UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): February 24, 2019

Trinseo S.A.

(Exact name of registrant as specified in its charter)

Luxembourg	001-36473	N/A
(State or other jurisdiction of incorporation or organization)	(Commission File Number)	(I.R.S. Employer Identification Number)

1000 Chesterbrook Boulevard, Suite 300,

Berwyn, Pennsylvania 19312

(Address of principal executive offices, including zip code)

(610) 240-3200

(Telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

☐      Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

☐      Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

☐      Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

☐      Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

ITEM 5.02Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.

(b)  Departure of Directors or Certain Officers

On February 24, 2019, Barry J. Niziolek, Executive Vice President and Chief Financial Officer of Trinseo. S.A. (the “Company”) notified the Company of his intention to retire mid-year 2019.

ITEM 7.01 Regulation FD Disclosure.

On February 27, 2019, the Company issued a press release announcing Mr. Niziolek’s retirement. A copy of the press release is furnished as Exhibit 99.1 hereto.

The information contained in this Item 7.01 and in Exhibit 99.1 shall not be deemed filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or otherwise subject to liability of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, except as shall be expressly set forth by specific reference in such filing.

ITEM 9.01.Financial Statements and Exhibits

(d) Exhibits

Exhibit Number	Description
99.1	Press Release, dated February 27, 2019

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EXHIBIT INDEX

Exhibit Number	Description
99.1	Press Release, dated February 27, 2019

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	TRINSEO S.A.
	By:	/s/ Angelo N. Chaclas
	Name:	Angelo N. Chaclas
	Title:	Senior Vice President, Chief Legal Officer, Chief Compliance Officer & Corporate Secretary
Date: February 27, 2019

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