Exhibit 10.4

ALIGN TECHNOLOGY, INC.

2005 INCENTIVE PLAN

STOCK OPTION AWARD AGREEMENT

Unless otherwise defined herein, the terms defined in the 2005 Incentive Plan (the “Plan”) will have the same defined meanings in this Award Agreement.

I.                                         AGREEMENT

A.                                   Grant of Option.

The Administrator hereby grants to individual named in the Notice of Grant attached to or otherwise provided contemporaneously with this Agreement (the “Participant”) an option (the “Option”) to purchase the number of Shares, as set forth in the Notice of Grant, at the exercise price per share set forth in the Notice of Grant (the “Exercise Price”), subject to the terms and conditions of the Plan, which is incorporated herein by reference.  Subject to Section 21(c) of the Plan, in the event of a conflict between the terms and conditions of the Plan and the terms and conditions of this Award Agreement, the terms and conditions of the Plan will prevail.

If designated in the Notice of Grant as an Incentive Stock Option (“ISO”), this Option is intended to qualify as an Incentive Stock Option under Section 422 of the Code.  However, if this Option is intended to be an Incentive Stock Option, to the extent that it exceeds the $100,000 rule of Code Section 422(d) it will be treated as a Nonstatutory Stock Option (“NSO”).

B.                                     Exercise of Option.

(a)                                  Right to Exercise.  This Option is exercisable during its term in accordance with the Vesting Schedule set out in the Notice of Grant and the applicable provisions of the Plan and this Award Agreement.

(b)                                 Method of Exercise.  This Option is exercisable by delivery of an exercise notice, in the form attached as Exhibit A or by electronic delivery in the manner established by the Company’s stock option administrator (the “Exercise Notice”) or in such other form and manner as determined by the Administrator, which will state the election to exercise the Option, the number of Shares in respect of which the Option is being exercised (the “Exercised Shares”), and such other representations and agreements as may be required by the Company pursuant to the provisions of the Plan.  The Exercise Notice will be completed by Participant and delivered to the Company.  The Exercise Notice will be accompanied by payment of the aggregate Exercise Price as to all Exercised Shares together with any applicable withholding taxes.  This Option will be deemed to be exercised upon receipt by the Company of such properly completed Exercise Notice accompanied by such aggregate Exercise Price.

No Shares will be issued pursuant to the exercise of this Option unless such issuance and exercise comply with Applicable Laws.  Assuming such compliance, for income tax purposes the Exercised Shares will be considered transferred to Participant on the date the Option is exercised with respect to such Exercised Shares.

C.                                     Method of Payment.

Payment of the aggregate Exercise Price will be by any of the following, or a combination thereof, at the election of Participant:

1.                                  cash;

2.                                  check;

3.                                  consideration received by the Company under a formal cashless exercise program adopted by the Company in connection with the Plan; or

4.                                  surrender of other Shares which, (i) in the case of Shares acquired from the Company, either directly or indirectly, have been owned by the Participant and not subject to a substantial risk of forfeiture for more than six (6) months on the date of surrender, and (ii) have a Fair Market Value on the date of surrender equal to the aggregate Exercise Price of the Exercised Shares.

D.                                    Non-Transferability of Option.

This Option may not be transferred in any manner otherwise than by will or by the laws of descent or distribution and may be exercised during the lifetime of Participant only by Participant.

E.                                      Term of Option.

This Option may be exercised only within the term set out in the Notice of Grant, and may be exercised during such term only in accordance with the Plan and the terms of this Award Agreement.

F.                                      Tax Obligations.  

1.                                  Withholding Taxes.  Participant agrees to make appropriate arrangements with the Company (or the Parent or Subsidiary employing or retaining Participant) for the satisfaction of all Federal, state, and local income and employment tax withholding requirements applicable to the Option exercise.  Participant acknowledges and agrees that the Company may refuse to honor the exercise and refuse to deliver Shares if such withholding amounts are not delivered at the time of exercise.

2.                                  Notice of Disqualifying Disposition of ISO Shares.  If the Option granted to Participant herein is an ISO, and if Participant sells or otherwise disposes of any of the Shares acquired pursuant to the ISO on or before the later of (1) the date two years after the Grant Date, or (2) the date one year after the date of exercise, Participant will immediately notify the Company in writing of such disposition.  Participant agrees that Participant may be subject to income tax withholding by the Company on the compensation income recognized by Participant.

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G.                                     Entire Agreement; Governing Law.

