Bain Capital Investors Form 4 Change in insider ownership

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

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Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

BAIN CAPITAL INVESTORS LLC

(Last) (First) (Middle)

200 CLARENDON STREET

(Street)

BOSTON MA 02116

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Trinseo S.A. [ TSE ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

Director	X	10% Owner
Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
03/24/2016

4. If Amendment, Date of 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

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
ORDINARY SHARES	03/24/2016		S		10,600,000	D	$35.63	26,669,567	I	See Footnotes(1)(2)(3)

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 Securities Underlying Derivative Security (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: 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

1. Name and Address of Reporting Person^*

BAIN CAPITAL INVESTORS LLC

(Last) (First) (Middle)

200 CLARENDON STREET

(Street)

BOSTON MA 02116

(City) (State) (Zip)

1. Name and Address of Reporting Person^*

BCIP Trust Associates IV-B, L.P.

(Last) (First) (Middle)

JOHN HANCOCK TOWER

200 CLARENDON STREET

(Street)

BOSTON MA 02116

(City) (State) (Zip)

Explanation of Responses:

1. Represents ordinary shares of Trinseo S.A. held by Bain Capital Everest Manager Holding SCA ("BCEM Holding") whose general partner is Bain Capital Everest Manager S.a r.l. ("BCEM"). On March 24, 2016, BCEM Holding sold 10,600,000 Ordinary Shares. Following such sale, BCEM Holding held 26,669,567 Ordinary Shares.

2. All of the outstanding share capital of BCEM is held by Bain Capital Europe Fund III, L.P. ("Europe Fund III") and, in that capacity, Europe Fund III has the power to appoint the managers of BCEM. Bain Capital Investors, LLC ("BCI") is the general partner of Bain Capital Partners Europe III, L.P., which is the general partner of Europe Fund III. In addition to being the general partner of Bain Capital Partners Europe III, L.P., which is the general partner of Europe Fund III, BCI is the general partner of Bain Capital Partners X, L.P., which is the general partner of Bain Capital Fund X, L.P. Boylston Coinvestors, LLC is the general partner of BCIP Associates IV, L.P., BCIP Associates IV-B, L.P., BCIP Trust Associates IV, L.P. and BCIP Trust Associates IV-B, L.P.

3. The governance, investment strategy and decision-making process with respect to the investments held by all of the Bain Capital funds is directed by BCI's Global Private Equity Board. As a result, BCI may be deemed to share voting and dispositive power with respect to the shares of Trinseo S.A. held by BCEM Holding, BCI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.

Remarks:

2 of 2

	BCIP TRUST ASSOCIATES IV-B,L.P. By: Boylston Coinvestors, LLC, its general partner By: /s/ Stephen Thomas, Name: Stephen Thomas, Title: Authorized Signatory	03/28/2016
	** Signature of Reporting Person	Date
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