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 *
TA ASSOCIATES INC
  2. Issuer Name and Ticker or Trading Symbol
PROS Holdings, Inc. [PRO]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
_____ Officer (give title below) __X__ Other (specify below)
See General Remarks
(Last)
(First)
(Middle)
JOHN HANCOCK TOWER, 200 CLARENDON ST, 56TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
09/15/2008
(Street)

BOSTON, MA 02116
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 09/15/2008   J(1)   1,636,424 D (11) 0 I See Footnote 2 (2)
Common Stock 09/15/2008   J(3)   353,468 A (11) 353,468 I See Footnote 4 (4)
Common Stock 09/15/2008   J(5)   353,468 D (11) 0 I See Footnote 6 (6)
Common Stock 09/15/2008   J(7)   3,273 A (11) 6,473 D  
Common Stock 09/15/2008   J(8)   32,727 D (11) 0 I See Footnote 9 (9)
Common Stock               30,095 I See Footnote 10 (10)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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
TA ASSOCIATES INC
JOHN HANCOCK TOWER
200 CLARENDON ST, 56TH FLOOR
BOSTON, MA 02116
      See General Remarks
TA ADVENT VIII LP
JOHN HANCOCK TOWER
200 CLARENDON ST, 56TH FLOOR
BOSTON, MA 02116
      See General Remarks
TA ASSOCIATES VIII LLC
JOHN HANCOCK TOWER
200 CLARENDON ST, 56TH FLOOR
BOSTON, MA 02116
      See General Remarks
TA EXECUTIVES FUND LLC
JOHN HANCOCK TOWER
200 CLARENDON ST, 56TH FLOOR
BOSTON, MA 02116
      See General Remarks
TA INVESTORS LLC
JOHN HANCOCK TOWER
200 CLARENDON ST, 56TH FLOOR
BOSTON, MA 02116
      See General Remarks

Signatures

 TA Associates, Inc., By Thomas P. Alber, Chief Financial Officer   09/16/2008
**Signature of Reporting Person Date

 TA/Advent VIII L.P., By TA Associates VIII LLC, Its General Partner, By TA Associates, Inc., Its Manager, By Thomas P. Alber, Chief Financial Officer   09/16/2008
**Signature of Reporting Person Date

 TA Associates VIII LLC, By TA Associates, Inc., Its Manager, By Thomas P. Alber, Chief Financial Officer   09/16/2008
**Signature of Reporting Person Date

 TA Investors LLC, By TA Associates, Inc., Its Manager, By Thomas P. Alber, Chief Financial Officer   09/16/2008
**Signature of Reporting Person Date

 TA Executives Fund LLC, By TA Associates, Inc., Its Manager, By Thomas P. Alber, Chief Financial Officer   09/16/2008
**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) TA/Advent VIII L.P. distributed 1,636,424 shares pro rata for no consideration to the partners of TA/Advent VIII L.P. in a transaction exempt under Rule 16a-9(a).
(2) These securities are owned solely by TA/Advent VIII L.P. TA Associates, Inc. is the Manager of TA Associates VIII LLC, which is the General Partner of TA/Advent VIII L.P. Each of TA Associates, Inc. and TA Associates VIII LLC may be deemed to have a beneficial interest in shares held by TA/Advent VIII L.P. and each disclaims beneficial ownership of such shares, except to the extent of its pecuniary interest in such shares which is subject to indeterminable future events.
(3) TA Associates VIII LLC is the General Partner and a Limited Partner of TA/Advent VIII L.P. and received 353,468 shares from TA/Advent VIII L.P. in a pro rata distribution for no consideration in a transaction exempt under Rule 16a-9(a).
(4) These securities are owned solely by TA Associates VIII LLC. TA Associates, Inc. is the Manager of TA Associates VIII LLC, which is the General Partner of TA/Advent VIII L.P. TA Associates, Inc. may be deemed to have a beneficial interest in shares held by TA Associates VIII LLC and disclaims beneficial interest of such shares, except to the extent of its pecuniary interest in 3,273 shares.
(5) TA Associates VIII LLC distributed 353,468 shares pro rata for no consideration to the partners of TA Associates VIII LLC in a transaction exempt under Rule 16a-9(a).
(6) These securities are owned solely by TA Associates VIII LLC. TA Associates, Inc. is the Manager of TA Associates VIII LLC, which is the General Partner of TA/Advent VIII L.P. TA Associates, Inc. may be deemed to have a beneficial interest in shares held by TA Associates VIII LLC and disclaims beneficial interest of such shares, except to the extent of its pecuniary interest in such shares which is subject to indeterminable future events.
(7) TA Associates, Inc. is the General Partner of TA Associates VIII LLC and received 3,273 shares from TA Associates VIII LLC in a pro rata distribution for no consideration in a transaction exempt under Rule 16a-9(a).
(8) TA Investors LLC distributed 32,727 shares pro rata for no consideration to the partners of TA Investors LLC in a transaction exempt under Rule 16a-9(a).
(9) These securities are owned solely by TA Investors LLC. TA Associates, Inc. is the Manager of TA Investors LLC. TA Associates, Inc. may be deemed to have a beneficial interest in shares held by TA Investors LLC and disclaims beneficial ownership of such shares.
(10) These securities are owned solely by TA Executives Fund LLC. TA Associates, Inc. is the Manager of TA Executives Fund LLC. TA Associates, Inc. may be deemed to have a beneficial interest in shares held by TA Executives Fund LLC and disclaims beneficial ownership of such shares.
(11) Not Applicable
 
Remarks:
The Reporting Persons are members of a 13(d) group.  The Reporting Persons have a representative on the Issuer's board of directors.  Kurt R. Jaggers currently serves as the Reporting Persons' representative on the board of directors and, as such, the Reporting Persons are deemed directors of the Issuer.

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