prejudice, in the defense of any action, suit, proceeding, inquiry or investigation referred to in Section 1(a) hereof or in the defense of any claim, issue or matter therein, Indemnitee shall be indemnified against all Expenses incurred by Indemnitee in connection therewith. No determination as to entitlement to indemnification under this Agreement need be made prior the final disposition of the proceeding. The termination of any proceeding or of any claim, issue or matter therein, by judgment, order, settlement (with or without court approval), conviction, or upon a plea of nolo contendere or its

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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 Indemnitee reasonably believed to be in or not opposed to the best interests of the Company and, with respect to any criminal proceeding, that Indemnitee had reasonable cause to believe that Indemnitee’s conduct was unlawful.

2. Expenses; Indemnification Procedure.

(a) Advancement of Expenses. The Company shall advance or pay on behalf of all Expenses incurred by Indemnitee provided that the Company has received an undertaking by or on behalf of Indemnitee, substantially in the form attached hereto as Exhibit A, to repay the amount so advanced to the extent that it is ultimately determined that such Expenses were not reasonable or that Indemnitee is not entitled to be indemnified by the Company under this Agreement or otherwise. Such repayment of advances shall be without interest or security for such repayment. The advances to be made hereunder shall be paid by the Company to Indemnitee as soon as practicable but in any event no later than twenty (20) days after written demand by Indemnitee therefor to the Company. If the Company fails to make timely payment hereunder, the Company shall also pay Indemnitee interest on such advance of Expenses at a rate of ten percent per annum.

(b) Notice/Cooperation by Indemnitee. Indemnitee shall, as a condition precedent to Indemnitee’s right to be indemnified under this Agreement, give the Company notice in writing as soon as practicable of any Claim made against Indemnitee for which indemnification will or could be sought under this Agreement. Notice to the Company shall be directed to the Chief Executive Officer of the Company at the address shown on the signature page of this Agreement (or such other address as the Company shall designate in writing to Indemnitee). Notice shall be deemed to have been provided herein without any action on the part of Indemnitee in the event the Company is a party to such proceeding. In addition, Indemnitee shall give the Company such information and cooperation as it may reasonably require and as shall be within Indemnitee’s power. Any indemnification provided hereunder shall be made no later than forty-five (45) days after receipt of the written request by Indemnitee. The Company shall promptly notify Indemnitee once the Company has received an offer or intends to make an offer to settle such proceeding and the Company shall provide Indemnitee as much time as reasonably practicable to consider such offer; provided, however, Indemnitee shall have no less than three (3) business days to consider the offer.

(c) Failure to Indemnify.

(i) If a claim under this Agreement, or any statute, or under any provision of the Company’s Certificate of Incorporation, or Bylaws providing for indemnification, is not paid in full by the Company, within forty-five (45) days after a written request for payment thereof has been received by the Company, Indemnitee may, but need not, at any time thereafter bring an action against the Company to recover the unpaid amount of the claim and, subject to Section 19 of this Agreement, if successful in whole or in part, Indemnitee shall also be entitled to be paid for the expense (including attorneys’ fees) of bringing such action.

(ii) It shall be a defense to such action (other than an action brought to enforce a claim for expenses incurred in connection with any action, suit or proceeding in advance of its final disposition) that Indemnitee has not met the standard of conduct which makes it permissible under applicable law for the Company to indemnify Indemnitee for the amount claimed, but the burden of proving such defense shall be on the Company and Indemnitee shall be entitled to receive

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interim payments of interim expenses pursuant to Section 2 hereof unless and until such defense may be finally adjudicated by court order or judgment from which no further right of appeal exists. It is the parties’ intention that if the Company contests Indemnitee’s right to indemnification, the question of Indemnitee’s right to indemnification shall be for the court to decide, and neither the failure of the Company (including its board of directors, independent legal counsel, or its stockholders) to have made a determination that indemnification of Indemnitee is proper in the circumstances because Indemnitee has met the applicable standard of conduct required by applicable law, nor an actual determination by the Company (including its board of directors, any committee or subgroup of the board of directors, independent legal counsel, or its stockholders) that Indemnitee has not met such applicable standard of conduct, shall create a presumption that Indemnitee has or has not met the applicable standard of conduct.