Each of the Plan and Notice of Grant is incorporated herein by reference.  The Plan, the Notice of Grant and this Award Agreement constitute the entire agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and Participant with respect to the subject matter hereof, and may not be modified adversely to Participant’s interest except by means of a writing signed by the Company and Participant.  This Award Agreement is governed by the internal substantive laws, but not the choice of law rules, of California.

H.                                    NO GUARANTEE OF CONTINUED SERVICE.

PARTICIPANT ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO THE VESTING SCHEDULE HEREOF IS EARNED ONLY BY CONTINUING AS AN EMPLOYEE, CONSULTANT OR NON-EMPLOYEE DIRECTOR AT THE WILL OF THE COMPANY (AND NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED AN OPTION OR PURCHASING SHARES HEREUNDER).  PARTICIPANT FURTHER ACKNOWLEDGES AND AGREES THAT THIS AGREEMENT, THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET FORTH IN THE NOTICE OF GRANT DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT AS AN EMPLOYEE, CONSULTANT OR NON-EMPLOYEE DIRECTOR FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL, AND WILL NOT INTERFERE WITH PARTICIPANT’S RIGHT OR THE COMPANY’S RIGHT TO TERMINATE PARTICIPANT’S RELATIONSHIP AS AN EMPLOYEE, CONSULTANT OR NON-EMPLOYEE DIRECTOR AT ANY TIME, WITH OR WITHOUT CAUSE.

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By acknowledging and accepting the Plan, the Plan Prospectus, the Notice of Grant and this Award Agreement in accordance with the procedures established by the Company, Participant agrees that this Option is granted under and governed by the terms and conditions of the Plan, the Notice of Grant and this Award Agreement.  Participant has reviewed the Plan, the Notice of Grant and this Award Agreement in their entirety, has had an opportunity to obtain the advice of counsel prior to executing this Award Agreement and fully understands all provisions of the Plan, the Notice of Grant and Award Agreement.  Participant hereby agrees to accept as binding, conclusive and final all decisions or interpretations of the Administrator upon any questions relating to the Plan, the Notice of Grant and Award Agreement.  Participant further agrees to notify the Company upon any change in the residence address.

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EXHIBIT A

ALIGN TECHNOLOGY, INC.

2005 INCENTIVE PLAN

EXERCISE NOTICE

Align Technology, Inc.

881 Martin Avenue

Santa Clara, CA

95050

Attention:  Stock Option Administrator

1.                                       Exercise of Option.  Effective as of today,                                        ,         , the undersigned (“Purchaser”) hereby elects to purchase                          shares (the “Shares”) of the Common Stock of Align Technology, Inc. (the “Company”) under and pursuant to the 2005 Incentive Plan (the “Plan”) and the Award Agreement dated                  (the “Award Agreement”).  The purchase price for the Shares will be $                        , as required by the Award Agreement.

2.                                       Delivery of Payment.  Purchaser herewith delivers to the Company the full purchase price for the Shares and any required withholding taxes to be paid in connection with the exercise of the Option.

3.                                       Representations of Purchaser.  Purchaser acknowledges that Purchaser has received, read and understood the Plan and the Award Agreement and agrees to abide by and be bound by their terms and conditions.

4.                                       Rights as Stockholder.  Until the issuance (as evidenced by the appropriate entry on the books of the Company or of a duly authorized transfer agent of the Company) of the Shares, no right to vote or receive dividends or any other rights as a stockholder will exist with respect to the Optioned Stock, notwithstanding the exercise of the Option.  The Shares so acquired will be issued to Participant as soon as practicable after exercise of the Option.  No adjustment will be made for a dividend or other right for which the record date is prior to the date of issance, except as provided in Section 16 of the Plan.

5.                                       Tax Consultation.  Purchaser understands that Purchaser may suffer adverse tax consequences as a result of Purchaser’s purchase or disposition of the Shares.  Purchaser represents that Purchaser has consulted with any tax consultants Purchaser deems advisable in connection with the purchase or disposition of the Shares and that Purchaser is not relying on the Company for any tax advice.

6.                                       Entire Agreement; Governing Law.  The Plan and Award Agreement are incorporated herein by reference.  This Agreement, the Plan and the Award Agreement constitute the entire

agreement of the parties with respect to the subject matter hereof and supersede in their entirety all prior undertakings and agreements of the Company and Purchaser with respect to the subject matter hereof, and may not be modified adversely to the Purchaser’s interest except by means of a writing signed by the Company and Purchaser.  This agreement is governed by the internal substantive laws, but not the choice of law rules, of California.

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