Exhibit 10.A

RESTRICTED STOCK UNIT AGREEMENT UNDER THE

2003 LONG-TERM INCENTIVE PLAN AS AMENDED

THIS AGREEMENT is made as of the      day of                     , 20     by and
between Sigma-Aldrich Corporation (“Company”) and                     
(“Awardee”).

WHEREAS, the Board of Directors of the Company (“Board of Directors”) has
adopted and the shareholders of the Company have approved the 2003 Long-Term
Incentive Plan, as amended (“Plan”) pursuant to which Other Stock-Based Awards,
including Awards pursuant to which common stock of the Company (“Common Stock”)
may be acquired by employees of the Company and its subsidiaries in the future;
and

WHEREAS, the Company desires to make a restricted stock unit award to the
Awardee of                      (            ) restricted stock units under the
terms hereinafter set forth:

NOW, THEREFORE, in consideration of the premises, and of the mutual agreements
hereinafter set forth, it is covenanted and agreed as follows:

1. Award Subject to Plan. This award is made under, and is expressly subject to,
all the terms and provisions of the Plan, a copy of which has been given to
Awardee and which terms are incorporated herein by reference.

2. Terms of Award. Pursuant to action of the Compensation Committee of the Board
of Directors, which action was made effective on                     , 20    
(“Date of Award”), the Company awards to the Awardee                     
(            ) restricted stock units (“Restricted Stock Units”), subject to the
terms, conditions, and adjustments set forth in this Restricted Stock Unit
Agreement (“Agreement”) and the Plan. Each Restricted Stock Unit represents the
right to receive one share of the Common Stock of the Company (“Share”) to be
issued and delivered at the end of the Vesting Period, subject to the risk of
forfeiture described herein. The Restricted Stock Units are subject to
forfeiture and cancellation without payment therefore for a period commencing on
the Date of Award and ending on February 1, 2013 (“Vesting Period”), in the
event the following occurs:

 

  a. if the Awardee’s employment with the Company terminates during the Vesting
Period for any reason other than an involuntary termination of the Awardee’s
employment by the Company without Cause (as defined in the Plan), death or
Disability (as defined in the Plan) or following a Change of Control, or

 

  b. The Board of Directors of the Company determines the Awardee engaged in
intentional conduct that caused or substantially caused the Company to restate
the Company’s financial statements as filed with the Securities and Exchange
Commission.

In the event either of the foregoing forfeiture triggers shall occur, the
Restricted Stock Units shall not vest and shall become forfeited for no value
and without any issuance of Shares. If neither of the above described forfeiture
triggers occurs during the Vesting Period, the Restricted Stock Units shall
become fully vested and the Shares underlying such Restricted Stock Units will
be automatically issued and delivered on the last day of the Vesting Period,
provided that the Awardee remains employed with the Company through such date.

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3. Effect of Change of Control or Termination without Cause, Disability or
Death. In the event of the Awardee’s termination of employment on account of an
involuntary termination of employment by the Company without Cause, death, or
Disability while employed with the Company during the Vesting Period, a pro rata
portion of all of the Restricted Stock Units described in Section 2 above shall
vest, and the Shares underlying such Restricted Stock Units will be
automatically issued and delivered on the date of such termination of
employment. Such prorated amount shall be based on the number of months in the
Vesting Period during which the Awardee is employed with the Company, and the
Awardee shall be deemed to be employed for an entire month if the Awardee is so
involuntarily terminated, dies or suffers a Disability during such month while
employed during the Vesting Period. Upon the occurrence of a Change in Control
while the Awardee is employed with the Company during the Vesting Period, all of
the Restricted Stock Units described in Section 2 above shall vest, and the
Shares underlying such Restricted Stock Units will be automatically issued and
delivered on the earlier of the Awardee’s termination of employment with the
Company or the last day of the Vesting Period.

4. No Shareholder Rights. No rights of a shareholder shall exist with respect to
the Restricted Stock Units as a result of the mere grant of the Restricted Stock
Units. Such rights shall exist only after issuance of the Shares. Without
limiting the foregoing, the Awardee shall not be entitled to receive, currently
or on a deferred basis, any payments equivalent to cash, stock or other property
paid by the Company as dividends on the Company’s common stock prior to the
issuance of the Shares.

5. Withholding. The Awardee is responsible for any taxes required to be withheld
under Federal, state, or local law in connection with the vesting of the
Restricted Stock Units, the issuance and delivery of Shares to the Awardee, or
any other event occurring pursuant to this Restricted Stock Unit Agreement or
the Plan. The Company shall withhold from any payment hereunder an amount of
Shares sufficient to cover any required withholding taxes due at the time such
Shares are otherwise due to be issued and delivered hereunder to the extent
required by minimum statutory withholding requirements.

6. Clawback. In the event the Board of Directors of the Company determines that
the Awardee engaged in intentional conduct for the period commencing on
February 1, 2013 and for two years thereafter ending January 31, 2015 and such
conduct caused or substantially caused the Company to restate the Company’s
financial statements as filed with the Securities and Exchange Commission, then
the Awardee shall pay to the Company the amount equal to the difference of the
value of the Shares as awarded on February 1, 2013 less any personal income
taxes paid thereon.

7. Definitions; Copy of Plan. To the extent not specifically defined in this
Agreement all capitalized terms used in this Agreement will have the same
meanings ascribed to them in the Plan. By execution of this Agreement, the
Awardee acknowledges receipt of a copy of the Plan.

8. Board Administration. This award has been made pursuant to a determination
made by the Compensation Committee of the Board of Directors, and such Committee
or any successor or substitute authorized in accordance with the Plan, and
subject to the express terms of this Agreement, shall have plenary authority to
interpret any provision of this Agreement and to make any determinations
necessary or advisable for the administration of this Agreement and may waive or
amend any provisions hereof in accordance with the Plan.

9. Amendment. This Agreement may be amended, in whole or in part, at any time by
the Compensation Committee in accordance with the Plan.

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10. Non-Transferability. This Restricted Stock Unit Award may not be assigned,
transferred, or in any way encumbered except by will or the laws of descent and
distribution.

11. Section 409A. It is intended that this Agreement shall be administered in a
manner that will comply with or meet an exception from Section 409A of the Code,
and this Agreement shall be administered and interpreted in accordance with such
intent. The Committee may adopt rules deemed necessary or appropriate to qualify
for an exception from or to comply with the requirements of Section 409A of the
Code. Notwithstanding anything in this Section to the contrary, no amendment to
or payment under this Agreement will be made unless permitted under Section 409A
of the Code. If any amount shall be payable hereunder as a result of the
Awardee’s “separation from service” at such time as the Awardee is a “specified
employee” (as those terms are defined for purposes of Section 409A of the Code)
and such amount is subject to the provisions of Section 409A of the Code, then
no payment shall be made, except as permitted under Section 409A of the Code,
prior to the first day of the seventh calendar month beginning after the
Awardee’s separation from service, provided that, payment shall be made sooner
upon the date of the Awardee’s earlier death following such separation from
service.

IN WITNESS WHEREOF, the Company has caused this Agreement to be executed on its
behalf, and the Awardee has signed this Agreement to evidence the Awardee’s
acceptance of the terms hereof, all as of the date first above written.

 

SIGMA-ALDRICH CORPORATION By:  

 

Name:   Title: