FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * Santori Peter   2. Issuer Name and Ticker or Trading Symbol THINKORSWIM GROUP INC. [SWIM] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chief Legal Officer (Last) (First) (Middle) 600 WEST CHICAGO AVE., SUITE 100 3. Date of Earliest Transaction (Month/Day/Year) 06/11/2009 (Street) CHICAGO, IL 60610 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 06/11/2009   D   18,850 (4) (5) D (4) (5) 0 D

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Stock Options

$ 8.11

06/11/2009

D

15,000

(1)(3)

05/19/2018

Common Stock

15,000

(2)

0

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Santori Peter 600 WEST CHICAGO AVE., SUITE 100 CHICAGO, IL 60610			Chief Legal Officer

Signatures

/s/ Peter Santori		06/11/2009
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Options were exercisable in four equal installments beginning one year from date of grant. Grant date was 05/19/08.
(2)	Per Instruction 4 (c)(iii), this column is to be left blank.
(3)	Pursuant to the terms of the offer to exchange, filed as an exhibit to a Schedule TO on April 17, 2009, as amended (the "Offer to Exchange"), the reporting person elected to tender all options with an exercise price equal to or greater than $10.50, the threshold exercise price, as described in the Offer to Exchange. As described in the Offer to Exchange, the conversion ratios of options tendered to restricted stock units were as follows: Exercise Price Option to RSU Exchange Ratio: $9.00 -to- $10.852.0 -to- 1 $12.92 -to- $14.73 2.4 -to- 1 $15.69 -to- $16.92 2.7 -to- 1 $23.54 3.7 -to- 1 $25.45 -to- $38.95 10.0 -to- 1All outstanding options and/or RSUs were then assumed by TD AMERITRADE pursuant to the Merger Agreement.
(4)	Disposed of pursuant to the terms of the Agreement and Plan of Merger dated as of January 8, 2009 (the "Merger Agreement"), by and among TD AMERITRADE Holding Corporation, a Delaware corporation ("TD AMERITRADE"), Tango Acquisition Corporation One, a Delaware corporation and a direct, wholly-owned subsidiary of TD AMERITRADE, Tango Acquisition Corporation Two, a Delaware corporation and a direct, wholly-owned subsidiary of TD AMERITRADE, and the Issuer. Shares of Common Stock of the Issuer held outright (i.e., not subject to restrictions or which does not cease to be subject to restrictions as of the closing of the transactions contemplated by the Merger Agreement) shall be cancelled in exchange for $3.34 in cash, without interest and less any applicable withholding, and 0.3980 of a share of TD AMERITRADE common stock, which had a volume-weighted exercise price on the day prior to the date of closing equal to $17.99.
(5)	Shares of Common Stock of the Issuer that continue to be subject to restrictions immediately following the closing of the transactions contemplated by the Merger Agreement were assumed by TD AMERITRADE pursuant to the Merger Agreement and will be settled in shares of common stock of TD AMERITRADE upon vesting. The reporting person has 11,350 shares of Common Stock of the Issuer that will remain subject to restrictions following the closing of the transactions contemplated by the Merger Agreement and which were thus assumed by TD AMERITRADE.

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