IMPAC MEDICAL SYSTEMS, INC. CHANGE OF CONTROL SEVERANCE AGREEMENT

Exhibit 10.1

IMPAC MEDICAL SYSTEMS, INC.

CHANGE OF CONTROL SEVERANCE AGREEMENT

This Change of Control Severance Agreement (the “Agreement”) is made and entered into effective as of January 17, 2005 (the “Effective Date”), by and between Kendra Borrego (the “Employee”) and IMPAC Medical Systems, Inc., a Delaware corporation (the “Company”). Certain capitalized terms used in this Agreement are defined in Section 1 below.

R E C I T A L S

A. It is expected that the Company from time to time will consider the possibility of a Change of Control. The Board of Directors of the Company (the “Board”) recognizes that such consideration can be a distraction to the Employee and can cause the Employee to consider alternative employment opportunities.

B. The Board believes that it is in the best interests of the Company and its shareholders to provide the Employee with an incentive to continue her employment and to maximize the value of the Company upon a Change of Control for the benefit of its shareholders.

C. In order to provide the Employee with enhanced financial security and sufficient encouragement to remain with the Company notwithstanding the possibility of a Change of Control, the Board believes that it is imperative to provide the Employee with certain severance benefits upon the Employee’s termination of employment following a Change of Control.

AGREEMENT

In consideration of the mutual covenants herein contained and the continued employment of Employee by the Company, the parties agree as follows:

1. Definition of Terms. The following terms referred to in this Agreement shall have the following meanings:

(a) Cause. “Cause” shall mean (i) any act of personal dishonesty taken by the Employee in connection with her responsibilities as an employee which is intended to result in substantial personal enrichment of the Employee, (ii) Employee’s conviction of a felony which the Board reasonably believes has had or will have a material detrimental effect on the Company’s reputation or business, (iii) a willful act by the Employee which constitutes misconduct and is injurious to the Company, and (iv) continued willful violations by the Employee of the Employee’s obligations to the Company after there has been delivered to the Employee a written demand for performance from the Company which describes the basis for the Company’s belief that the Employee has not substantially performed her duties.

(b) Change of Control. “Change of Control” shall mean the occurrence of any of the following events:

(i) the approval by shareholders of the Company of 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) more than fifty percent (50%) of the total voting power represented by the voting securities of the Company or such surviving entity outstanding immediately after such merger or consolidation;

(ii) any approval by the shareholders of the Company of a plan of complete liquidation of the Company or an agreement for the sale or disposition by the Company of all or substantially all of the Company’s assets;

(iii) any “person” (as such term is used in Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended) becoming the “beneficial owner” (as defined in Rule 13d-3 under said Act), directly or indirectly, of securities of the Company representing 50% or more of the total voting power represented by the Company’s then outstanding voting securities; or

(iv) a change in the composition of the Board, as a result of which fewer than a majority of the directors are Incumbent Directors. “Incumbent Directors” shall mean directors who either (A) are directors of the Company as of the date hereof, or (B) are elected, or nominated for election, to the Board with the affirmative votes of at least a majority of those directors whose election or nomination was not in connection with any transaction described in subsections (i), (ii) or (iii) or in connection with an actual or threatened proxy contest relating to the election of directors of the Company.

(c) Compensation Continuation Period. “Compensation Continuation Period” shall mean the period of time commencing with termination of the Employee’s employment as a result of Involuntary Termination at any time within twelve (12) months after a Change of Control and ending with the date six (6) months following the date of the Employee’s termination.

(d) Involuntary Termination. “Involuntary Termination” shall mean (i) without the Employee’s express written consent, a significant reduction of the Employee’s duties, position or responsibilities relative to the Employee’s duties, position or responsibilities in effect immediately prior to such reduction, or the removal of the Employee from such position, duties and responsibilities, unless the Employee is provided with comparable duties, position and responsibilities; (ii) without the Employee’s express written consent, a substantial reduction, without good business reasons, of the facilities and perquisites (including office space and location) available to the Employee immediately prior to such reduction; (iii) a reduction by the Company of the Employee’s base salary or target bonus as in effect immediately prior to such reduction; (iv) a material reduction by the Company in the kind or level of employee benefits to which the Employee is entitled immediately prior to such reduction with the result that the Employee’s overall benefits package is significantly reduced; (v) without the Employee’s express written consent, the relocation of the Employee to a facility or a location more than fifty (50) miles from her current location; (vi) any purported termination of the Employee by the Company which is not effected for Cause or for which the grounds relied upon are not valid; or (vii) the failure of the Company to obtain the assumption of this Agreement by any successors contemplated in Section 6 below.

