REGISTRATION RIGHTS AGREEMENT by and among TRINSEO MATERIALS OPERATING S.C.A., TRINSEO MATERIALS FINANCE, INC. and the Guarantors party hereto and DEUTSCHE BANK SECURITIES INC. Dated as of January 29, 2013

Exhibit 4.6

REGISTRATION RIGHTS AGREEMENT

by and among

TRINSEO MATERIALS OPERATING S.C.A.,

TRINSEO MATERIALS FINANCE, INC.

and the Guarantors party hereto

and

DEUTSCHE BANK SECURITIES INC.

Dated as of January 29, 2013

REGISTRATION RIGHTS AGREEMENT

This Registration Rights Agreement (this “Agreement”) is made and entered into as of January 29, 2013, by and among Trinseo Materials Operating S.C.A., a partnership limited by shares (société en commandite par actions) organized and existing under the laws of the Grand Duchy of Luxembourg, having its registered office at 0X, xxx Xxxxxxx Xxxxxxxx X-0000 Xxxxxxxx Grand-Duché de Luxembourg, and registered with the Luxembourg Trade and Companies Register under number B 153586 (the “Company”), Trinseo Materials Finance, Inc., a Delaware Corporation (“Trinseo Finance,” and together with the Company, the “Issuers”), the guarantors party hereto (collectively, the “Guarantors”) and Deutsche Bank Securities Inc., as representative for the several Initial Purchasers listed on Schedule I to the Purchase Agreement (as defined below) (collectively, the “Initial Purchasers”), all of whom have agreed to purchase the Issuers’ 8.75% Senior Secured Notes due 2019 (the “Initial Notes”), guaranteed by the Guarantors (the “Guarantees”) pursuant to the Purchase Agreement (as defined below). The Initial Notes and their respective Guarantees are herein collectively referred to as the “Initial Securities.” Within 90 days after the Closing Date (as defined in the Purchase Agreement), each Guarantor that was originally not a party to the Purchase Agreement will execute a joinder agreement in the form of Exhibit A hereto (the “Joinder Agreement”) pursuant to which such Guarantors will become party to this Agreement.

This Agreement is made pursuant to the Purchase Agreement, dated January 29, 2013 (the “Purchase Agreement”), among the Issuers, the Guarantors and the Initial Purchasers (i) for the benefit of the Initial Purchasers and (ii) for the benefit of the holders from time to time of the Initial Securities, including the Initial Purchasers. In order to induce the Initial Purchasers to purchase the Initial Securities, the Issuers have agreed to provide the registration rights set forth in this Agreement.

The parties hereby agree as follows:

SECTION 1. Definitions. As used in this Agreement, the following capitalized terms shall have the following meanings:

Additional Interest Payment Date: With respect to the Initial Securities, each Interest Payment Date.

Broker-Dealer: Any broker or dealer registered under the Exchange Act.

Business Day: Any day other than a Saturday, Sunday or U.S. federal holiday or a day on which banking institutions or trust companies located in New York, New York are authorized or obligated to be closed.

Closing Date: The date of this Agreement.

Commission: The Securities and Exchange Commission.

Consummate: A registered Exchange Offer shall be deemed “Consummated” for purposes of this Agreement upon the occurrence of (i) the filing and effectiveness under the Securities

Act of the Exchange Offer Registration Statement relating to the Exchange Securities to be issued in the Exchange Offer, (ii) the maintenance of such Registration Statement continuously effective and the keeping of the Exchange Offer open for a period not less than the minimum period required pursuant to Section 3(b) hereof, and (iii) the delivery by the Issuers to the Registrar under the Indenture of Exchange Securities in the same aggregate principal amount as the aggregate principal amount of Initial Securities that were tendered by Holders thereof pursuant to the Exchange Offer.

Effectiveness Target Date: As defined in Section 5 hereof.

Exchange Act: The Securities Exchange Act of 1934, as amended.

Exchange Offer: The registration by the Issuers and the Guarantors under the Securities Act of the Exchange Securities pursuant to a Registration Statement pursuant to which the Issuers and the Guarantors offer the Holders of all outstanding Transfer Restricted Securities the opportunity to exchange all such outstanding Transfer Restricted Securities held by such Holders for Exchange Securities in an aggregate principal amount equal to the aggregate principal amount of the Transfer Restricted Securities tendered in such exchange offer by such Holders.

Exchange Offer Registration Statement: The Registration Statement relating to the Exchange Offer, including the related Prospectus.

Exchange Securities: The 8.75% Senior Secured Notes due 2019 of the same series under the Indenture as the Initial Securities, to be issued to Holders in exchange for Transfer Restricted Securities pursuant to this Agreement.

FINRA: Financial Industry Regulatory Authority.

Holders: As defined in Section 2(b) hereof.

Indemnified Holder: As defined in Section 8(a) hereof.

Indenture: The Indenture, dated as of January 29, 2013, by and between the Issuers, the Guarantors and Wilmington Trust, National Association, as trustee (the “Trustee”), pursuant to which the Securities are to be issued, as such Indenture is amended or supplemented from time to time in accordance with the terms thereof.

Initial Notes: As defined in the preamble hereto.

Initial Placement: The issuance and sale by the Issuers of the Initial Securities to the Initial Purchasers pursuant to the Purchase Agreement.

Initial Purchasers: As defined in the preamble hereto.

Initial Securities: As defined in the preamble hereto.

Interest Payment Date: As defined in the Indenture and the Securities.

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Person: An individual, partnership, corporation, trust or unincorporated organization, or a government or agency or political subdivision thereof.

