Change of Control Agreement

CHANGE OF CONTROL AGREEMENT


This Change of Control Agreement (the "Agreement") is made and entered into effective as of January 19, 2000, by and between Wendy R. Hitchcock (the "Employee") and ACLARA BioSciences, Inc., a Delaware corporation (the "Company").


RECITALS


A. It is expected that another company or other entity may from time to time consider the possibility of acquiring the Company or that a change in control may otherwise occur, with or without the approval of the Company's Board of Directors (the "Board"). The Board recognizes that such consideration can be a distraction to the Employee, an executive officer of the Company, and can cause the Employee to consider alternative employment opportunities. The Board has determined that it is in the best interests of the Company and its stockholders to assure that the Company will have the continued dedication and objectivity of the Employee, notwithstanding the possibility, threat or occurrence of a Change of Control (as defined below) of the Company.


B. The Board believes that it is in the best interests of the Company and its stockholders to provide the Employee with an incentive to continue his or her employment with the Company.


C. The Board believes that it is imperative to provide the Employee with certain benefits upon termination of the Employee's employment in connection with a Change of Control, which benefits are intended to provide the Employee with sufficient security to encourage the Employee to remain with the Company notwithstanding the possibility of a Change of Control.


D. To accomplish the foregoing objectives, the Board of Directors has directed the Company, upon execution of this Agreement by the Employee, to agree to the terms provided in this Agreement.


E. Certain capitalized terms used in the Agreement are defined in Section 3 below.


In consideration of the mutual covenants contained in this Agreement, and in consideration of the continuing employment of Employee by the Company, the parties agree as follows:


1. 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, including (without limitation) any termination prior to a Change of Control, the Employee shall not be entitled to any payments or benefits, other than as provided by this Agreement, or as may otherwise be available in accordance with the terms of the Company's then existing employee plans and written policies in effect at the time of termination. The terms of this Agreement shall terminate upon the earlier of


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(i) the date on which Employee ceases to be employed as an executive officer of the Company, other than as a result of an involuntary termination by the Company without Cause (ii) the date that all obligations of the parties hereunder have been satisfied, or (iii) one (1) year after a Change of Control. A termination of the terms of this Agreement pursuant to the preceding sentence shall be effective for all purposes, except that such termination shall not affect the payment or provision of compensation or benefits on account of a termination of employment occurring prior to the termination of the terms of this Agreement.


2. Stock Options. Subject to Sections 4 and 5 below, in the event of an Involuntary Termination of Employee's employment with the Company within one year following a Change of Control, each stock option granted for the Company's securities held by the Employee shall become fully vested and immediately exercisable on the effective date of the Involuntary Termination and shall be exercisable to the extent so vested in accordance with the provisions of the stock option agreement and stock option plan pursuant to which such stock option was granted.


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


(a) Change of Control. "Change of Control" shall mean the occurrence of any of the following events:


(i) Ownership. Any "Person" (as such term is used in Sections 13(d) and 14(d) of the Securities Exchange Act of 1934, as amended) is or becomes the "Beneficial Owner" (as defined in Rule 13d-3 under said Act), directly or indirectly, of securities of the Company representing twenty percent (20%) or more of the total voting power represented by the Company's then outstanding voting securities without the approval of the Board of Directors of the Company; or


(ii) Merger/Sale of Assets. A merger or consolidation of the Company whether or not approved by the Board of Directors of the Company, 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 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, or the stockholders of the Company ap ...