Ownership Submission
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 *
NBGE Manager, LLC
  2. Issuer Name and Ticker or Trading Symbol
Proto Labs Inc [PRLB]
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 NORTH BRIDGE GROWTH EQUITY, 950 WINTER STREET, SUITE 4600
3. Date of Earliest Transaction (Month/Day/Year)
08/22/2012
(Street)

WALTHAM, MA 02454
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 08/22/2012   J(1)   1,600,000 D $ 0 4,821,790 I By North Bridge Growth Equity I, L.P. (2)
Common Stock               1,126 D (3)  
Common Stock               610 D (4)  
Common Stock               585 I By Angel 2011 Dynasty Trust (5)

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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

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
NBGE Manager, LLC
C/O NORTH BRIDGE GROWTH EQUITY
950 WINTER STREET, SUITE 4600
WALTHAM, MA 02454
    X    
NBGE GP, LLC
C/O NORTH BRIDGE GROWTH EQUITY
950 WINTER STREET, SUITE 4600
WALTHAM, MA 02454
    X    
NORTH BRIDGE GROWTH EQUITY I LP
C/O NORTH BRIDGE GROWTH EQUITY
950 WINTER STREET, SUITE 4600
WALTHAM, MA 02454
    X    
North Bridge Growth Management, L.P.
C/O NORTH BRIDGE GROWTH EQUITY
950 WINTER STREET, SUITE 4600
WALTHAM, MA 02454
    X    
ANDERSON EDWARD T
C/O NORTH BRIDGE GROWTH EQUITY
950 WINTER STREET, SUITE 4600
WALTHAM, MA 02454
    X    
DAMORE RICHARD A
C/O NORTH BRIDGE GROWTH EQUITY
950 WINTER STREET, SUITE 4600
WALTHAM, MA 02454
    X    

Signatures

 /s/ Julie M. Regnier, Attorney-in-Fact for NBGE Manager, LLC   08/24/2012
**Signature of Reporting Person Date

 Julie M. Regnier, Attorney-in-Fact for NBGE GP, LLC   08/24/2012
**Signature of Reporting Person Date

 Julie M. Regnier, Attorney-in-Fact for North Bridge Growth Equity I, L.P.   08/24/2012
**Signature of Reporting Person Date

 Julie M. Regnier, Attorney-in-Fact for North Bridge Growth Management, L.P.   08/24/2012
**Signature of Reporting Person Date

 Julie M. Regnier, Attorney-in-Fact for Edward Anderson   08/24/2012
**Signature of Reporting Person Date

 Julie M. Regnier, Attorney-in-Fact for Richard D'Amore   08/24/2012
**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 transaction reported on this Form 4 represents a pro rata distribution, and not a purchase or sale of securities, by North Bridge Growth Equity I, L.P. to its general and limited partners without consideration.
(2) Represents shares held directly by North Bridge Growth Equity I, L.P. NBGE Manager, LLC ("NBGE") is the managing manager of NBGE GP, LLC, which is the sole general partner of North Bridge Growth Management, L.P., which is the sole general partner of North Bridge Growth Equity I, L.P. NBGE has sole vesting and dispositive power over such shares. Shared voting and investment power over such shares is vested in the managers of NBGE, Edward Anderson and Richard D'Amore. Mr. Anderson and Mr. D'Amore each disclaim any beneficial ownership of such shares, except to the extent of any pecuniary interest therein. This report shall not be deemed an admission that any of the reporting persons is the beneficial owner of such securities for purposes of Section 16 or for any other purpose.
(3) Represents shares held of record by Mr. Anderson received in connection with the pro rata distribution from North Bridge Growth Equity I, L.P. referenced in footnote 1 above.
(4) Represents shares held of record by Mr. D'Amore received in connection with the pro rata distribution from North Bridge Growth Equity I, L.P. referenced in footnote 1 above.
(5) Represents shares held of record by a trust for the benefit of certain of Mr. Anderson's immediate family members which were received in connection with the pro rata distribution from North Bridge Growth Equity I, L.P. referenced in footnote 1 above. Mr. Anderson's immediate family member is the trustee of the trust. Mr. Anderson disclaims beneficial ownership of these shares, and the filing of this report is not an admission that Mr. Anderson is the beneficial owner of these securities for purposes of Section 16 or any other purpose.

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