SEC Form 3

FORM 3

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

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1. Name and Address of Reporting Person* Serenity Investments, LLC (Last) (First) (Middle) 830 NORTH BLVD (Street) OAK PARK IL 60301 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 07/01/2013	3. Issuer Name and Ticker or Trading Symbol KCG Holdings, Inc. [ KCG ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)	5. If Amendment, Date of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Class A Common Stock, par value $0.01 per share	13,743,517	D(1)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Class A Warrants	07/01/2013	07/01/2017	Class A Common Stock	1,570,983	$12	D(1)
Class B Warrants	07/01/2013	07/01/2018	Class A Common Stock	1,570,983	$13.5	D(1)
Class C Warrants	07/01/2013	07/01/2019	Class A Common Stock	1,570,983	$15	D(1)

1. Name and Address of Reporting Person* Serenity Investments, LLC (Last) (First) (Middle) 830 NORTH BLVD (Street) OAK PARK IL 60301 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Schuler Mary Jo (Last) (First) (Middle) C/O SERENITY INVESTMENTS, LLC 830 NORTH BLVD (Street) OAK PARK IL 60301 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. All of the shares of Class A Common Stock and the Class A Warrants, Class B Warrants and Class C Warrants reported on this Form 3 are held directly by Serenity Investments, LLC, a limited liability company organized under the laws of the state of Alaska ("Serenity"), and indirectly by Mary Jo Schuler. Mary Jo Schuler and her husband, Stephen G. Schuler, separately hold equity interests in Serenity that together represent a controlling equity interest in Serenity. Mary Jo Schuler disclaims beneficial ownership of these securities, except to the extent of her pecuniary interest therein.

Remarks:

Exhibit List: Exhibit 24(i)--Power of Attorney for Serenity Investments, LLC Exhibit 24(ii)--Power of Attorney for Mary Jo Schuler

	/s/ Stephen G. Schuler, by power of attorney for Serenity Investments, LLC	07/03/2013
	/s/ Stephen G. Schuler, by power of attorney for Mary Jo Schuler	07/03/2013
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (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).
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