Prospectus: The prospectus included in a Registration Statement, as amended or supplemented by any prospectus supplement and by all other amendments thereto, including post-effective amendments, and all material incorporated by reference into such Prospectus.

Registration Default: As defined in Section 5 hereof.

Registration Statement: Any registration statement of the Issuers relating to (a) an offering of Exchange Securities pursuant to an Exchange Offer or (b) the registration for resale of Transfer Restricted Securities pursuant to the Shelf Registration Statement, which is filed pursuant to the provisions of this Agreement, in each case, including the Prospectus included therein, all amendments and supplements thereto (including post-effective amendments) and all exhibits and material incorporated by reference therein.

Securities: Collectively, the Initial Securities and the Exchange Securities.

Securities Act: The Securities Act of 1933, as amended.

Shelf Filing Deadline: As defined in Section 4(a) hereof.

Shelf Registration Statement: As defined in Section 4(a) hereof.

Transfer Restricted Securities: Each Initial Security, until the earliest to occur of (a) the date on which such Initial Security is exchanged in the Exchange Offer for an Exchange Security entitled to be resold to the public by the Holder thereof without complying with the prospectus delivery requirements of the Securities Act, (b) the date on which such Initial Security has been effectively registered under the Securities Act and disposed of in accordance with a Shelf Registration Statement and (c) the date on which such Initial Security is distributed to the public by a Broker-Dealer pursuant to the “Plan of Distribution” contemplated by the Exchange Offer Registration Statement (including delivery of the Prospectus contained therein).

Trust Indenture Act: The Trust Indenture Act of 1939, as amended.

SECTION 2. Securities Subject to this Agreement.

(a) Transfer Restricted Securities. The securities entitled to the benefits of this Agreement are the Transfer Restricted Securities.

(b) Holders of Transfer Restricted Securities. A Person is deemed to be a holder of Transfer Restricted Securities (each, a “Holder”) whenever such Person owns Transfer Restricted Securities.

SECTION 3. Registered Exchange Offer.

(a) Unless the Exchange Offer shall not be permissible under applicable law or Commission policy (after the applicable procedures set forth in Section 6(a) hereof have been

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complied with), each of the Issuers and the Guarantors shall (i) cause to be filed with the Commission, a Registration Statement under the Securities Act relating to the Exchange Securities and the Exchange Offer, (ii) use its reasonable best efforts to cause such Registration Statement to become effective, (iii) in connection with the foregoing, (A) file all pre-effective amendments to such Registration Statement as may be necessary in order to cause such Registration Statement to become effective, (B) if applicable, file a post-effective amendment to such Registration Statement pursuant to Rule 430A under the Securities Act and (C) cause all necessary filings in connection with the registration and qualification of the Exchange Securities to be made under the state securities or blue sky laws of such jurisdictions as are necessary to permit Consummation of the Exchange Offer, (iv) upon the effectiveness of such Registration Statement, commence the Exchange Offer and (v) use their reasonable best efforts to complete the Exchange Offer not later than 60 days after such Registration Statement becomes effective. The Exchange Offer shall be on the appropriate form permitting registration of the Exchange Securities to be offered in exchange for the Transfer Restricted Securities and to permit resales of Initial Securities held by Broker-Dealers as contemplated by Section 3(c) hereof.

(b) The Issuers and the Guarantors shall use their reasonable best efforts to cause the Exchange Offer Registration Statement to be effective continuously and shall keep the Exchange Offer open for a period of not less than the minimum period required under applicable federal and state securities laws to Consummate the Exchange Offer; provided, however, that in no event shall such period be less than 30 days after the date notice of the Exchange Offer is mailed to the Holders. The Issuers shall cause the Exchange Offer to comply with all applicable federal and state securities laws. No securities other than the Exchange Securities shall be included in the Exchange Offer Registration Statement. The Issuers shall use their reasonable best efforts to cause the Exchange Offer to be Consummated no later than 365 days after the Closing Date (or if such 365th day is not a Business Day, the next succeeding Business Day).

(c) The Issuers shall indicate in a “Plan of Distribution” section contained in the Prospectus forming a part of the Exchange Offer Registration Statement that any Broker-Dealer who holds Initial Securities that are Transfer Restricted Securities and that were acquired for its own account as a result of market-making activities or other trading activities (other than Transfer Restricted Securities acquired directly from the Issuers), may exchange such Initial Securities pursuant to the Exchange Offer; however, such Broker-Dealer may be deemed to be an “underwriter” within the meaning of the Securities Act and must, therefore, deliver a prospectus meeting the requirements of the Securities Act in connection with any resales of the Exchange Securities received by such Broker-Dealer in the Exchange Offer, which prospectus delivery requirement may be satisfied by the delivery by such Broker-Dealer of the Prospectus contained in the Exchange Offer Registration Statement. Such “Plan of Distribution” section shall also contain all other information with respect to such resales by Broker-Dealers that the Commission may require in order to permit such resales pursuant thereto, but such “Plan of Distribution” shall not name any such Broker-Dealer or disclose the amount of Initial Securities held by any such Broker-Dealer except to the extent required by the Commission as a result of a change in policy after the date of this Agreement.

Each of the Issuers and the Guarantors shall use its reasonable best efforts to keep the Exchange Offer Registration Statement continuously effective, supplemented and amended as required by the provisions of Section 6(c) hereof to the extent necessary to ensure that it is available

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for resales of Initial Securities acquired by Broker-Dealers for their own accounts as a result of market-making activities or other trading activities, and to ensure that it conforms in all material respects with the requirements of this Agreement, the Securities Act and the policies, rules and regulations of the Commission as announced from time to time, for a period ending on the earlier of (i) 180 days from the date on which the Exchange Offer Registration Statement is declared effective and (ii) the date on which a Broker-Dealer is no longer required to deliver a prospectus in connection with market-making or other trading activities.

