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* McMahon Arthur (Last) (First) (Middle) C/O SYNTA PHARMACEUTICALS CORP. 45 HARTWELL AVENUE (Street) LEXINGTON MA 02421 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 01/03/2014	3. Issuer Name and Ticker or Trading Symbol SYNTA PHARMACEUTICALS CORP [ SNTA ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director 10% Owner X Officer (give title below) Other (specify below) SVP, People Operations	5. If Amendment, Date of 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

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)
Common Stock	12,829	D

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
Employee Stock Option (Right to Buy)	(1)	02/06/2017	Common Stock	25,000	$10	D
Employee Stock Option (Right to Buy)	(1)	02/26/2017	Common Stock	10,000	$8.75	D
Employee Stock Option (Right to Buy)	(1)	02/27/2018	Common Stock	22,680	$8.82	D
Employee Stock Option (Right to Buy)	(1)	04/13/2019	Common Stock	24,948	$2.49	D
Employee Stock Option (Right to Buy)	(2)	03/01/2020	Common Stock	30,888	$4.02	D
Employee stock Option (Right to Buy)	(3)	03/01/2021	Common Stock	33,904	$5.26	D
Employee Stock Option (Right to Buy)	(4)	03/06/2022	Common Stock	40,848	$4.22	D
Employee Stock Option (Right to Buy)	(5)	09/13/2022	Common Stock	15,000	$8.05	D
Employee Stock Option (Right to Buy)	(6)	03/05/2023	Common Stock	44,312	$9.65	D

Explanation of Responses:

1. The option is fully vested and exercisable.

2. The option vested as to 25% of the shares on March 1, 2011 and as to an additional 6.25% of the shares each quarter thereafter.

3. The option vested as to 25% of the shares on March 1, 2012 and as to an additional 6.25% of the shares each quarter thereafter.

4. The option vested as to 25% of the shares on March 6, 2013 and as to an additional 6.25% of the shares each quarter thereafter.

5. The option vested as to 25% of the shares on September 13, 2013 and as to an additional 6.25% of the shares each quarter thereafter.

6. The option vests as to 25% of the shares on March 5, 2014 and as to an additional 6.25% of the shares each quarter thereafter

	/s/ Garrett Winslow, Attorney-in-Fact	01/13/2014
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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