COMMON STOCK PURCHASE WARRANT

Exhibit 99.2

THIS WARRANT HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ 1933 ACT ”), OR ANY APPLICABLE STATE SECURITIES LAWS, AND MAY NOT BE SOLD OR TRANSFERRED UNLESS SUCH SALE OR TRANSFER IS IN ACCORDANCE WITH THE REGISTRATION REQUIREMENTS OF SUCH ACT AND APPLICABLE LAWS OR SOME OTHER EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF SUCH ACT AND APPLICABLE LAWS IS AVAILABLE WITH RESPECT THERETO.

COMMON STOCK PURCHASE WARRANT

H EMOSENSE , I NC .

Effective as of December 6, 2006

Void after December 6, 2013

1. Issuance . This Common Stock Purchase Warrant (the “ Warrant ”) is issued to L IGHTHOUSE C APITAL P ARTNERS IV, L.P. by H EMOSENSE , I NC . , a Delaware corporation (hereinafter with its successors called the “ Company ”).

2. Purchase Price; Number of Shares . The registered holder of this Warrant (the “ Holder ”), commencing on the date hereof, is entitled upon surrender of this Warrant with the subscription form annexed hereto duly executed, at the principal office of the Company, to purchase from the Company, at a price per share of $3.98 (the “ Purchase Price ”), 150,753 fully paid and nonassessable shares of the Company’s Common Stock, $0.001 par value (the “ Common Stock ”).

Until such time as this Warrant is exercised in full or expires, the Purchase Price and the securities issuable upon exercise of this Warrant are subject to adjustment as hereinafter provided. The person or persons in whose name or names any certificate representing shares of Common Stock is issued hereunder shall be deemed to have become the holder of record of the shares represented thereby as at the close of business on the date this Warrant is exercised with respect to such shares, whether or not the transfer books of the Company shall be closed.

3. Payment of Purchase Price . The Purchase Price may be paid (i) in cash or by check, (ii) by the surrender by the Holder to the Company of any promissory notes or other obligations issued by the Company, with all such notes and obligations so surrendered being credited against the Purchase Price in an amount equal to the principal amount thereof plus accrued interest to the date of surrender, or (iii) by any combination of the foregoing.

4. Net Issue Election . The Holder may elect to receive, without the payment by the Holder of any additional consideration, shares of Common Stock equal to the value of this Warrant or any portion hereof by the surrender of this Warrant or such portion to the Company, with the net issue election notice annexed hereto duly executed, at the principal office of the Company. Thereupon, the Company shall issue to the Holder such number of fully paid and nonassessable shares of Common Stock as is computed using the following formula:

1.

X= Y(A-B)

      A

“ Fair Market Value ” of a share of Common Stock as of the date that the net issue election is made (the “ Determination Date ”) shall mean:

(i) If traded on a securities exchange or the Nasdaq National Market, the fair market value of the Common Stock shall be deemed to be the volume-weighted average of the closing or last reported sale prices of the Common Stock on such exchange or market over the ten day period ending ten trading days prior to the Determination Date;

(b) If otherwise traded in an over-the-counter market, the fair market value of the Common Stock shall be deemed to be the average of the closing ask prices of the Common Stock over the five day period ending five trading days prior to the Determination Date; and

(c) If there is no public market for the Common Stock, then fair market value shall be determined in good faith by the Company’s Board of Directors.

5. Partial Exercise . This Warrant may be exercised in part, and the Holder shall be entitled to receive a new warrant, which shall be dated as of the date of this Warrant, covering the number of shares in respect of which this Warrant shall not have been exercised.

6. Fractional Shares . In no event shall any fractional share of Common Stock be issued upon any exercise of this Warrant. If, upon exercise of this Warrant in its entirety, the Holder would, except as provided in this Section 6 , be entitled to receive a fractional share of Common Stock, then the Company shall issue the next higher number of full shares of Common Stock, issuing a full share with respect to such fractional share.

7. Expiration Date; Automatic Exercise. This Warrant shall expire at the close of business on December 6, 2013, and shall be void thereafter (the “ Expiration Date ”). Notwithstanding the foregoing, this Warrant shall automatically be deemed to be exercised in full pursuant to the provisions of Section 4 hereof, without any further action on behalf of the Holder, immediately prior to the time this Warrant would otherwise expire pursuant to the preceding sentence.

8. Reserved Shares; Valid Issuance . The Company covenants that it will at all times from and after the date hereof reserve and keep available such number of its authorized shares of Common Stock free from all preemptive or similar rights therein, as will be sufficient to permit, respectively, the exercise of this Warrant in full. The Company further covenants that such shares as may be issued pursuant to such exercise and/or conversion will, upon issuance, be duly and validly issued, fully paid and nonassessable and free from all taxes, liens and charges with respect to the issuance thereof.

9. Stock Splits and Dividends . If after the date hereof the Company shall subdivide the Common Stock, by split-up or otherwise, or combine the Common Stock, or issue additional shares of Common Stock in

2.

payment of a stock dividend on the Common Stock, the number of shares of Common Stock issuable on the exercise of this Warrant shall forthwith be proportionately increased in the case of a subdivision or stock dividend, or proportionately decreased in the case of a combination, and the Purchase Price shall forthwith be proportionately decreased in the case of a subdivision or stock dividend, or proportionately increased in the case of a combination.

10. Mergers and Reclassifications . If after the date hereof the Company shall enter into any Reorganization (as hereinafter defined), this Warrant shall expire and terminate effective as of the closing of such Reorganization. Notwithstanding the foregoing, in the event that any outstanding warrants to purchase equity securities of the Company are assumed by the successor entity of a Merger (or parent thereof), this Warra