The Issuers shall provide sufficient copies of the latest version of such Prospectus to Broker-Dealers promptly upon request at any time during such 180-day (or shorter as provided in the foregoing sentence) period in order to facilitate such resales.

SECTION 4. Shelf Registration.

(a) Shelf Registration. If (i) the Issuers determine in good faith that they are not required to file an Exchange Offer Registration Statement or to Consummate the Exchange Offer because the Exchange Offer is not permitted by applicable law or Commission policy (after the applicable procedures set forth in Section 6(a) hereof have been complied with), (ii) for any reason the Exchange Offer is not Consummated within 365 days after the Closing Date (or if such 365th day is not a Business Day, the next succeeding Business Day), or (iii) with respect to any Holder of Transfer Restricted Securities such Holder notifies the Issuers that (A) such Holder is prohibited by applicable law or Commission policy from participating in the Exchange Offer, or (B) such Holder may not resell the Exchange Securities acquired by it in the Exchange Offer to the public without delivering a prospectus and that the Prospectus contained in the Exchange Offer Registration Statement is not appropriate or available for such resales by such Holder, or (C) such Holder is a Broker-Dealer and holds Initial Securities acquired directly from the Issuers or one of their affiliates, then, upon such Holder’s request, the Issuers and the Guarantors shall

(i) cause to be filed a shelf registration statement pursuant to Rule 415 under the Securities Act, which may be an amendment to the Exchange Offer Registration Statement (in either event, the “Shelf Registration Statement”) on or prior to the 45th day after the date such obligation arises but no earlier than the 365th day after the Closing Date (or if such 365th day is not a Business Day, the next succeeding Business Day) (such date being the “Shelf Filing Deadline”), which Shelf Registration Statement shall provide for resales of all Transfer Restricted Securities the Holders of which shall have provided the information required pursuant to Section 4(b) hereof; and

(ii) use their commercially reasonable efforts to cause such Shelf Registration Statement to be declared effective as promptly as practicable, but no later than (A) 90 days after the Shelf Filing Deadline (or if such 90th day is not a Business Day the next succeeding Business Day), or (B) 60 days after the Shelf Filing Deadline if the Shelf Registration Statement is not reviewed by the Commission (or if such 60th day is not a Business Day, the next succeeding Business Day).

Each of the Issuers and the Guarantors shall use its commercially reasonable efforts to keep such Shelf Registration Statement continuously effective, supplemented and amended as required by the provisions of Sections 6(b) and (c) hereof to the extent necessary to ensure that it

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is available for resales of Initial Securities by the Holders of Transfer Restricted Securities entitled to the benefit of this Section 4(a), and to ensure that it conforms with the requirements of this Agreement, the Securities Act and the policies, rules and regulations of the Commission as announced from time to time, from the date on which such Shelf Registration Statement is declared effective by the Commission until the one year anniversary thereof (or shorter period that will terminate when all the Initial Securities covered by such Shelf Registration Statement have been sold pursuant to such Shelf Registration Statement).

(b) Provision by Holders of Certain Information in Connection with the Shelf Registration Statement. No Holder of Transfer Restricted Securities may include any of its Transfer Restricted Securities in any Shelf Registration Statement pursuant to this Agreement unless and until such Holder furnishes to the Issuers in writing, within 20 Business Days after receipt of a request therefor, such information as the Issuers may reasonably request for use in connection with any Shelf Registration Statement or Prospectus or preliminary Prospectus included therein. No Holder of Transfer Restricted Securities shall be entitled to Additional Interest pursuant to a Registration Default with respect to any Shelf Registration Statement as set forth in Section 5 hereof unless and until such Holder shall have provided all such information. Each Holder as to which any Shelf Registration Statement is being effected agrees to furnish promptly to the Issuers all information required to be disclosed in order to make the information previously furnished to the Issuers by such Holder not materially misleading.

(c) Suspension. Notwithstanding anything to the contrary and subject to the limitation set forth in the next succeeding paragraph, at any time after the effectiveness of the Shelf Registration Statement, the Issuers shall be entitled to suspend their obligation to file any amendment to the Shelf Registration Statement, furnish any supplement or amendment to a Prospectus included in the Shelf Registration Statement, make any other filing with the Commission, cause the Shelf Registration Statement or other filing with the Commission to remain effective or take any similar action (collectively, “Registration Actions”) upon (A) the issuance by the Commission of a stop order suspending the effectiveness of the Shelf Registration Statement or the initiation of proceedings with respect to the Shelf Registration Statement under Section 8(d) or 8(e) of the Securities Act, (B) the occurrence of any event or the existence of any fact as a result of which the Shelf Registration Statement would or shall contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading, or the related Prospectus would or shall contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading or (C) the occurrence or existence of any corporate development that, in the good faith determination of the Boards of Directors of the Issuers, makes it appropriate to postpone or suspend the availability of the Shelf Registration Statement and the related Prospectus. Upon the occurrence of any of the conditions described in clause (A), (B) or (C) above, the Issuers shall give prompt notice (a “Suspension Notice”) thereof to the Holders. Upon the termination of such condition, the Issuers shall give prompt notice thereof to the Holders and shall promptly proceed with all Registration Actions that were suspended pursuant to this paragraph.

