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Exhibit 10.18

FORM OF
thinkorswim Group Inc.
2001 STOCK OPTION PLAN
Notice and Agreement of Grant of Stock Option

TO:              FROM:   Compensation Committee of the Board of Directors       
  DATE:   XXXX

At the direction of the Compensation Committee (the "Committee") of the Board of
Directors of thinkorswim Group Inc. (the "Company"), you are hereby notified
that on XXXX, 20XX (the "Date of Grant") the Committee has granted to you an
option to purchase shares of Common Stock of the Company (the "Option"),
pursuant to the thinkorswim Group Inc. Second Amended and Restated 2001 Stock
Option Plan (the "Plan"), as amended from time to time, which is incorporated
herein by reference and made a part of this agreement. This agreement evidences
the Option that was granted to you. Capitalized terms not otherwise defined
herein shall have the same meanings as in the Plan.

1.This Option is intended to be a Nonstatutory Option.

2.Subject in all respects to the Plan and the terms and conditions set forth
herein and therein, you are hereby granted an Option to purchase from the
Company XXXX shares of Common Stock at the exercise price of $X.XX per share
(the "Option Price"). It is the determination of the Committee that on the Date
of Grant, the Fair Market Value of a share of Common Stock was not more than the
Option Price.

3.The Option may be exercised only by you and, subject to your Continuous
Service, shall become exercisable in installments at a rate of one-fourth (1/4)
of the total number of Shares subject to the Option per year commencing on the
first anniversary of the Date of Grant, and with respect to an additional
one-fourth (1/4) on each anniversary of the Date of Grant thereafter, provided
that your Continuous Service has not terminated with the Employer prior to that
date. If your Continuous Service is terminated for any reason, the Option, to
the extent not exercisable, shall be cancelled without consideration.

4.The Option shall expire on the day prior to the tenth anniversary of the Date
of Grant (the "Expiration Date"). Notwithstanding the foregoing, if your
Continuous Service is terminated prior to the Expiration Date, the vested
portion of the Option shall remain exercisable for the period set forth below:

a.If your Continuous Service is terminated by the Company or its affiliates for
Cause, the Option shall immediately expire on the effective date of the
termination of your Continuous Service;

b.If your Continuous Service is terminated due to your retirement on or after
age 65, the vested portion of the Option shall remain exercisable for a period
of three (3) months following the effective date of the termination of your
Continuous Service;

c.If your Continuous Service is terminated due to your death or total and
permanent disability (within the meaning of Section 422 of the Internal Revenue
Code), the vested portion of the Option shall remain exercisable for a period of
twelve (12) months following the effective date of the termination of your
Continuous Service; and

d.If your Continuous Service is terminated other than due to your death,
disability or retirement on or after age 65, or by the Company or its affiliates
for Cause, the vested

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portion of the Option shall remain exercisable for a period of ten (10) days
following the effective date of the termination of your Continuous Service.

5.The option is nontransferable, other than as may be occasioned by your death,
and then only to your estate or according to the terms of your will or the
provisions of applicable laws of descent and distribution.

In the event that the right to exercise the Option is passed to your estate, or
to a person to whom such right devolves by reason of your death, then the Option
shall be nontransferable in the hands of your executor or administrator or of
such person, except that the Option may be distributed by your executor or
administrator to the distributees of your estate as a part of your estate.

6.Enclosed for your careful review is a copy of the Plan governing the Option,
and a Description of the 2001 Stock Option Plan, otherwise known as the "Plan
Prospectus." At the time or times when you wish to exercise the Option, in whole
or in part, please refer to the provisions of the Plan dealing with methods and
formalities of exercise of the Option. The Company shall have the right, and is
hereby authorized, to withhold from any payment due or transfer made under the
Option, or from any compensation owing to you, applicable withholding taxes, if
any.

Neither the Plan nor this agreement will be construed as giving you the right to
be retained in the employ of the Company or its affiliates, and the Company or
its affiliates may at any time terminate your employment free from any liability
or any claim under the Plan or this agreement, except as otherwise expressly
provided herein.

7.This agreement shall be governed by and construed in accordance with the laws
of Delaware, without regard to the conflicts of laws provisions thereof, and
shall be subject in all respects to the terms of the Plan. If any one or more
provisions of this agreement shall be found to be illegal or unenforceable in
any respect, the validity and enforceability of the remaining provisions hereof
shall not in any way be affected or impaired thereby. This agreement and the
Plan contain the entire agreement between the Company and you relating to the
Option and the other matters set forth herein. This agreement is subject to the
terms and conditions of the Plan. In the event of any inconsistent provisions
between this agreement and the Plan, the Plan shall govern. Except as expressly
provided in this agreement or the Plan with respect to certain actions permitted
to be taken by the Committee with respect to this agreement and the terms of the
Option, this agreement may not be amended, modified, changed, or waived other
than by written instrument signed by the parties hereto. This agreement may be
executed in counterparts, each of which shall be an original with the same
effect as if the signatures were upon the same instrument.

thinkorswim Group Inc. Compensation Committee

   

                                                                              
[Officer]

I hereby acknowledge receipt of a copy of the Plan and the Plan Prospectus,
copies of which are annexed hereto, and represent that I am familiar with the
terms and provisions thereof and hereby accept the Option, subject to all the
terms and provisions of the Plan and this agreement. I hereby

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agree to accept as binding, conclusive and final all decisions or
interpretations of the Compensation Committee with respect to any question
arising under the Plan.

Employee:
 
              

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Date:
 
 
 
        

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Exhibit 10.18

FORM OF thinkorswim Group Inc. 2001 STOCK OPTION PLAN Notice and Agreement of
Grant of Stock Option