(d) Notice to Insurers. If, at the time of the receipt by the Company of a notice of a Claim pursuant to Section 2(b) hereof, the Company’s liability insurance may cover such Claim, the Company shall give prompt notice of the commencement of such Claim to the insurers in accordance with the procedures set forth in the respective policies. The Company shall thereafter take all necessary or desirable action to cause such insurers to pay, on behalf of Indemnitee, all amounts payable as a result of such action, suit, proceeding, inquiry or investigation in accordance with the terms of such policies. When and to the extent that such insurers pay Expenses, such Expenses shall be considered paid for purposes of this Agreement; and if the Indemnitee shall be compensated for the same Expenses by such insurers and the Company, the Indemnitee shall hold for the benefit of the Company and remit to the Company the insurance proceeds in excess of that necessary to pay such and all other Expenses.

(e) Selection of Counsel. In the event the Company shall be obligated hereunder to pay the Expenses of any Claim, the Company shall be entitled to assume the defense of such Claim, with counsel approved by the Indemnitee, which approval shall not be unreasonably withheld, upon the delivery to Indemnitee of written notice of its election to do so. After delivery of such notice, approval of such counsel by the Indemnitee and the retention of such counsel by the Company, the Company will not be liable to Indemnitee under this Agreement for any fees of counsel subsequently incurred by Indemnitee with respect to the same Claim; provided that, (i) the Indemnitee shall have the right to employ Indemnitee’s counsel in any such Claim at the Indemnitee’s expense, including counsel of Indemnitee’s choice to monitor the litigation in the event such counsel should assume the defense of Indemnitee, and such Company counsel shall co-operate with Indemnitee’s counsel and (ii) if (A) the employment of counsel by the Indemnitee has been previously authorized by the Company, (B) Indemnitee shall have reasonably concluded that there is likely to be a conflict of interest between the Company and Indemnitee in the conduct of any such defense, (C) the Company shall not continue to retain such counsel to defend such Claim or does not diligently prosecute the defense of such Claim, or (D) Indemnitee reasonably concludes that counsel engaged by the Company is not adequately representing Indemnitee, then the fees and expenses of the Indemnitee’s counsel shall be at the expense of the Company. The Company shall diligently prosecute the defense of such Claim. The Company shall have the right to settle any Claim against Indemnitee without the consent of such Indemnitee; provided, that (a) such settlement provides a full and unconditional release of Indemnitee in exchange for the payment of money only, all of which will be funded by the Company, (b) such settlement does not include an admission of guilt, and (c) such settlement does not restrict the future activities of Indemnitee or impose any on-going obligations (other than customary provisions such as confidentiality).

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3. Directors’ and Officers’ Insurance.

(a) The Company hereby covenants and agrees that, so long as Indemnitee shall continue to serve as a director or officer of the Company and thereafter so long as Indemnitee shall be subject to any possible Claim, the Company shall maintain in full force and effect directors’ and officers’ liability insurance in reasonable amounts from established and reputable insurers.

(b) In all policies of directors’ and officers’ liability insurance, Indemnitee shall be named as an insured in such a manner as to provide Indemnitee at least the same rights and benefits, subject to the same limitations, as are accorded to the Company’s directors or officers most favorably insured by such policy.

(c) The Company, or its successors, shall maintain in force any and all directors’ and officers’ liability insurance then maintained by the Company following a Change in Control of the Company for a period of six years thereafter.

(d) The Company shall provide Indemnitee with a copy of all directors’ and officers’ liability insurance applications, binders, policies, declarations, endorsements and other related materials, if such Indemnitee is an officer or director of the Company, and if such Indemnitee is a former director or officer of the Company then the Company shall provide all such materials upon the written request of Indemnitee for such materials

4. Additional Indemnification Rights; Nonexclusivity.

(a) Scope. The Company hereby agrees to indemnify Indemnitee to the fullest extent permitted by law, notwithstanding that such indemnification is not specifically authorized by the other provisions of this Agreement, the Company’s Certificate of Incorporation, the Company’s Bylaws or by statute. In the event of any change after the date of this Agreement in any applicable law, statute or rule which expands the right of a Delaware corporation to indemnify a member of its Board of Directors or an officer, employee, agent or fiduciary, it is the intent of the parties hereto that Indemnitee shall enjoy by this Agreement the greater benefits afforded by such change. In the event of any change in any applicable law, statute or rule which narrows the right of a Delaware corporation to indemnify a member of its Board of Directors or an officer, employee, agent or fiduciary, such change, to the extent not otherwise required by such law, statute or rule to be applied to this Agreement, shall have no effect on this Agreement or the parties’ rights and obligations hereunder except as set forth in Section 9(a) hereof.

(b) Nonexclusivity. The indemnification provided by this Agreement shall be in addition to any rights to which Indemnitee may be entitled under the Company’s Certificate of Incorporation, its Bylaws, any agreement, any vote of stockholders or disinterested directors, the Delaware General Corporation Law or otherwise. The indemnification provided under this Agreement shall continue as to Indemnitee for any action Indemnitee took or did not take while serving in an indemnified capacity even though the Indemnitee may have ceased to serve in such capacity.

5. No Duplication of Payments. The Company shall not be liable under this Agreement to make any payment in connection with any Claim made against Indemnitee to the extent such Indemnitee has otherwise actually received payment (under any insurance policy, Certificate of Incorporation, Bylaw or otherwise) of the amounts otherwise indemnifiable hereunder.

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6. Partial Indemnification. If Indemnitee is entitled under any provision of this Agreement to indemnification by the Company for any portion of Expenses incurred in connection with any Claim, but not, however, for all of the total amount thereof, the Company shall nevertheless indemnify Indemnitee for the portion of such Expenses to which Indemnitee is entitled.

7. No Assertion; Determination of Availability. The Company shall not assert in any action, suit or proceeding that the terms of this Agreement are not valid, binding or enforceable and that any procedures or presumptions made herein are not valid or enforceable. If the person or persons so empowered to make a determination pursuant to Section 2(a) hereof shall have failed to make the requested determination within ninety (90) days after judgment, order, settlement, dismissal, arbitration award, conviction, acceptance of a plea of nolo contendere or its equivalent, or other disposition or partial disposition of any proceeding or any other event that could enable the Company to determine Indemnitee’s entitlement to indemnification, the requisite determination that Indemnitee is entitled to indemnification shall be deemed to have been made.

8. Liability Insurance. To the extent the Company maintains liability insurance applicable to employees, control persons, agents or fiduciaries, Indemnitee shall be covered by such policies in such a manner as to provide Indemnitee at least the same rights and benefits as are accorded to the most favorably insured of the Company’s key employees, agents or fiduciaries, if Indemnitee is not an officer or director but is a key employee, agent, control person, or fiduciary.

9. Exceptions. Any other provision herein to the contrary notwithstanding, the Company shall not be obligated pursuant to the terms of the this Agreement:

(a) Excluded Action or Omissions. To indemnify Indemnitee for Indemnitee’s acts, omissions or transactions from which the Indemnitee may not be relieved of liability under applicable law;

(b) Claims Initiated by Indemnitee. To indemnify or advance expenses to Indemnitee with respect to Claims initiated or brought voluntarily by Indemnitee and not by way of defense, except (i) with respect to actions or proceedings to establish or enforce a right to indemnity under this Agreement or any other agreement or insurance policy including an action against the insurer for recovery under any insurance policy referred to herein or under the Company’s Certificate of Incorporation or Bylaws now or hereafter in effect relating to Claims for indemnifiable events, (ii) in specific cases if the Board of Directors has approved the initiation or bringing of such Claim, or (iii) as otherwise required under the applicable provisions of the Delaware General Corporation Law, regardless of whether Indemnitee ultimately is determined to be entitled to such indemnification, advance expense payment or insurance recovery, as the case may be;

(c) Lack of Good Faith. To indemnify Indemnitee for any expenses incurred by Indemnitee with respect to any proceeding instituted by Indemnitee to enforce or interpret this Agreement, if a court of competent jurisdiction determines that each of the material assertions made by Indemnitee in such proceeding was not made in good faith or was frivolous; or

(d) Claims Under Section 16(b). To indemnify Indemnitee for expenses and the payment of profits arising from the purchase and sale by Indemnitee of securities in violation of Section 16(b) of the Exchange Act or any similar successor statute after it has become certain that Indemnitee must repay all profits arising or losses avoided thereunder.

