EXHIBIT 4.3 NONSTATUTORY STOCK OPTION AGREEMENT

Nonstatutory Stock Option

This Option is not intended to be an incentive stock option under section 422 of the Internal Revenue Code and will be interpreted accordingly.

Vesting

No Shares will vest until you have performed _______ (____) months of Service from the commencement of your employment with the Company. Your Option shall vest as to _______ of the Shares on the date _______ (____) months from the Vesting Start Date as shown on the cover sheet. Thereafter, Shares shall vest at the rate of ________ of the Shares at the end of each full month thereafter. After you have completed ________ (____) months of Service, the number of Shares which vest under this Option at the Exercise Price shall be equal to the product of the number of full months of your continuous employment with the Company (“Service”) (including any approved leaves of absence) from the Vesting Start Date times the number of Shares covered by this Option times ________. The resulting number of Shares will be rounded to the nearest whole number. No additional Shares will vest after your Service has terminated for any reason.

You should note that you may exercise the Option prior to vesting. In that case, the Company has a right to repurchase the unvested shares at the original exercise price if you terminate employment before vesting in all shares you purchased. Also, if you exercise before vesting, you should consider making an 83(b) election. Please see the attached Tax Summary. The 83(b) election must be filed within 30 days of the date you exercise.

Term

Your Option will expire in any event at the close of business at Company headquarters on the day before the tenth anniversary of the Date of Grant, as shown on the cover sheet. (It will expire earlier if your Service terminates, as described below.)

Regular Termination

If your Service terminates for any reason except death, Disability, or for “Cause” your Option will expire at the close of business at Company headquarters on the 30th day after your termination date. During such 30-day period, you may exercise that portion of your Option that was vested on your termination date.

Death

If you die while in Service with the Company, your Option will expire at the close of business at Company headquarters on the date six months after the date of death. During that six-month period, your estate or heirs may exercise that portion of your Option that was vested on your date of death.

Disability

If your Service terminates because of your Disability, your Option will expire at the close of business at Company headquarters on the date six months after your termination date. During that six-month period, you may exercise that portion of your Option that was vested on your date of Disability.

“Disability” means that you are unable to engage in any substantial gainful activity by reason of any medically determinable physical or mental impairment.

Leaves of Absence

For purposes of this Option, your Service does not terminate when you go on a bona fide leave of absence that was approved by the Company in writing, if the terms of the leave provide for continued service crediting, or when continued service crediting is required by applicable law. However, your Service will be treated as terminating 30 days after you went on leave, unless your right to return to work is guaranteed by law or by a contract. Your service terminates in any event when the approved leave ends unless you immediately return to Service. The Company determines which leaves count for this purpose, and when your Service terminates for all purposes under the Plan. The Company also determines the extent to which you may exercise the vested portion of your Option during a leave of absence.

Notice of Exercise

When you wish to exercise this Option, you must execute Exhibit A (and if exercise is prior to vesting you must also execute Exhibits B and D). Your Exercise will be effective when it is received by the Company. If someone else wants to exercise this Option after your death, that person must prove to the Company’s satisfaction that he or she is entitled to do so.

Withholding Taxes

You will not be allowed to exercise this Option unless you make acceptable arrangements to pay any withholding or other taxes that may be due as a result of the Option exercise or the sale of Shares acquired upon exercise of this Option.

By signing this Agreement, you agree not to exercise this Option or sell any Shares acquired upon exercise of this Option at a time when applicable laws, regulations or Company or underwriter trading policies prohibit exercise or sale. In particular, the Company shall have the right to designate one or more periods of time, each of which shall not exceed 180 days in length, during which this Option shall not be exercisable if the Company determines (in its sole discretion) that such limitation on exercise could in any way facilitate a lessening of any restriction on transfer pursuant to the Securities Act or any state securities laws with respect to any issuance of securities by the Company, facilitate the registration or qualification of any securities by the Company under the Securities Act or any state securities laws, or facilitate the perfection of any exemption from the registration or qualification requirements of the Securities Act or any applicable state securities laws for the issuance or transfer of any securities. Such limitation on exercise shall not alter the vesting schedule set forth in this Agreement other than to limit the periods during which this Option shall be exercisable.

Furthermore, in respect of any underwritten public offering by the Company, you agree that you will not sell or otherwise transfer or dispose of any Shares covered by this Option during a reasonable and customary period of time as agreed to by the Company and the underwriters, not to exceed the greater of (a) 180 days following the effective date of the registration statement of the Company filed under the Securities Act in respect of such offering and (b) such other period of time as agreed to by holders of a majority of the then outstanding Shares. By signing this Agreement you agree to execute and deliver such other agreements as may be reasonably requested by the Company or the underwriter which are consistent with the foregoing or which are necessary to give further effect thereto. The Company may impose stop-transfer instructions with respect to the Shares subject to the foregoing restriction until the end of such period.

If the sale of Shares under the Plan is not registered under the Securities Act of 1933, as amended (the “Securities Act”), but an exemption is available which requires an investment or other representation, you shall represent and agree at the time of exercise that the Shares being acquired upon exercise of this Option are being acquired for investment, and not with a view to the sale or distribution thereof, and shall make such other representations as are deemed necessary or appropriate by the Company and its counsel. 

In the event that you propose to sell, pledge or otherwise transfer to a third party any Shares acquired under this Agreement, or any interest in such Shares, the Company shall have the “Right of First Refusal” with respect to all (and not less than all) of such Shares. If you desire to transfer Shares acquired under this Agreement, you must give a written “Transfer Notice” to the Company describing fully the proposed transfer, including the number of Shares proposed to be transferred, the proposed transfer price and the name and address of the proposed transferee. The Transfer Notice shall be signed both by you and by the proposed transferee and must constitute a binding commitment of both parties to the transfer of the Shares.

The Company and its assignees shall have the right to purchase all, and not less than all, of the Shares on the terms described in the Transfer Notice (subject, however, to any change in such terms permitted in the next paragraph) by delivery of a notice of exercise of the Right of First Refusal within 30 days after the date when the Transfer Notice was received by the Company.

The Company’s rights under this Subsection shall be freely assignable, in whole or in part.

If the Company fails to exercise its Right of First Refusal within 30 days after the date when it received the Transfer Notice, you may, not later than 60 days following receipt of the Transfer Notice by the Company, conclude a transfer of the Shares subject to the Transfer Notice on the terms and conditions described in the Transfer Notice. Any proposed transfer on terms and conditions different from those described in the Transfer Notice, as well as any subsequent proposed transfer by you, shall again be subject to the Right of First Refusal and shall require compliance with the procedure described in the paragraph above. If the Company exercises its Right of First Refusal, you and the Company (or its assignees) shall consummate the sale of the Shares on the terms set forth in the Transfer Notice.

The Company’s Right of First Refusal shall inure to the benefit of its successors and assigns and shall be binding upon any transferee of the Shares.