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

QuickLinks -- Click here to rapidly navigate through this document

Exhibit 10.18

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

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 to