The Issuers may only suspend Registration Actions pursuant to the preceding paragraph on no more than two occasions for a period (a “Suspension Period”) not to exceed, in the aggregate, (x) forty-five (45) days in any three month period or (y) ninety (90) days in any twelve

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month period. Any Suspension Period will not alter the obligations of the Issuers to pay Additional Interest under the circumstances set forth in Section 5 hereof, if applicable. Each Suspension Period shall be deemed to begin on the date the relevant Suspension Notice is given to the Holders and shall be deemed to end on the earlier to occur of (1) the date on which the Issuers give the Holders a notice that the Suspension Period has terminated and (2) the date on which the number of days during which a Suspension Period has been in effect exceeds, in the aggregate, (x) forty-five (45) days in any three month period or (y) ninety (90) days in any twelve month period; provided that the one year period referred to in the last paragraph of Section 5(a) hereof during which the Shelf Registration Statement is required to be effective and usable shall be extended by the number of days during which such Registration Statement was not effective or usable pursuant to the foregoing provisions (which such extension shall be the Holders’ sole remedy for the exercise by the Issuers and the Guarantors of the Suspension Rights during the time period permitted hereunder, but only to the extent that any suspension period does not violate the 45-day period or 90-day period set forth above).

SECTION 5. Additional Interest.

If (i) any of such Registration Statements has not been declared effective by the Commission on or prior to the date specified for such effectiveness in this Agreement (the “Effectiveness Target Date”), (ii) the Exchange Offer has not been Consummated within 30 Business Days after the Effectiveness Target Date with respect to the Exchange Offer Registration Statement or (iii) any Registration Statement required by this Agreement is filed and declared effective but shall thereafter cease to be effective or fail to be usable for its intended purpose without (in each case other than during a Suspension Period) being succeeded immediately by a post-effective amendment to such Registration Statement that cures such failure and that is itself immediately declared effective (each such event referred to in clauses (i) through (iii), a “Registration Default”), the Issuers hereby agree that the interest rate borne by the Transfer Restricted Securities shall be increased by 0.25% per annum during the 90-day period immediately following the occurrence of any Registration Default and shall increase by 0.25% per annum at the end of each subsequent 90-day period (such increase, “Additional Interest”) until such Registration Default has been cured, but in no event shall such increase exceed 1.00% per annum. Following the cure of all Registration Defaults relating to any particular Transfer Restricted Securities, the interest rate borne by the relevant Transfer Restricted Securities will be reduced to the original interest rate borne by such Transfer Restricted Securities; provided, however, that, if after any such reduction in interest rate, a different Registration Default occurs, the interest rate borne by the relevant Transfer Restricted Securities shall again be increased pursuant to the foregoing provisions; provided further, that the Issuers shall in no event be required to pay Additional Interest for more than one Registration Default at any given time.

All obligations of the Issuers and the Guarantors set forth in the preceding paragraph that are outstanding with respect to any Transfer Restricted Security at the time such security ceases to be a Transfer Restricted Security shall survive until such time as all such obligations with respect to such security shall have been satisfied in full.

Notwithstanding anything to the contrary herein, the increased interest rate described in this Section 5 is the sole and exclusive remedy available to the Holders due to a Registration Default, so long as the Issuers and the Guarantors are acting in good faith hereunder, including, without limitation, with respect to satisfying their obligations under this Agreement.

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SECTION 6. Registration Procedures.

(a) Exchange Offer Registration Statement. In connection with the Exchange Offer, the Issuers and the Guarantors shall comply with all of the provisions of Section 6(c) hereof, shall use their commercially reasonable efforts to effect such exchange to permit the sale of Transfer Restricted Securities being sold in accordance with the intended method or methods of distribution thereof, provided that:

(i) As a condition to its participation in the Exchange Offer pursuant to the terms of this Agreement, each Holder of Transfer Restricted Securities shall furnish, upon the request of the Issuers, prior to the Consummation thereof, a written representation to the Issuers (which may be contained in the letter of transmittal contemplated by the Exchange Offer Registration Statement) to the effect that (A) it is not an affiliate of the Issuers, (B) it is not engaged in, and does not intend to engage in, and has no arrangement or understanding with any Person to participate in, a distribution of the Exchange Securities to be issued in the Exchange Offer and (C) it is acquiring the Exchange Securities in its ordinary course of business. In addition, all such Holders of Transfer Restricted Securities shall otherwise cooperate in the Issuers’ preparations for the Exchange Offer. Each Holder hereby acknowledges and agrees that any Broker-Dealer and any such Holder using the Exchange Offer to participate in a distribution of the securities to be acquired in the Exchange Offer (1) could not under Commission policy as in effect on the date of this Agreement rely on the position of the Commission enunciated in Xxxxxx Xxxxxxx and Co., Inc. (available June 5, 1991) and Exxon Capital Holdings Corporation (available May 13, 1988), as interpreted in the Commission’s letter to Shearman & Sterling dated July 2, 1993, and similar no-action letters (which may include any no-action letter obtained pursuant to clause (i) above), and (2) must comply with the registration and prospectus delivery requirements of the Securities Act in connection with a secondary resale transaction and that such a secondary resale transaction should be covered by an effective registration statement containing the selling security holder information required by Item 507 or 508, as applicable, of Regulation S-K if the resales are of Exchange Securities obtained by such Holder in exchange for Initial Securities acquired by such Holder directly from the Issuers.

(b) Shelf Registration Statement. In connection with the Shelf Registration Statement, each of the Issuers and the Guarantors shall comply with all the provisions of Section 6(c) hereof and shall use its commercially reasonable efforts to effect such registration to permit the sale of the Transfer Restricted Securities being sold in accordance with the intended method or methods of distribution thereof, and pursuant thereto each of the Issuers and the Guarantors will expeditiously prepare and file with the Commission a Registration Statement relating to the registration on any appropriate form under the Securities Act, which form shall be available for the sale of the Transfer Restricted Securities in accordance with the intended method or methods of distribution thereof.

