Trinseo PLC — Director's Dealing 2015

Jun 29, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Trinseo S.A. (TSE)
CIK: 0001519061
Period of Report: 2015-06-25

Reporting Person: Meisel Seth (Director, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-06-25	Ordinary Shares	A	3236	$0.00	Acquired	3236	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Ordinary Shares	37269567	Indirect

Footnotes

F1: Represents shares subject to restricted stock unit award that will vest in full on the earlier of (a) the first anniversary of the grant date, subject to the grantee's continued service as a member of the Board through such date, or (b) the termination of the grantee's service as a member of the Board as a result of his or her death. If the grantee's service as a member of the Board ceases for any reason other than death, the award, to the extent not already vested, will be automatically and immediately forfeited.

F2: Represents ordinary shares of Trinseo S.A. held by Bain Capital Everest Manager Holding SCA ("BCEM Holding") whose general partner is Bain Capital Everest Manager S.a r.l. ("BCEM"). All of the outstanding share capital of BCEM is held by Bain Capital Europe Fund III, L.P. ("Europe Fund III") and, in that capacity, Europe Fund III has the power to appoint the managers of BCEM. Bain Capital Investors, LLC ("BCI") is the general partner of Bain Capital Partners Europe III, L.P., which is the general partner of Europe Fund III. By virtue of these relationships, BCI may be deemed to share voting and dispositive power with respect to the shares held by BCEM Holding.

F3: In addition to being the general partner of Bain Capital Partners Europe III, L.P., which is the general partner of Europe Fund III, BCI is the general partner of Bain Capital Partners X, L.P., which is the general parter of Bain Capital Fund X, L.P. BCI is also the managing general partner of BCIP Associates IV, L.P., BCIP Associates IV-B, L.P., BCIP Trust Associates IV, L.P. and BCIP Trust Associates IV-B, L.P.

F4: Mr. Meisel is a Managing Director of BCI. By virtue of the relationships described in these footnotes, Mr. Meisel may be deemed to share voting and dispositive power with respect to the shares of Trinseo S.A. held by BCEM Holding. Mr. Meisel disclaims beneficial ownership of such securities except to the extent of his pecuniary interest therein.