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): November 28, 2017

Trinseo S.A.

(Exact name of registrant as specified in its charter)

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):

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

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

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

o          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 o

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. o

Item 5.07                                                                             Submission of Matters to a Vote of Security Holders.

On November 28, 2017, Trinseo S.A. (the “Company”) held an Extraordinary General Meeting of Shareholders (the “General Meeting”) pursuant to notice duly given. A total of 36,694,349 ordinary shares were present or represented by proxy, which accounted for approximately 83.96% of the shares entitled to vote at the General Meeting. The Company’s shareholders voted on the following proposal and cast their votes as set forth below.

Proposal One: Election of Class III Director

The Company’s shareholders approved the election of the Company’s Class III Director nominee, Mr. Henri Steinmetz, by the votes set forth in the table below:

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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.

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