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(c) General Provisions. In connection with any Registration Statement and any Prospectus required by this Agreement to permit the sale or resale of Transfer Restricted Securities (including, without limitation, any Registration Statement and the related Prospectus required to permit resales of Initial Securities by Broker-Dealers), each of the Issuers and the Guarantors shall:

(i) use its commercially reasonable efforts to keep such Registration Statement continuously effective and provide all requisite financial statements (including, if required by the Securities Act or any regulation thereunder, financial statements of the Guarantors for the period specified in Section 3 or 4 hereof, as applicable; upon the occurrence of any event that would cause any such Registration Statement or the Prospectus contained therein (A) to contain a material misstatement or omission or (B) not to be effective and usable for resale of Transfer Restricted Securities during the period required by this Agreement, the Issuers shall file promptly an appropriate amendment to such Registration Statement, in the case of clause (A), correcting any such misstatement or omission, and, in the case of either clause (A) or (B), use its commercially reasonable efforts to cause such amendment to be declared effective as soon as practicable thereafter;

(ii) prepare and file with the Commission such amendments and post-effective amendments to the applicable Registration Statement as may be necessary to keep the Registration Statement effective for the applicable period set forth in Section 3 or 4 hereof, as applicable, or such shorter period as will terminate when all Transfer Restricted Securities covered by such Registration Statement have been sold; cause the Prospectus to be supplemented by any required Prospectus supplement, and as so supplemented to be filed pursuant to Rule 424 under the Securities Act, and to comply fully with the applicable provisions of Rules 424 and 430A under the Securities Act in a timely manner; and comply with the provisions of the Securities Act with respect to the disposition of all securities covered by such Registration Statement during the applicable period in accordance with the intended method or methods of distribution by the sellers thereof set forth in such Registration Statement or supplement to the Prospectus;

(iii) advise selling Holders promptly and, if requested by such Persons, to confirm such advice in writing, (A) when the Prospectus or any Prospectus supplement or post-effective amendment has been filed, and, with respect to any applicable Registration Statement or any post-effective amendment thereto, when the same has become effective, (B) of any request by the Commission for amendments to the Registration Statement or amendments or supplements to the Prospectus or for additional information relating thereto, (C) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement under the Securities Act or of the suspension by any state securities commission of the qualification of the Transfer Restricted Securities for offering or sale in any jurisdiction, or the initiation of any proceeding for any of the preceding purposes, (D) of the existence of any fact or the happening of any event that makes any statement of a material fact made in the Registration Statement, the Prospectus, any amendment or supplement thereto, or any document incorporated by reference therein untrue, or that requires the making of any additions to or changes in the Registration Statement or the Prospectus in order to make the statements therein not misleading. If at any time the Commission shall issue any stop order suspending the effectiveness of

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the Registration Statement, or any state securities commission or other regulatory authority shall issue an order suspending the qualification or exemption from qualification of the Transfer Restricted Securities under state securities or blue sky laws, each of the Issuers and the Guarantors shall use its commercially reasonable efforts to obtain the withdrawal or lifting of such order at the earliest possible time;

(iv) furnish without charge to each of the Initial Purchasers and each selling Holder named in any Registration Statement before filing with the Commission, copies of any Registration Statement or any Prospectus included therein or any amendments or supplements to any such Registration Statement or Prospectus (including all documents incorporated by reference after the initial filing of such Registration Statement), which documents will be subject to the review and comment of such Holders in connection with such sale, if any, for a period of at least five Business Days, and the Issuers will not file any such Registration Statement or Prospectus or any amendment or supplement to any such Registration Statement or Prospectus (including all such documents incorporated by reference) to which an Initial Purchaser of Transfer Restricted Securities covered by such Registration Statement shall reasonably object in writing within five Business Days after the receipt thereof (such objection to be deemed timely made upon confirmation of telecopy transmission within such period). The objection of an Initial Purchaser shall be deemed to be reasonable if such Registration Statement, amendment, Prospectus or supplement, as applicable, as proposed to be filed, contains a material misstatement or omission;

(v) promptly prior to the filing of any document that is to be incorporated by reference into a Registration Statement or Prospectus in connection with such exchange or sale, provide copies of such document to the Initial Purchasers and each selling Holder named in any Registration Statement make the Issuers’ and the Guarantors’ representatives available for discussion of such document and other customary due diligence matters, and include such information in such document prior to the filing thereof as such selling Holders or underwriter(s), if any, reasonably may request;

(vi) make available at reasonable times for inspection by the Initial Purchasers participating in any disposition pursuant to such Registration Statement and any attorney or accountant retained by such Initial Purchasers all financial and other records, pertinent corporate documents of each of the Issuers and the Guarantors reasonably requested by such Persons and cause the Issuers’ and the Guarantors’ officers, directors and employees to supply all information reasonably requested by any such Holder, attorney or accountant in connection with such Registration Statement or any post-effective amendment thereto subsequent to the filing thereof and prior to its effectiveness;

(vii) if requested by any selling Holders, promptly incorporate in any Registration Statement or Prospectus, pursuant to a supplement or post-effective amendment if necessary, such information as such selling Holders may reasonably request to have included therein, including, without limitation, information relating to the “Plan of Distribution” of the Transfer Restricted Securities, information with respect to the principal amount of Transfer Restricted Securities being sold, the purchase price being paid therefor and any other terms of the offering of the Transfer Restricted Securities to be sold in

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such offering; and make all required filings of such Prospectus supplement or post-effective amendment as soon as practicable after the Issuers are notified of the matters to be incorporated in such Prospectus supplement or post-effective amendment;