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10. 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 Indemnitee, Indemnitee’s estate, spouse, heirs, executors or personal or legal representatives after the expiration of two 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-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.

11. Construction of Certain Phrases.

(a) For purposes of this Agreement, references to the “Company” shall include, in addition to the resulting corporation, any constituent corporation (including any constituent of a constituent) absorbed in a consolidation or merger which, if its separate existence had continued, would have had power and authority to indemnify its directors, officers, employees, agents or fiduciaries, so that if Indemnitee is or was a director, officer, employee, agent, control person, or fiduciary of such constituent corporation, or is or was serving at the request of such constituent corporation as a director, officer, employee, control person, agent or fiduciary or another corporation, partnership, joint venture, employee benefit plan, trust or other enterprise, each Indemnitee shall stand in the same position under the provisions of this Agreement with respect to the resulting or surviving corporation as Indemnitee would have with respect to such constituent corporation if its separate existence had continued.

(b) For purposes of this Agreement, references to “other enterprises” shall include employee benefit plans; references to “fines” shall include any excise taxes assessed on Indemnitee with respect to an employee benefit plan; and references to “serving at the request of the Company” shall include any service as a director, office, employee, agent or fiduciary of the Company which imposes duties on, or involves services by, such director, officer, employee, agent or fiduciary with respect to an employee benefit plan, its participants or its beneficiaries; and if Indemnitee acted in good faith and in a manner Indemnitee reasonably believed to be in the interest of the participants and beneficiaries of an employee benefit plan, Indemnitee shall be deemed to have acted in a manner “not opposed to the best interests of the Company” as referred to in this Agreement.

(c) For purposes of this Agreement a “Change in Control” shall be deemed to have occurred if (i) any “person” (as such term in used in Sections 13(d) and 14(d) of the Exchange Act), other than a trustee or other fiduciary holding securities under an employee benefit plan of the Company or a corporation owned directly or indirectly by the stockholders of the Company in substantially the same proportions as their ownership of stock of the Company, (A) who is or becomes the beneficial owner, directly or indirectly, of securities of the Company representing 10% or more of the combined voting power of the Company’s then outstanding Voting Securities (as defined in Section 11(e) below), increases his or her beneficial ownership of such securities by 5% or more over the percentage so owned by such person, or (B) becomes the “beneficial owner” (as defined in Rule 13d-3 under said Act), directly or indirectly, of securities of the Company representing more than 20% of the total voting power represented by the Company’s then outstanding Voting Securities, (ii) during any period of two consecutive years, individuals who at the beginning of such period constitute the Board of Directors of the Company and any new director

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whose election by the Board of Directors or nomination for election by the Company’s stockholders was approved by a vote of at least two-thirds of the directors then still in office who either were directors at the beginning of the period or whose election or nomination for election was previously so approved, cease for any reason to constitute a majority thereof, or (iii) the stockholders of the Company approve a merger or consolidation of the Company with any other corporation other than a merger or consolidation which would result in the Voting Securities of the Company outstanding immediately prior thereto continuing to represent (either by remaining outstanding or by being converted into Voting Securities of the surviving entity) at least 80% of the total voting power represented by the Voting Securities of the Company or such surviving entity outstanding immediately after such merger or consolidation, or the stockholders of the Company approve a plan of complete liquidation of the Company or an agreement for the sale or disposition by the Company of (in one transaction or a series of transactions) all or substantially all of the Company’s assets.

(d) For purposes of this Agreement, “Independent Legal Counsel” shall mean an attorney or firm of attorneys, selected in accordance with the provisions of Section 1(d) hereof, who shall not have otherwise performed services for the Company or Indemnitee within the last three years (other than with respect to matters concerning the right of Indemnitee under this Agreement, or of other indemnitees under similar indemnity agreements). Notwithstanding the foregoing, the term Independent Legal 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 right to indemnification under this Agreement.

(e) For purposes of this Agreement, “Voting Securities” shall mean any securities of the Company that vote generally in the election of directors.

