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

OMB APPROVAL OMB Number: 3235-0287 Expires: January 31, 2005 Estimated average burden hours per response... 0.5

(Print or Type Responses)

1. Name and Address of Reporting Person * Valentin Gapontsev Trust I   2. Issuer Name and Ticker or Trading Symbol IPG PHOTONICS CORP [IPGP] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director __X__ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O IPG PHOTONICS CORPORATION, 50 OLD WEBSTER ROAD 3. Date of Earliest Transaction (Month/Day/Year) 12/02/2011 (Street) OXFORD, MA 01540 4. If Amendment, Date 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 (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 12/02/2011   S   2,261 D $ 41.44 (1) 7,997,739 D (3)   Common Stock 12/05/2011   S   28,859 D $ 41.29 (2) 7,968,880 D (3)   Common Stock 12/06/2011   S   38,880 D $ 39.95 7,930,000 D (3)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
	Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.		SEC 1474 (9-02)

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

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Valentin Gapontsev Trust I C/O IPG PHOTONICS CORPORATION 50 OLD WEBSTER ROAD OXFORD, MA 01540		X
Shcherbakov Eugene A C/O IPG PHOTONICS CORPORATION 50 OLD WEBSTER ROAD OXFORD, MA 01540	X	X	Managing Director of IPG Laser
PLATONOV NIKOLAI C/O IPG PHOTONICS CORPORATION 50 OLD WEBSTER ROAD OXFORD, MA 01540		X

Signatures

/s/ Angelo P. Lopresti, Attorney-in-fact for Valentin Gapontsev Trust I		12/06/2011
**Signature of Reporting Person		Date
/s/ Angelo P. Lopresti, Attorney-in-fact for N. Platonov		12/06/2011
**Signature of Reporting Person		Date
/s/ Angelo P. Lopresti, Attorney-in-fact for E. Scherbakov		12/06/2011
**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)	The reported transaction involved sales transactions from $41.25 to $41.74 per share. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer information regarding the number of shares sold at each separate price.
(2)	The reported transaction involved sales transactions from $40.68 to $41.72 per share. The Reporting Person undertakes to provide upon request by the SEC staff, the Issuer or a security holder of the Issuer information regarding the number of shares sold at each separate price.
(3)	These shares are owned directly by the Valentin Gapontsev Trust I (Gapontsev Trust I), and indirectly by (i) Nikolai Platonov, a trustee of Gapontsev Trust I, and (iv) Eugene Scherbakov, a trustee of Gapontsev Trust I. On May 20, 2011, Eugene Scherbakov was appointed as a trustee of the Gapontsev Trust I. Drs. Platonov and Scherbakov each disclaim ownership of the securities directly owned by Gapontsev Trust I except to the extent of his pecuniary interest therein, and the inclusion of thee shares in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 of the Securities Exchange Act of 1034, as amended, or for any other purpose.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.