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): June 21, 2016

Trinseo S.A.

(Exact name of registrant as specified in its charter)

001-36473

(Commission File Number)

(610) 240-3200

(Registrant’s telephone number, including area code)

Not Applicable

(Former name or former address, if changed since last report)

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:

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 5.07                                           Submission of Matters to a Vote of Security Holders.

On June 21, 2016, Trinseo S.A. (the “Company”) held its Annual General Meeting of Shareholders (the “General Meeting”) pursuant to notice duly given. A total of 44,120,509 ordinary shares were present or represented by proxy, which accounted for approximately 93.51% of the shares entitled to vote at the General Meeting. The Company’s shareholders voted on the following eleven proposals and cast their votes as set forth below.

Proposal One: The Election of Three Class II Directors

The Company’s shareholders approved the election of the Company’s Class II Director nominees by the votes set forth in the table below:

Proposal Two:  Ratification of the Appointment of Stephen F. Thomas as a Class III Director

The Company’s shareholders ratified the appointment of Mr. Thomas as a Class III Director by the votes set forth in the table below:

Proposal Three:  Ratification of the Company’s Directors’ Compensation Program

The Company’s shareholders ratified the appointment of the Company’s directors’ compensation program by the votes set forth in the table below:

Proposal Four:  Approval, on an Advisory Basis, of the Company’s Named Executive Officer Compensation

The Company’s shareholders approved on an advisory basis the compensation paid to the Company’s named executive officers in 2015 and described in its proxy statement by the votes set forth in the table below:

Proposal Five:  Approval of the Company’s Luxembourg Statutory Accounts

The Company’s shareholders approved the Luxembourg Statutory Accounts as of and for the year ended December 31, 2015, showing total assets of $482.8 million and a loss for the year then ended of $15.9 million by the votes set forth in the table below:

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Proposal Six: Approval of the Allocation of the Results of the Financial Year Ended December 31, 2015

The Company’s shareholders approved that the $15.9 million loss for the year ended December 31, 2015 carry forward to the following year by the votes set forth in the table below:

Proposal Seven: Approval of the Granting of Discharge to the Directors and Independent Auditor for the Performance of their Respective Duties During the Year Ended December 31, 2015

The Company’s shareholders approved the granting of discharge to the directors and independent auditor for the performance of their duties during the year ended December 31, 2015 by the votes set forth in the table below:

Proposal Eight: Ratification of the Appointment of the Company’s Independent Auditor for All Statutory Accounts

The Company’s shareholders ratified the appointment of PricewaterhouseCoopers Société coopérative to be the Company’s independent auditor for all statutory accounts required under Luxembourg law for the year ended December 31, 2016 by the votes set forth in the table below:

Proposal Nine: Ratification of the Appointment of the Company’s Independent Registered Account Firm

The Company’s shareholders ratified the appointment of PricewaterhouseCoopers LLP to be the Company’s independent registered accounting firm for the year ended December 31, 2016 by the votes set forth in the table below:

Proposal Ten: Authorize the Board to Make Repayments of Equity

The Company’s shareholders authorized the Board to approve repayments of equity in amounts and at intervals determined in their discretion and within limits of Luxembourg law by the votes set forth in the table below:

Proposal Eleven: Authorize the Board to Repurchase Up To 4.5 Million Ordinary Shares

The Company’s shareholders authorized the Board to repurchase up to 4.5 million of its outstanding ordinary shares over the next two years by the votes set forth in the table below:

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Item 8.01            Other Events

Repayment of Equity

On June 22, 2016, the Company’s Board of Directors declared a repayment of equity of $0.30 per ordinary share payable on July 20, 2016 to owners of record as of close of business on July 6, 2016.  A copy of the Company’s press release announcing this cash distribution to shareholders is attached as Exhibit 99.1 hereto and incorporated herein by reference.

Share Repurchase Program

On June 22, 2016, the Company’s Board of Directors authorized a share repurchase program (the “Share Repurchase Program”), pursuant to which the Company may, from time to time, purchase its ordinary shares for an aggregate repurchase price not to exceed $100 million. Share repurchases may be executed open market transactions or other means. The Share Repurchase Program does not have an expiration date and does not obligate the Company to purchase any shares. The authorization for the Share Repurchase Program may be terminated, increased or decreased by the Company’s Board of Directors at any time.  A copy of the Company’s press release announcing the Share Repurchase Program is attached as Exhibit 99.2

Item 9.01            Financial Statements Exhibits

(d) Exhibits

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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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