(viii) use its commercially reasonable efforts to cause the Transfer Restricted Securities covered by the Registration Statement to be rated with the appropriate rating agencies, if so requested by the Holders of a majority in aggregate principal amount of Securities covered thereby;

(ix) if such documents are not publicly available, furnish to each Initial Purchaser and each selling Holder without charge, at least one copy of the Registration Statement, as first filed with the Commission, and of each amendment thereto, including financial statements and schedules (without documents incorporated by reference therein or exhibits thereto, unless requested);

(x) deliver to each selling Holder without charge, as many copies of the Prospectus (including each preliminary prospectus) and any amendment or supplement thereto as such Persons reasonably may request; each of the Issuers and the Guarantors hereby consent to the use of the Prospectus and any amendment or supplement thereto by each of the selling Holders in connection with the offering and the sale of the Transfer Restricted Securities covered by the Prospectus or any amendment or supplement thereto;

(xi) prior to any public offering of Transfer Restricted Securities, use its commercially reasonable efforts to cooperate with the selling Holders and their counsel in connection with the registration and qualification of the Transfer Restricted Securities under the state securities or blue sky laws of such jurisdictions as the selling Holders may reasonably request; provided, however, that none of the Issuers or the Guarantors shall be required to register or qualify as a foreign corporation where it is not then so qualified or to take any action that would subject it to the service of process in suits or to taxation, other than as to matters and transactions relating to the Registration Statement, in any jurisdiction where it is not then so subject;

(xii) cooperate with the selling Holders to facilitate the timely preparation and delivery of certificates representing Transfer Restricted Securities to be sold and not bearing any restrictive legends; and enable such Transfer Restricted Securities to be in such denominations and registered in such names as the Holders may request at least two Business Days prior to any sale of Transfer Restricted Securities made by such Holders;

(xiii) use its commercially reasonable efforts to cause the Transfer Restricted Securities covered by the Registration Statement to be registered with or approved by such other governmental agencies or authorities as may be necessary to enable the seller or sellers thereof to Consummate the disposition of such Transfer Restricted Securities, subject to the proviso contained in Section 6(c)(xi) hereof;

(xiv) if any fact or event contemplated by Section 6(c)(iii)(D) hereof shall exist or have occurred, prepare a supplement or post-effective amendment to the Registration Statement or related Prospectus or any document incorporated therein by reference or file

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any other required document so that, as thereafter delivered to the purchasers of Transfer Restricted Securities, the Prospectus will not contain an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in light of circumstances under which they were made, not misleading;

(xv) provide a CUSIP number for all Securities not later than the effective date of the Registration Statement covering such Securities and provide the Trustee under the Indenture with printed certificates for such Securities which are in a form eligible for deposit with the Depository Trust Company and take all other action necessary to ensure that all such Securities are eligible for deposit with the Depository Trust Company;

(xvi) otherwise use its commercially reasonable efforts to comply with all applicable rules and regulations of the Commission, and make generally available to its security holders, as soon as practicable, a consolidated earnings statement meeting the requirements of Rule 158 (which need not be audited) for the twelve-month period beginning with the first month of each Issuer’s first fiscal quarter commencing after the effective date of the Registration Statement;

(xvii) cause the Indenture to be qualified under the Trust Indenture Act not later than the effective date of the first Registration Statement required by this Agreement, and, in connection therewith, cooperate with the Trustee and the Holders of Securities to effect such changes to the Indenture as may be required for such Indenture to be so qualified in accordance with the terms of the Trust Indenture Act; and to execute and use its commercially reasonable efforts to cause the Trustee to execute, all documents that may be required to effect such changes and all other forms and documents required to be filed with the Commission to enable such Indenture to be so qualified in a timely manner;

(xviii) cause all Securities covered by the Registration Statement to be listed on each securities exchange or automated quotation system on which similar securities issued by the Issuers are then listed if reasonably requested by the Holders of a majority in aggregate principal amount of Initial Securities; and

(xix) provide promptly to each Holder upon request each document filed with the Commission pursuant to the requirements of Sections 13 and 15 of the Exchange Act, unless such documents are publicly available.

Each Holder agrees by acquisition of a Transfer Restricted Security that, upon receipt of any notice from the Issuers of (i) the existence of any fact of the kind described in Section 6(c)(iii)(D) hereof or (ii) the commencement of a Suspension Period, such Holder will forthwith discontinue disposition of Transfer Restricted Securities pursuant to the applicable Registration Statement until such Holder’s receipt of the copies of the supplemented or amended Prospectus contemplated by Section 6(c)(xvi) hereof, or until it is advised in writing (the “Advice”) by the Issuers that the use of the Prospectus may be resumed, and has received copies of any additional or supplemental filings that are incorporated by reference in the Prospectus. If so directed by the Issuers, each Holder will deliver to the Issuers (at the Issuers’ expense) all copies, other than permanent file copies then in such Holder’s possession, of the Prospectus covering such Transfer Restricted Securities that was current at the time of receipt of such notice. In the event the Issuers

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shall give any such notice, the time period regarding the effectiveness of such Registration Statement set forth in Section 3 or 4 hereof, as applicable, shall be extended by the number of days during the period from and including the date of the giving of such notice pursuant to Section 6(c)(iii)(D) hereof to and including the date when each selling Holder covered by such Registration Statement shall have received the copies of the supplemented or amended Prospectus contemplated by Section 6(c)(xvi) hereof or shall have received the Advice; provided, however, that no such extension shall be taken into account in determining whether Additional Interest is due pursuant to Section 5 hereof or the amount of such Additional Interest, it being agreed that the Issuers’ option to suspend use of a Registration Statement pursuant to this paragraph, other than during a Suspension Period, shall be treated as a Registration Default for purposes of Section 5 hereof.

