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 *
THOMAS H. LEE ADVISORS, LLC
  2. Issuer Name and Ticker or Trading Symbol
INC Research Holdings, Inc. [INCR]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
C/O THOMAS H. LEE PARTNERS, L.P., 100 FEDERAL STREET, 35TH FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
08/01/2017
(Street)

BOSTON, MA 02110
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
Class A Common Stock               25,239,664 I See Footnoes (1) (2) (3)
Class A Common Stock 08/01/2017   A   2,178 (4) A (4) (5) 2,178 D  
Class A Common Stock 08/01/2017   A   2,178 (4) A (4) (6) 2,178 D  

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
THOMAS H. LEE ADVISORS, LLC
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
Thomas H. Lee Equity Fund VI, L.P.
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
Thomas H. Lee Parallel (DT) Fund VI, L.P.
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
Thomas H. Lee Parallel Fund VI, L.P.
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
Thomas H. Lee Equity Fund VII, L.P.
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
Thomas H. Lee Parallel Fund VII, L.P.
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
Thomas H. Lee Parallel (Cayman) Fund VII, L.P.
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
ABBRECHT TODD M
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       
Nelson Joshua M
C/O THOMAS H. LEE PARTNERS, L.P.
100 FEDERAL STREET, 35TH FLOOR
BOSTON, MA 02110
       

Signatures

 Thomas H. Lee Advisors, LLC By: THL Holdco, LLC, its Managing Member By: /s/ Charles P. Holden Title: Managing Director   08/03/2017
**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) See Exhibit 99.1 for text of footnote (1).
(2) See Exhibit 99.1 for text of footnote (2).
(3) See Exhibit 99.1 for text of footnote (3).
(4) See Exhibit 99.1 for text of footnote (4).
(5) See Exhibit 99.1 for text of footnote (5).
(6) See Exhibit 99.1 for text of footnote (6).
 
Remarks:
Exhibit 99.1 and Exhibit 99.2 (Joint Filer Information) are incorporated herein by reference. This Form 4 is the first of two Forms 4 being filed relating to the same event. The Form 4 has been split into two filings because there are more than 10 Reporting Persons in total, and the SEC's EDGAR filing system limits a single Form 4 to a maximum of 10 Reporting Persons. Each Form 4 will be filed by Designated Filer Thomas H. Lee Advisors, LLC.

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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