12. Remedies. In the event that (a) a determination is made that Indemnitee is not entitled to indemnification, (b) advances for Expenses are not made when and as required by this Agreement, (c) payment has not been timely made pursuant to this Agreement or (d) Indemnitee otherwise seeks enforcement of this Agreement, Indemnitee shall be entitled to a final adjudication in an appropriate court of the State of Delaware of his or her entitlement to such indemnification or advance. Alternatively, Indemnitee at his or her option may seek an award in arbitration. If the parties are unable to agree on an arbitrator, the parties shall provide JAMS Endispute (“JAMS”) with a statement of the nature of the dispute and the desired qualifications of the arbitrator. JAMS will then provide a list of three available arbitrators. Each party may strike one of the names on the list, and the remaining person will serve as the arbitrator. If both parties strike the same person, JAMS will select the arbitrator from the other two names. The arbitration award shall be made within 90 days following the demand for arbitration. Except as set forth herein, the provisions of Delaware law shall apply to any such arbitration. The Company shall not oppose Indemnitee’s right to seek any such adjudication or arbitration award. In any such proceeding or arbitration Indemnitee shall be presumed to be entitled to indemnification under this Agreement and the Company shall have the burden of proof to overcome that presumption.

13. Injunctive Relief. The Company and Indemnitee agree herein that a monetary remedy for breach of this Agreement, at some later date, will be inadequate, impracticable and difficult of proof, and further agree that such breach would cause Indemnitee irreparable harm. Accordingly, the Company and Indemnitee agree that Indemnitee shall be entitled to temporary and permanent injunctive relief to enforce this Agreement without the necessity of proving actual damages or irreparable harm. The Company and Indemnitee further agree that Indemnitee shall be

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entitled to such injunctive relief, including temporary restraining orders, preliminary injunctions and permanent injunctions, without the necessity of posting bond or other undertaking in connection therewith. Any such requirement of bond or undertaking is hereby waived by the Company, and the Company acknowledges that in the absence of such a waiver, a bond or undertaking may be required by the court.

14. Duration and Scope of Agreement. This Agreement shall continue so long as Indemnitee shall be subject to any possible Claim eligible for indemnification pursuant to the terms of this Agreement and shall be applicable to Claims commenced or continued after execution of this Agreement, whether arising from acts or omissions occurring before or after such execution.

15. Establishment of Trust. In order to secure the obligations of the Company to indemnify and to advance Expenses to Indemnitee pursuant to this Agreement, upon a Change of Control of the Company, the Company or its successor or assign shall establish a Trust (the “Trust”) for the benefit of the Indemnitee, the trustee (the “Trustee”) of which shall be chosen by the Company and which is reasonably acceptable to the Indemnitee. Thereafter, from time to time, upon receipt of a written request from Indemnitee, the Company shall fund the Trust in amounts sufficient to satisfy any and all Expenses reasonably anticipated at the time of such request for which the Company may indemnify Indemnitee hereunder. The amount or amounts to be deposited in the Trust pursuant to the foregoing funding obligation shall be determined by mutual agreement of the Indemnitee and the Company or, if the Company and the Indemnitee are unable to reach such an agreement, by Independent Counsel selected jointly by the Company and the Indemnitee. The terms of the Trust shall provide that except upon the consent of the Indemnitee and the Company, (i) the Trust shall not be revoked or the principal thereof invaded, without the written consent of the Indemnitee, (ii) the Trustee shall advance to the Indemnitee, within twenty (20) days of a request by the Indemnitee, any and all Expenses, the Indemnitee hereby agreeing to reimburse the Trustee of the Trust for all Expenses so advanced if a final determination is made by a court in a final adjudication from which there is no further right of appeal that the Indemnitee is not entitled to be indemnified under this Agreement, (iii) the Trust shall continue to be funded by the Company in accordance with the funding obligations set forth in this Section, (iv) the Trustee shall promptly pay to the Indemnitee any amounts to which the Indemnitee shall be entitled pursuant to this Agreement, and (v) all unexpended funds in the Trust shall revert to the Company upon a final determination by Independent Counsel selected by Indemnitee or a court of competent jurisdiction that Indemnitee has been fully indemnified with respect to the Proceeding giving rise to the funding of the Trust under the terms of this Agreement. The establishment of the Trust shall not, in any way, diminish the Company’s obligation to indemnify Indemnitee against Expenses and Claims to the full extent required by this Agreement.