SECTION 7. Registration Expenses.

(a) All expenses incident to the Issuers’ and the Guarantor’s performance of or compliance with this Agreement will be borne by the Issuers and the Guarantors, jointly and severally, regardless of whether a Registration Statement becomes effective, including, without limitation: (i) all registration and filing fees and expenses (including filings made by any Initial Purchaser or Holder with FINRA; (ii) all fees and expenses of compliance with federal securities and state securities or blue sky laws; (iii) all expenses of printing (including printing certificates for the Exchange Securities to be issued in the Exchange Offer and printing of Prospectuses), messenger and delivery services and telephone; (iv) all fees and disbursements of counsel for the Issuers, the Guarantors and, subject to Section 7(b) hereof, the Holders of Transfer Restricted Securities; (v) all application and filing fees in connection with listing the Exchange Securities on a securities exchange or automated quotation system pursuant to the requirements thereof; and (vi) all fees and disbursements of independent certified public accountants of the Issuers and the Guarantors (including the expenses of any special audit and comfort letters required by or incident to such performance).

Each of the Issuers and the Guarantors will, in any event, bear its internal expenses (including, without limitation, all salaries and expenses of its officers and employees performing legal or accounting duties), the expenses of any annual audit and the fees and expenses of any Person, including special experts, retained by the Issuers or the Guarantors.

(b) In connection with any Registration Statement required by this Agreement (including, without limitation, the Exchange Offer Registration Statement), the Issuers and the Guarantors, jointly and severally, will reimburse the Initial Purchasers and the Holders of Transfer Restricted Securities being tendered in the Exchange Offer and/or resold pursuant to the “Plan of Distribution” contained in the Exchange Offer Registration Statement or registered pursuant to the Shelf Registration Statement, as applicable, for the reasonable and documented fees and disbursements of not more than one counsel, who shall be Xxxxxx Xxxxxx & Xxxxxxx LLP or such other counsel as may be chosen by the Holders of a majority in principal amount of the Transfer Restricted Securities for whose benefit such Registration Statement is being prepared.

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SECTION 8. Indemnification.

(a) The Issuers and the Guarantors, jointly and severally, agree to indemnify and hold harmless (i) each Holder and (ii) each Person, if any, who controls (within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) any Holder (any of the Persons referred to in this clause (ii) being hereinafter referred to as a “controlling person”) and (iii) the respective officers and directors of any Holder or any controlling person (any Person referred to in clause (i), (ii) or (iii) may hereinafter be referred to as an “Indemnified Holder”), to the fullest extent lawful, from and against any and all losses, claims, damages, liabilities, judgments, actions and expenses (including, without limitation, and as incurred, reimbursement of all reasonable costs of investigating, preparing, pursuing, settling, compromising, paying or defending any claim or action, or any investigation or proceeding by any governmental agency or body, commenced or threatened, including the reasonable fees and expenses of counsel to any Indemnified Holder), joint or several, directly or indirectly caused by, related to, based upon, arising out of or in connection with any untrue statement or alleged untrue statement of a material fact contained in any Registration Statement or Prospectus (or any amendment or supplement thereto), or any omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading, except insofar as such losses, claims, damages, liabilities or expenses are caused by an untrue statement or omission or alleged untrue statement or omission that is made in reliance upon and in conformity with information relating to any of the Holders furnished in writing to the Issuers by any of the Holders, its directors, officers or controlling persons expressly for use therein. This indemnity agreement shall be in addition to any liability which the Issuers or any of the Guarantors may otherwise have.

In case any action or proceeding (including any governmental or regulatory investigation or proceeding) shall be brought or asserted against any of the Indemnified Holders with respect to which indemnity may be sought against the Issuers or the Guarantors, such Indemnified Holder (or the Indemnified Holder controlled by such controlling person) shall promptly notify the Issuers and the Guarantors in writing; provided, however, that the failure to give such notice shall not relieve any of the Issuers or the Guarantors of its respective obligations pursuant to this Agreement. Such Indemnified Holder shall have the right to employ its own counsel in any such action and the fees and expenses of such counsel shall be paid, as incurred, by the Issuers and the Guarantors (regardless of whether it is ultimately determined that an Indemnified Holder is not entitled to indemnification hereunder). The Issuers and the Guarantors shall not, in connection with any one such action or proceeding or separate but substantially similar or related actions or proceedings in the same jurisdiction arising out of the same general allegations or circumstances, be liable for the reasonable fees and expenses of more than one separate firm of attorneys (in addition to any local counsel) at any time for such Indemnified Holders, which firm shall be designated by the Holders. The Issuers and the Guarantors shall be liable for any settlement of any such action or proceeding effected with the Issuers’ and the Guarantors’ prior written consent, which consent shall not be withheld unreasonably, and each of the Issuers and the Guarantors agrees to indemnify and hold harmless any Indemnified Holder from and against any loss, claim, damage, liability or expense by reason of any settlement of any action effected with the written consent of the Issuers and the Guarantors. The Issuers and the Guarantors shall not, without the prior written consent of each Indemnified Holder, settle or compromise or consent to the entry of judgment in or otherwise seek to terminate any pending or threatened action, claim, litigation or

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proceeding in respect of which indemnification or contribution may be sought hereunder (whether or not any Indemnified Holder is a party thereto), unless such settlement, compromise, consent or termination includes an unconditional release of each Indemnified Holder from all liability arising out of such action, claim, litigation or proceeding.

