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, 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 *   TA ADVENT VIII LP 2. Date of Event Requiring Statement (Month/Day/Year) 12/12/2006 3. Issuer Name and Ticker or Trading Symbol IPG PHOTONICS CORP [IPGP] (Last) (First) (Middle) JOHN HANCOCK TOWER, 200 CLARENDON ST, 56TH FLOOR 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) 5. If Amendment, Date Original Filed(Month/Day/Year) (Street) BOSTON, MA 02116 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 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)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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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 of Derivative Security: 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
Series B Preferred Stock	12/12/2006	  (3)	Common Stock	354,767	$ (1)	D	Â
Series B Warrants	12/12/2006	04/01/2008	Common Stock	(2)	$ (2)	D	Â

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
TA ADVENT VIII LP JOHN HANCOCK TOWER 200 CLARENDON ST, 56TH FLOOR BOSTON, MA 02116	  X	Â	Â	Â

Signatures

TA/Advent VIII L.P.		12/12/2006
**Signature of Reporting Person		Date
By: TA Associates VIII LLC, its General Partner		12/12/2006
**Signature of Reporting Person		Date
By: TA Associates, Inc., its Manager		12/12/2006
**Signature of Reporting Person		Date
By: Thomas P. Alber, Chief Financial Officer		12/12/2006
**Signature of Reporting Person		Date

Explanation of Responses:

*	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).
(1)	The number of shares of Common Stock is subject to adjustment based upon the initial public offering price in connection with the issuer's initial public offering.
(2)	The number of shares of Common Stock underlying the warrants is indeterminate and will be determined based upon the initial public offering price of the Common Stock in connection with the issuer's initial public offering.
(3)	N/A
  Remarks: The Reporting Person has a representative on the issuer's board of directors.  Michael Child currently serves as the Reporting Person's representative on the board of directors and the Reporting Person is deemed a director of the issuer by deputization.

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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