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2. Term of Agreement. This Agreement shall terminate upon the date that all obligations of the parties hereto under this Agreement have been satisfied.

3. At-Will Employment. The Company and the Employee acknowledge that the Employee’s employment is and shall continue to be at-will, as defined under applicable law. If the Employee’s employment terminates for any reason, the Employee shall not be entitled to any payments, benefits, damages, awards or compensation other than as provided by this Agreement, or as may otherwise be established under the Company’s then existing employee benefit plans or policies at the time of termination.

4. Change of Control and Severance Benefits.

(a) Termination Following A Change of Control.

(i) Severance Payments. If the Employee’s employment with the Company terminates as a result of an Involuntary Termination at any time within twelve (12) months after a Change of Control, then the Employee shall be entitled to receive continuing payments of severance pay during the Compensation Continuation Period at a rate equal to one hundred (100)% of the Employee’s base salary (as in effect immediately prior to the Change of Control). Such severance payments shall be paid bi-weekly in accordance with the Company’s normal payroll practices. In addition, during the Compensation Continuation Period, the Company shall continue to make available to the Employee and Employee’s spouse and dependents covered under any group health plans or life insurance plans of the Company on the date of such termination of employment, all group health, life and other similar insurance plans in which Employee or such Covered Dependents participate on the date of the Employee’s termination.

(ii) Option Acceleration. If the Employee’s employment with the Company terminates as a result of an Involuntary Termination at any time within twelve (12) months after a Change of Control, then each option granted to the Employee by the Company (the “Options”) shall immediately become vested and exercisable in full.

(iii) Conditions. All payments and benefits provided under this Section 4 are conditioned on Employee’s continuing compliance with this Agreement and the Company’s policies and Employee’s execution of a release of claims and covenant not to sue substantially in the form provided in Exhibit A upon termination of employment.

(iv) Other Termination. If the Employee’s employment with the Company terminates other than as a result of an Involuntary Termination at any time within twelve (12) months after a Change of Control, then the Employee shall not be entitled to receive severance or other benefits hereunder, but may be eligible for those benefits (if any) as may then be established under the Company’s then existing severance and benefits plans and policies at the time of such termination.

(b) Termination Apart from a Change of Control. If the Employee’s employment with the Company terminates for any or no reason other than within twelve (12) months following a Change of Control, then the Employee shall not be entitled to receive severance or other benefits hereunder, but may be eligible for those benefits (if any) as may then be established under the Company’s then existing severance and benefits plans and policies at the time of such termination.

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(c) Accrued Wages and Vacation; Expenses. Without regard to the reason for, or the timing of, Employee’s termination of employment: (i) the Company shall pay the Employee any unpaid base salary due for periods prior to the date of termination; (ii) the Company shall pay the Employee all of the Employee’s accrued and unused vacation through the date of termination; and (iii) following submission of proper expense reports by the Employee, the Company shall reimburse the Employee for all expenses reasonably and necessarily incurred by the Employee in connection with the business of the Company prior to the date of termination. These payments shall be made promptly upon termination and within the period of time mandated by law.

5. Successors.

(a) Company’s Successors. Any successor (whether direct or indirect and whether by purchase, lease, merger, consolidation, liquidation or otherwise) to all or substantially all of the Company’s business and/or assets, shall be obligated to perform this Agreement in the same manner and to the same extent as the Company would be required to perform it in the absence of a succession.

(b) Employee’s Successors. Without the written consent of the Company, Employee shall not assign or transfer this Agreement or any right or obligation under this Agreement to any other person or entity. Notwithstanding the foregoing, the terms of this Agreement and all rights of Employee hereunder shall inure to the benefit of, and be enforceable by, Employee’s personal or legal representatives, executors, administrators, successors, heirs, distributees, devisees and legatees.

6. Notices.

(a) General. Notices and all other communications contemplated by this Agreement shall be in writing and shall be deemed to have been duly given when personally delivered or when mailed by U.S. registered or certified mail, return receipt requested and postage prepaid. In the case of the Employee, mailed notices shall be addressed to him at the home address that she most recently communicated to the Company in writing. In the case of the Company, mailed notices shall be addressed to its corporate headquarters, and all notices shall be directed to the attention of its Secretary.