16. Indemnitee’s Obligations. The Indemnitee shall promptly advise the Company in writing of the institution of any investigation, claim, action, suit or proceeding which is or may be subject to this Agreement and keep the Company generally informed of, and consult with the Company with respect to, the status of any such investigation, claim, action, suit or proceeding; provided, however, Indemnitee shall not have any obligation hereunder to the extent the Company is a party to such investigation, claim, action, suit or proceeding and is fully informed of such action.

17. Counterparts. This Agreement may be executed in one or more counterparts, each of which shall constitute an original.

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18. Binding Effect; Successors and Assigns. This Agreement shall be binding upon and inure to the benefit of and be enforceable by the parties hereto and their respective successors, assigns, including any direct or indirect successor by purchase, merger, consolidation or otherwise to all or substantially all of the business and/or assets of the Company, spouses, heirs, and personal and legal representatives. The Company shall require and cause any successor (whether direct or indirect by purchase, merger, consolidation or otherwise) to all or substantially all of the business and/or assets of the Company, by written agreement in form and substance satisfactory to Indemnitee, expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Company would be required to perform if no such succession had taken place. This Agreement shall continue in effect with respect to Claims relating to indemnifiable events regardless of whether Indemnitee continues to serve as a director, officer, employee, agent, controlling person, or fiduciary of the Company or of any other enterprise at the Company’s request.

19. Attorneys’ Fees. In the event that any action is instituted by 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 Indemnitee 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 Indemnitee as a basis for such action was made in bad faith or was frivolous. In the event of an action instituted by or in the name of the Company under this Agreement to enforce or interpret any of the terms of this Agreement, the Indemnitee shall be entitled to be paid all Expenses incurred by Indemnitee in defense of such action (including costs and expenses incurred with respect to Indemnitee counterclaims and cross-claims made in such action), unless, as a part of such action, a court having jurisdiction over such action determines that each of Indemnitee’s material defenses to such action was made in bad faith or was frivolous.

20. Presumption of Good Faith. Indemnitee shall be deemed to have acted in good faith as it relates to any action on the part of Indemnitee as an officer or director of the Company if an Indemnitee’s action is based on the records or books of account of the Company, including financial statements, or on information provided to Indemnitee by the officers of the Company in the course of their duties, or on the advice of legal counsel for the Company or the Board of Directors or legal counsel selected by any committee of the Board of Directors or on information or records given or provided by an appraiser or investment banker, compensation consultant, or other expert selected with reasonable care by the Company. The provisions of this Section 20 shall not be deemed exclusive or to limit in anyway the other circumstances in which Indemnitee may be deemed to have met the applicable standard of conduct.

21. Information. If the Indemnitee is the subject of or is otherwise implicated or involved in any way during an investigation or inquiry, whether formal or informal, the Company shall so notify the Indemnitee within a reasonable time of becoming aware of such inquiry or investigation. The Company shall provide Indemnitee with a copy of any information furnished to any third parties (other than independent counsel of the Company or the Board of Directors or a subcommittee of the Board of Directors) at the direction of the Company (including at the direction of the Board of Directors or any subcommittee thereof) concerning the investigation at the same time such information is being provided to said third parties. With respect to officers of the Company, the rights provided by this Section 21 shall lapse twelve months after the separation of Indemnitee from the Company.

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22. Notice. All notices and other communications required or permitted hereunder shall be in writing, shall be effective when given, and shall in any event be deemed to be given (a) five (5) days after deposit with the U.S. Postal Service or other applicable postal service, if delivered by first class mail, postage prepaid, (b) upon delivery, if delivered by hand, (c) one business day after the business day of deposited with Federal Express or similar overnight courier, freight prepaid, or (d) one day after the business day of delivery by facsimile transmission, if deliverable by facsimile transmission, with copy by first class mail, postage prepaid, and shall be addressed if to Indemnitee, at Indemnitee’s address as set forth beneath the Indemnitee’s signature to this Agreement and if to the Company at the address of its principal corporate offices (attention: Secretary) or at such other address as such party may designate by ten days’ advance written notice to the other party hereto.

