UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K/A

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported): January 12, 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))

ITEM 7.01                                    Regulation FD

On January 19, 2017 a Current Report on Form 8-K, dated January 12, 2017 (File No. 001-36473) was filed erroneously on behalf of Trinseo S.A. (the “Company”) by its service provider without the Company’s authorization.  Investors are advised to disregard this filing as it contains erroneous information, including indicating that certain information and data is published on our website which is currently unavailable.  The Company does plan to publish certain data on historical styrene monomer margin over raw materials along with historical prices of styrene and key raw material inputs of styrene, including providing the current month’s European styrene monomer price, beginning in March 2017.

Note on Forward-Looking Statements

This Current Report and items referenced herein contain “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995. Words such as “expect,” “estimate,” “project,” “assume,” “forecast,” “anticipate,” “intend,” “plan,” “may,” “will,” “could,” “should,” “believes,” “predicts,” “potential,” “would,” and similar expressions are intended to identify such forward-looking statements. Forward-looking statements in this Current Report or referenced herein may include, without limitation, assumptions about market conditions and raw material spot and contract prices, that involve known and unknown risks, uncertainties and other factors that may cause results, levels of activity, performance or achievements to differ materially from results expressed or implied by this Current Report or by materials referenced herein.. Such risk factors include, among others: conditions in the global economy and capital markets, volatility in costs or disruption in the supply of the raw materials utilized for our products; loss of market share to other producers of styrene-based chemical products; compliance with environmental, health and safety laws; changes in laws and regulations applicable to our business; our inability to continue technological innovation and successful introduction of new products; liabilities or lawsuits related to contamination or the release of chemicals; and the loss of customers. Additional risks and uncertainties are set forth in the Company’s reports filed with the United States Securities and Exchange Commission, which are available at http://www.sec.gov/ as well as the Company’s website at http://www.trinseo.com. As a result of the foregoing considerations, you are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date of this Current Report. All forward-looking statements are qualified in their entirety by this cautionary statement. The Company undertakes no obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.

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SIGNATURES

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

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