(b) Notice of Termination. Any termination by the Company for Cause or by the Employee as a result of a voluntary resignation or an Involuntary Termination shall be communicated by a notice of termination to the other party hereto given in accordance with this Section. Such notice shall indicate the specific termination provision in this Agreement relied upon, shall set forth in reasonable detail the facts and circumstances claimed to provide a basis for termination under the provision so indicated. The failure by the Employee to include in the notice any fact or circumstance which contributes to a showing of Involuntary Termination shall not waive any right of the Employee hereunder or preclude the Employee from asserting such fact or circumstance in enforcing her rights hereunder.

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7. Arbitration.

(a) Any dispute or controversy arising out of, relating to, or in connection with this Agreement, or the interpretation, validity, construction, performance, breach, or termination thereof, shall be settled by binding arbitration to be held in San Francisco, California, in accordance with the National Rules for the Resolution of Employment Disputes then in effect of the American Arbitration Association (the “Rules”). The arbitrator may grant injunctions or other relief in such dispute or controversy. The decision of the arbitrator shall be final, conclusive and binding on the parties to the arbitration. Judgment may be entered on the arbitrator’s decision in any court having jurisdiction.

(b) The arbitrator(s) shall apply California law to the merits of any dispute or claim, without reference to conflicts of law rules. The arbitration proceedings shall be governed by federal arbitration law and by the Rules, without reference to state arbitration law. Employee hereby consents to the personal jurisdiction of the state and federal courts located in California for any action or proceeding arising from or relating to this Agreement or relating to any arbitration in which the parties are participants.

(c) Employee understands that nothing in this Section modifies Employee’s at-will employment status. Either Employee or the Company can terminate the employment relationship at any time, with or without cause.

(d) EMPLOYEE HAS READ AND UNDERSTANDS THIS SECTION, WHICH DISCUSSES ARBITRATION. EMPLOYEE UNDERSTANDS THAT SUBMITTING ANY CLAIMS ARISING OUT OF, RELATING TO, OR IN CONNECTION WITH THIS AGREEMENT, OR THE INTERPRETATION, VALIDITY, CONSTRUCTION, PERFORMANCE, BREACH OR TERMINATION THEREOF TO BINDING ARBITRATION TO THE EXTENT PERMITTED BY LAW, AND THAT THIS ARBITRATION CLAUSE CONSTITUTES A WAIVER OF EMPLOYEE’S RIGHT TO A JURY TRIAL AND RELATES TO THE RESOLUTION OF ALL DISPUTES RELATING TO ALL ASPECTS OF THE EMPLOYER/EMPLOYEE RELATIONSHIP, INCLUDING BUT NOT LIMITED TO, THE FOLLOWING CLAIMS:

(i) ANY AND ALL CLAIMS FOR WRONGFUL DISCHARGE OF EMPLOYMENT; BREACH OF CONTRACT, BOTH EXPRESS AND IMPLIED; BREACH OF THE COVENANT OF GOOD FAITH AND FAIR DEALING, BOTH EXPRESS AND IMPLIED; NEGLIGENT OR INTENTIONAL INFLICTION OF EMOTIONAL DISTRESS; NEGLIGENT OR INTENTIONAL MISREPRESENTATION; NEGLIGENT OR INTENTIONAL INTERFERENCE WITH CONTRACT OR PROSPECTIVE ECONOMIC ADVANTAGE; AND DEFAMATION.

(ii) ANY AND ALL CLAIMS FOR VIOLATION OF ANY FEDERAL STATE OR MUNICIPAL STATUTE, INCLUDING, BUT NOT LIMITED TO, TITLE VII OF THE CIVIL RIGHTS ACT OF 1964, THE CIVIL RIGHTS ACT OF 1991, THE AGE DISCRIMINATION IN EMPLOYMENT ACT OF 1967, THE AMERICANS WITH DISABILITIES ACT OF 1990, THE FAIR LABOR STANDARDS ACT, THE CALIFORNIA FAIR EMPLOYMENT AND HOUSING ACT, AND LABOR CODE SECTION 201, et seq;

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(iii) ANY AND ALL CLAIMS ARISING OUT OF ANY OTHER LAWS AND REGULATIONS RELATING TO EMPLOYMENT OR EMPLOYMENT DISCRIMINATION.

8. Miscellaneous Provisions.

(a) No Duty to Mitigate. The Employee shall not be required to mitigate the amount of any payment contemplated by this Agreement, nor shall any such payment be reduced by any earnings that the Employee may receive from any other source.

(b) Waiver. No provision of this Agreement may be modified, waived or discharged unless the modification, waiver or discharge is agreed to in writing and signed by the Employee and by an authorized officer of the Company (other than the Employee). No waiver by either party of any breach of, or of compliance with, any condition or provision of this Agreement by the other party shall be considered a waiver of any other condition or provision or of the same condition or provision at another time.

