Filing Details

1	NAMES OF REPORTING PERSONS
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
	Thomas H. Lee Advisors, LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☐
				(b)	☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	OO
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			0
		8	SHARED VOTING POWER
			19,244,020(1)
		9	SOLE DISPOSITIVE POWER
			0
		10	SHARED DISPOSITIVE POWER
			19,244,020(1)
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	19,244,020(1)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	18.55% (2)
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	OO

1	NAMES OF REPORTING PERSONS
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY)
	THL Fund VII Coinvestment Partners, L.P.
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP			(a)	☐
				(b)	☒
3	SEC USE ONLY
4	SOURCE OF FUNDS (SEE INSTRUCTIONS)
	OO
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(D) OR 2(E)				☐
6	CITIZENSHIP OR PLACE OF ORGANIZATION
	DELAWARE
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER
			0
		8	SHARED VOTING POWER
			217,962(1)
		9	SOLE DISPOSITIVE POWER
			0
		10	SHARED DISPOSITIVE POWER
			217,962(1)
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
	217,962(1)
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS)				☐
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)
	0.21%(2)
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS)
	PN

This Amendment No. 2 (“Amendment No. 2”) amends and supplements the statement on Schedule 13D originally filed by the Reporting Persons on August 10, 2017 (as amended from time to time, the “Schedule 13D”).  Unless otherwise indicated, each capitalized term used but not defined in this Amendment No. 2 shall have the meaning assigned to such term in the Schedule 13D.

This Schedule 13D relates to the Reporting Persons’ (as defined in Item 2) beneficial ownership interest in the Class A common stock, par value $0.01 per share (the “Common Stock”), of Syneos Health, Inc. (the “Issuer”). The address of the principal executive office of the Issuer is 3201 Beechleaf Court, Suite 600, Raleigh, North Carolina 27604.

(a) This statement is being filed by the following entities:

The entities listed in subparagraphs (1) through (15) above are collectively referred to as the “Reporting Persons” or the “THL Funds”) and each individually as a “Reporting Person” or a “THL Fund.”

THL Holdco, LLC, a Delaware limited liability company (“THL Holdco”) is the Managing Member of THL Advisors, which in turn is the General Partner of Thomas H. Lee Partners, L.P., a Delaware limited partnership (“THL”), which in turn is the Sole Member of Fund VII GP, the Managing Member of Managers VI and Managers VII, and the General Partner of Fund VII Coinvest. Fund VI 2019 GP is the General Partner of Fund VI 2019.  Fund VII GP is the General Partner of Equity Fund VII inVentiv, Equity Fund VII, Parallel Fund VII, Parallel Cayman Fund VII and Executive Fund VII.

(b) The principal office address of each THL Fund is c/o Thomas H. Lee Partners, L.P., 100 Federal St., 35th Floor, Boston, MA 02110.

(c) The principal business of THL is to operate as an investment advisory firm and to make private equity investments. Each of the THL Funds, other than Fund VI 2019 GP and Fund VII GP, is principally engaged in the investment of securities.  Fund VI 2019 GP is principally engaged in the business of serving as the General Partner of Fund VI 2019.  Fund VII GP is principally engaged in the business of serving as a General Partner to Equity Fund VII, among other limited partnerships.

(d)(e) During the last five years, none of the THL Funds has been convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors). During the last five years, none of the THL Funds has been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of which any such person was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to Federal or State securities laws or finding any violations with respect to such laws.

(f)  See Item 2(a) of this Amendment No. 2.

Item 3 is amended and supplemented as follows:

The information set forth under Items 4 and 6 of this Amendment No. 2 is incorporated herein by reference.

Item 4 is supplemented as follows:

The information set forth under Item 6 of this Amendment No. 2 is incorporated herein by reference.

Pursuant to the Purchase Agreement, dated as of April 30, 2019, among Thomas H. Lee Equity Fund VI, L.P. (“Equity Fund VI”), Thomas H. Lee Parallel Fund VI, L.P. (“Parallel Fund VI”), Thomas H. Lee Parallel Fund (DT) VI, L.P. (“Parallel Fund DT VI”), THL Coinvestment Partners, L.P. (“THL Coinvest”), THL Operating Partners, L.P. (“THL Operating”), Putnam Investments Employees’ Securities Company III, LLC (“Putnam III”), Great-West Investors, L.P. (“Great-West”) (collectively, the “Fund VI Entities”) and Fund VI 2019, the Fund VI entities sold an aggregate of 5,504,340 shares of Common Stock to Fund VI 2019 and Fund VI 2019 Coinvest for $238,413,162 or approximately $43.31 per share (the “2019 Fund Transfer”), which funds were obtained from capital contributions made by equity partners of Fund VI 2019 and Fund VI 2019 Coinvest.  Accordingly, upon the completion of the 2019 Fund Transfer on June 24, 2019: Equity Fund VI transferred 3,029,630 shares of Common Stock for $131,224,393; Parallel Fund VI transferred 2,051,504 shares of Common Stock for $88,858,165; Parallel Fund DT VI transferred 358,357 shares of Common Stock for $15,521,756; THL Coinvest transferred 28,433 shares of Common Stock for $1,231,538, THL Operating transferred 5,399 shares of Common Stock for $233,850, Putnam III transferred 15,502 shares of Common Stock for $671,448; and Great-West transferred 15,515 shares of Common Stock for $672,012.  Upon the completion of the 2019 Fund Transfer, Fund VI 2019 directly owned 5,352,591 shares of Common Stock and Fund VI 2019 Coinvest directly owned 151,749 shares of Common Stock.

(a)(b) The responses of the Reporting Persons to Rows (7) through (13) of the cover pages of this Amendment No. 2 as of the date hereof, are incorporated herein by reference.  As of the date hereof, after giving effect to the 2019 Fund Transfer, the Reporting Persons beneficially own, in the aggregate, 19,244,020 shares of Common Stock, which represents 18.55% of the Common Stock issued and outstanding.  The following table sets forth the number of shares and percentage of Common Stock owned by each Reporting Persons named in Item 2 of this Amendment No. 2.  The percentage of Common Stock owned was calculated based upon 103,755,391 shares of Common Stock outstanding as of April 30, 2019 as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the SEC on May 9, 2019.

On account of the THL Stockholders’ Agreement (as defined and more fully described in Item 6 of the Schedule 13D), the Reporting Persons may be deemed to constitute a “group” (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”).

(c) Other than as reported in this Amendment No. 2, no Reporting Person has entered into any transactions in the securities of the Issuer within the last 60 days.

(d) Under certain circumstances, partners or members of a Reporting Person, as the case may be, could have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, shares of Common Stock owned by such Reporting Person.

(e) Not applicable.

On June 24, 2019, in connection with the 2019 Fund Transfer, each of Fund VI 2019 and Fund VI 2019 Coinvest executed a joinder agreement, dated as of June 24, 2019, pursuant to which each of Fund VI 2019 and Fund VI 2019 Coinvest will be deemed to be a party to the THL Stockholders’ Agreement with the same respective rights and obligations as the other THL Funds that are parties thereto as of such date.

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Signature

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

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