23. Consent to Jurisdiction. The Company and Indemnitee each hereby irrevocably consent to the jurisdiction of the courts of the State of Delaware for all purposes in connection with any action or proceeding which arises out of or relates to this Agreement and agree that any action instituted under this Agreement shall be commenced, prosecuted and continued only in the state courts of the State of Delaware, which shall be the exclusive and only proper forum for adjudicating such a claim.

24. Severability. The provisions of this Agreement shall be severable in the event that any of the provisions hereof (including any provision within a single section, paragraph or sentence) are held by a court of competent jurisdiction to be invalid, void or otherwise unenforceable, and the remaining provisions shall remain enforceable to the fullest extent permitted by law. Furthermore, to the fullest extent possible, the provisions of this Agreement (including, without limitations, each portion of this Agreement containing any provision held to be invalid, void or otherwise unenforceable, that is not itself invalid, void or unenforceable) shall be construed so as to give effect to the intent manifested by the provision held invalid, illegal or unenforceable.

25. Choice of Law. This Agreement shall be governed by and its provisions construed and enforced in accordance with the laws of the State of Delaware as applied to contracts between Delaware residents, entered into and to be performed entirely within the State of Delaware without regard to the conflict of laws principles thereof.

26. Subrogation. In the event of 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 documents required and shall do all acts that may be necessary to secure such rights and to enable the Company effectively to bring suit to enforce such rights.

27. Amendment and Termination. No amendment, modification, termination or cancellation of this Agreement shall be effective unless it is in writing signed by all 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.

28. Integration and Entire Agreement. This Agreement sets forth the entire understanding between the parties hereto and supersedes and merges all previous written and oral negotiations, commitments, understandings and agreements relating to the subject matter hereof between the parties hereto.

29. No Construction as Employment Agreement. Nothing contained in this Agreement shall be construed as giving Indemnitee any right to be retained in the employ of the Company or any of its subsidiaries.

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first above written.

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EXHIBIT A

UNDERTAKING AGREEMENT

This UNDERTAKING AGREEMENT is made on                     ,         , between TherOx, Inc., a Delaware corporation (the “Company”) and                             , an officer and/or member of the board of directors of the Company (“Indemnitee”).

WHEREAS, Indemnitee may become involved in investigations, claims, actions, suits or proceedings which have arisen or may arise in the future as a result of Indemnitee’s service to the Company; and

WHEREAS, Indemnitee desires that the Company pay any and all expenses (including, but not limited to, attorneys’ fees and court costs) actually and reasonably incurred by Indemnitee or on Indemnitee’s behalf in defending or investigating any such suits or claims and that such payment be made in advance of the final disposition of such investigations, claims, actions, suits or proceedings to the extent that Indemnitee has not been previously reimbursed by insurance; and

WHEREAS, the Company is willing to make such payments but, in accordance with Section 145 of the General Corporation Law of the State of Delaware, the Company may make such payments only if it receives an undertaking to repay from Indemnitee; and

WHEREAS, Indemnitee is willing to give such an undertaking;

NOW, THEREFORE, in consideration of the mutual promises contained herein, the parties agree as follows:

1. In regard to any payments made by the Company to Indemnitee pursuant to the terms of the Indemnification Agreement dated                  ,         , between the Company and Indemnitee, Indemnitee hereby undertakes and agrees to repay to the Company any and all amounts so paid promptly and in any event within thirty (30) days after the disposition, including any appeals, of any litigation or threatened litigation on account of which payments were made, but only to the extent that Indemnitee is ultimately found not to be entitled to be indemnified by the Company under the Bylaws of the Company and Section 145 of the General Corporation Law of the State of Delaware, or other applicable law.

2. This Agreement shall not affect in any manner rights which Indemnitee may have against the Company, any insurer or any other person to seek indemnification for or reimbursement of any expenses referred to herein or any judgment which may be rendered in any litigation or proceeding.

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IN WITNESS WHEREOF, the parties have caused this Agreement to be executed on the date first above written.

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