(c) Integration. This Agreement represents the entire agreement and understanding between the parties as to the subject matter herein and supersede all prior or contemporaneous agreements, whether written or oral.

(d) Choice of Law. The validity, interpretation, construction and performance of this Agreement shall be governed by the internal substantive laws, but not the conflicts of law rules, of the State of California.

(e) Severability. The invalidity or unenforceability of any provision or provisions of this Agreement shall not affect the validity or enforceability of any other provision hereof, which shall remain in full force and effect.

(f) Employment Taxes. All payments made pursuant to this Agreement shall be subject to withholding of applicable income and employment taxes.

(g) Counterparts. This Agreement may be executed in counterparts, each of which shall be deemed an original, but all of which together will constitute one and the same instrument.

(h) Voluntary Execution of Agreement. This Agreement is executed voluntarily and without any duress or undue influence on the part or behalf of the parties hereto, with the full intent of releasing all claims. Employee acknowledges that:

(i) She has read this Agreement;

(ii) She has been represented in the preparation, negotiation, and execution of this Agreement by legal counsel of her own choice or that she has voluntarily declined to seek such counsel;

(iii) She understands the terms and consequences of this Agreement and of the releases it contains;

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(iv) She is fully aware of the legal and binding effect of this Agreement.

IN WITNESS WHEREOF, each of the parties has executed this Agreement, in the case of the Company by its duly authorized officer, as of the day and year first above written.

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EXHIBIT A

Form of Release of Claims and Covenant Not To Sue

In consideration of the payments and other benefits that IMPAC Medical Systems, Inc. (the “Company”) is providing to Kendra Borrego (“Employee”) under the Change in Control Severance Agreement entered into by and between Employee and the Company, dated January 17, 2005, the Employee, on his/her own behalf and on behalf of Employee’s representatives, agents, heirs and assigns, waives, releases, discharges and promises never to assert any and all claims, demands, actions, costs, rights, liabilities, damages or obligations of every kind and nature, whether known or unknown, suspected or unsuspected that Employee ever had, now have or might have as of the date of Employee’s termination of employment with the Company against the Company or its predecessors, parent, affiliates, subsidiaries, stockholders, owners, directors, officers, employees, agents, attorneys, insurers, successors, or assigns (including all such persons or entities that have a current and/or former relationship with the Company) for any claims arising from or related to Employee’s employment with the Company, its parent or any of its affiliates and subsidiaries and the termination of that employment.

These released claims also specifically include, but are not limited to, any claims arising under any federal, state and local statutory or common law, such as (as amended and as applicable) Title VII of the Civil Rights Act, the Age Discrimination in Employment Act, the Americans With Disabilities Act, the Employee Retirement Income Security Act, the Family Medical Leave Act, the Equal Pay Act, the Fair Labor Standards Act, the Industrial Welfare Commission’s Orders, the California Fair Employment and Housing Act, the California Constitution, the California Government Code, the California Labor Code and any other federal, state or local constitution, law, regulation or ordinance governing the terms and conditions of employment or the termination of employment, and the law of contract and tort and any claim for attorneys’ fees.

Furthermore, the Employee acknowledges that this waiver and release is knowing and voluntary and that the consideration given for this waiver and release is in addition to anything of value to which Employee was already entitled. Employee acknowledges that there may exist facts or claims in addition to or different from those which are now known or believed by Employee to exist. Nonetheless, this Agreement extends to all claims of every nature and kind whatsoever, whether known or unknown, suspected or unsuspected, past or present. Employee also expressly waives the provisions of California Civil Code section 1542, which provides: “A general release does not extend to claims which the creditor does not know or suspect to exist in his favor at the time of executing the release, which if known by him/her must have materially affected his settlement with the debtor.” With respect to the claims released in the preceding sentences, the Employee will not initiate or maintain any legal or administrative action or proceeding of any kind against the Company or its predecessors, parent, affiliates, subsidiaries, stockholders, owners, directors, officers, employees, agents, successors, or assigns (including all such persons or entities that have a current or former relationship with the Company), for the purpose of obtaining any personal relief, nor assist or participate in any such proceedings, including any proceedings brought by any third parties (except as otherwise required or permitted by law). The Employee further acknowledges that he/she has been advised by this writing that:

Employee agrees that the release set forth above shall be and remain in effect in all respects as a complete general release as to the matters released.

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