Trinseo PLC — Regulatory Filings 2025

Aug 7, 2025

S-8 1 tse-20250807xs8.htm S-8 Enhanced HTML document created with Toppan Merrill Bridge 11.0.0.141 Created on: 8/7/2025 03:44:27 PM (UTC)

REGISTRATION NO. 333 –

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM S-8

REGISTRATION STATEMENT

under

the SECURITIES ACT OF 1933

Trinseo PLC

(Exact Name of Registrant as Specified in Its Charter)

Ireland	N/A
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification No.)

440 East Swedesford Road

Suite 301

Wayne, PA 19087

(Address, Including Zip Code, of Principal Executive Offices)

Trinseo PLC Amended and Restated 2014 Omnibus Incentive Plan

(Full Title of the Plan)

Angelo Chaclas

Senior Vice President, Chief Legal Officer and Corporate Secretary

440 East Swedesford Road

Suite 301

Wayne, PA 19087

(610) 240-3200

(Name, Address and Telephone Number, Including Area Code, of Agent For Service)

with copies to:

Craig Marcus

Ropes & Gray LLP

1211 Avenue of the Americas

New York, NY 10036-8704

212 596 9000

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act. (Check one):

​	​	​	​
Large accelerated filer	◻	Accelerated filer	⌧
​	​	Smaller reporting company	◻
Non-accelerated filer	◻	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 7(a)(2)(B) of the Securities Act. ☐

EXPLANATORY NOTE

This Registration Statement on Form S-8 is being filed by the registrant, Trinseo PLC (the “Company”), for the purpose of increasing the number of shares of common stock to be issued under the Trinseo PLC Amended & Restated 2014 Omnibus Incentive Plan (the “Plan”) by 2,425,000 shares, from 7,575,000 shares to 10,000,000 shares. In accordance with General Instruction E to Form S-8, the Company incorporates by reference the contents of the Registration Statement on Form S-8 (Registration No. 333- 273699) filed on August 4, 2023 , Registration Statement on Form S-8 (Registration No. 333- 266696) filed on August 9, 2022 , Registration Statement on Form S-8 (Registration No. 333-240195) filed on July 30, 2020 and Post-Effective Amendment No. 1 to such Registration Statement filed on October 8, 2021 , the Registration Statement on Form S-8 (Registration No. 333-232925) filed on July 31, 2019 and Post-Effective Amendment No. 1 to such Registration Statement filed on October 8, 2021 , and the Registration Statement on Form S-8 (Registration No. 333-196973) filed on June 23, 2014 and Post-Effective Amendment No. 1 to such Registration Statement filed on October 8, 2021 . The shareholders of the Company approved a proposal to amend the Plan for this purpose at the annual general meeting of shareholders on June 25, 2025.

Item 8. Exhibits.

​	​	​
Exhibit Number		Description
​	​	​
4.1	​	Memorandum and Articles of Association of Trinseo PLC (previously filed as Exhibit 3.1 to the Current Report on Form 8-K filed with the SEC on June 17, 2022 and incorporated herein by reference).
​	​	​
4.2	​	Trinseo PLC Amended and Restated 2014 Omnibus Incentive Plan (previously filed as Exhibit 10.1 to the Current Report on Form 8-K filed with the SEC on June 26, 2025 and incorporated herein by reference).
​	​	​
5.1	​	Opinion of McCann Fitzgerald.
​	​	​
23.1	​	Consent of PricewaterhouseCoopers LLP.
​	​	​
23.2	​	Consent of Deloitte & Touche LLP.
​	​	​
23.3	​	Consent of McCann Fitzgerald (included in Exhibit 5.1).
​	​	​
24.1	​	Powers of Attorney (included on the signature page of this Registration Statement).
​	​	​
107	​	Calculation of Filing Fee Table

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SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Wayne, Commonwealth of Pennsylvania on the 7th day of August, 2025.

​	​	​
​	TRINSEO PLC
​	​
​	By:	/s/ Frank A. Bozich
​	Name:	Frank A. Bozich
​	Title:	President and Chief Executive Officer

POWER OF ATTORNEY

Each officer and director of Trinseo PLC whose signature appears below constitutes and appoints Frank A. Bozich and David Stasse, and each of them singly, his true and lawful attorneys-in-fact and agents, with full power of substitution and resubstitution in each of them singly, for him and in his name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement on Form S-8 of Trinseo PLC, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting to the attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing requisite or necessary to be done in or about the premises, as full to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that the attorneys-in-fact and agents or any of each of them or their substitutes may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act of 1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.

​	​	​	​	​
Signature		Title		Date
​	​	​	​	​
/s/ Frank A. Bozich	​	Director, President and Chief Executive Officer (Principal Executive Officer)	​	August 7, 2025
Frank A. Bozich	​	​	​	​
​	​	​	​	​
/s/ David Stasse	​	Executive Vice President and Chief Financial Officer (Principal Financial Officer)	​	August 7, 2025
David Stasse	​	​	​	​
​	​	​	​	​
/s/ Roger Greene	​	Vice President, Global Controller & PAO (Principal Accounting Officer)	​	August 7, 2025
Roger Greene	​	​	​	​
​	​	​	​	​
/s/ K’Lynne Johnson	​	Director	​	August 7, 2025
K’Lynne Johnson	​	​	​	​
​	​	​	​	​
/s/ Joseph Alvarado	​	Director	​	August 7, 2025
Joseph Alvarado	​	​	​	​
​	​	​	​	​
/s/ Victoria Brifo	​	Director	​	August 7, 2025
Victoria Brifo	​	​	​	​
​	​	​	​	​
/s/ Jeffrey J. Cote	​	Director	​	August 7, 2025

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Jeffrey J. Cote	​	​	​	​
​	​	​	​	​
/s/ Jeanmarie Desmond	​	Director	​	August 7, 2025
Jeanmarie Desmond	​	​	​	​
​	​	​	​	​
/s/ Matthew Farrell	​	Director	​	August 7, 2025
Matthew Farrell	​	​	​	​
​	​	​	​	​
/s/ Sandra Beach Lin	​	Director	​	August 7, 2025
Sandra Beach Lin	​	​	​	​
​	​	​	​	​
/s/ Henri Steinmetz	​	Director	​	August 7, 2025
Henri Steinmetz	​	​	​	​
​	​	​	​	​

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