(b) Each Holder of Transfer Restricted Securities agrees, severally and not jointly, to indemnify and hold harmless the Issuers, the Guarantors and their respective directors, officers and employees of the Issuers and the Guarantors who sign a Registration Statement, and any Person controlling (within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) the Issuers or any of the Guarantors, and the respective officers, directors, partners, employees, representatives and agents of each such Person, to the same extent as the foregoing indemnity from the Issuers and the Guarantors to each of the Indemnified Holders, but only with respect to claims and actions based on information relating to such Holder furnished in writing by such Holder expressly for use in any Registration Statement. In case any action or proceeding shall be brought against the Issuers, the Guarantors or their respective directors or officers or any such controlling person in respect of which indemnity may be sought against a Holder of Transfer Restricted Securities, such Holder shall have the rights and duties given the Issuers and the Guarantors, and the Issuers, the Guarantors, their respective directors and officers and such controlling person shall have the rights and duties given to each Holder by the preceding paragraph.

(c) If the indemnification provided for in this Section 8 is unavailable to an indemnified party under Section 8(a) or (b) hereof (other than by reason of exceptions provided in those Sections) in respect of any losses, claims, damages, liabilities, judgments, actions or expenses referred to therein, then each applicable indemnifying party, in lieu of indemnifying such indemnified party, shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages, liabilities or expenses in such proportion as is appropriate to reflect the relative benefits received by the Issuers and the Guarantors, on the one hand, and the Holders, on the other hand, from the Initial Placement (which in the case of the Issuers and the Guarantors shall be deemed to be equal to the total gross proceeds to the Issuers and the Guarantors from the Initial Placement), the amount of Additional Interest which did not become payable as a result of the filing of the Registration Statement resulting in such losses, claims, damages, liabilities, judgments actions or expenses, and such Registration Statement, or if such allocation is not permitted by applicable law, the relative fault of the Issuers and the Guarantors, on the one hand, and the Indemnified Holders, on the other hand, in connection with the statements or omissions which resulted in such losses, claims, damages, liabilities or expenses, as well as any other relevant equitable considerations. The relative fault of the Issuers on the one hand and of the Indemnified Holder on the other hand shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Issuers or any of the Guarantors, on the one hand, or the Indemnified Holders, on the other hand, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The amount paid or payable by a party as a result of the losses, claims, damages, liabilities and expenses referred to above shall be deemed to include, subject to the limitations set forth in the second paragraph of Section 8(a) hereof, any legal or other fees or expenses reasonably incurred by such party in connection with investigating or defending any action or claim.

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The Issuers, the Guarantors and each Holder of Transfer Restricted Securities agree that it would not be just and equitable if contribution pursuant to this Section 8(c) were determined by pro rata allocation (even if the Holders were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to in the immediately preceding paragraph. The amount paid or payable by an indemnified party as a result of the losses, claims, damages, liabilities or expenses referred to in the immediately preceding paragraph shall be deemed to include, subject to the limitations set forth above, any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any such action or claim. Notwithstanding the provisions of this Xxxxxxx 0, xxxx of the Holders (and its related Indemnified Holders) shall be required to contribute, in the aggregate, any amount in excess of the amount by which the total discount received by such Holder with respect to the Initial Securities exceeds the amount of any damages which such Holder has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No Person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any Person who was not guilty of such fraudulent misrepresentation. The Holders’ obligations to contribute pursuant to this Section 8(c) are several in proportion to the respective principal amount of Initial Securities held by each of the Holders hereunder and not joint.

SECTION 9. Rule 144A. Each of the Issuers and the Guarantors hereby agrees with each Holder, for so long as any Transfer Restricted Securities remain outstanding, to make available to any Holder or beneficial owner of Transfer Restricted Securities in connection with any sale thereof and any prospective purchaser of such Transfer Restricted Securities from such Holder or beneficial owner, the information required by Rule 144A(d)(4) under the Securities Act in order to permit resales of such Transfer Restricted Securities pursuant to Rule 144A under the Securities Act.

SECTION 10. [Reserved].

SECTION 11. [Reserved].

SECTION 12. Miscellaneous.

(a) Remedies. Each of the Issuers and the Guarantors hereby agrees that monetary damages would not be adequate compensation for any loss incurred by reason of a breach by it of the provisions of this Agreement and hereby agree to waive the defense in any action for specific performance that a remedy at law would be adequate.

(b) No Inconsistent Agreements. Each of the Issuers and the Guarantors will not on or after the date of this Agreement enter into any agreement with respect to its securities that would prevent consummation of the Exchange Offer or the performance by the Issuers or the Guarantors of their obligations hereunder or otherwise conflicts with the provisions hereof. Neither the Issuers nor any of the Guarantors has previously entered into any agreement granting any registration rights with respect to the Initial Securities to any Person. The rights granted to the Holders hereunder do not in any way conflict with and are not inconsistent with the rights granted to the holders of the Issuers’ or any of the Guarantors’ securities under any agreement in effect on the date hereof.

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(c) Adjustments Affecting the Securities. The Issuers will not take any action, or permit any change to occur, with respect to the Securities that would materially and adversely affect the ability of the Holders to Consummate any Exchange Offer.

(d) Amendments and Waivers. The provisions of this Agreement may not be amended, modified or supplemented, and waivers or consents to or departures from the provisions hereof may not be given unless the Issuers have (i) in the case of Section 5 hereof and this Section 12(d)(i), obtained the written consent of Holders of all outstanding Transfer Restricted Securities and (ii) in the case of all other provisions hereof, obtained the written consent of Holders of a majority of the outstanding principal amount of Transfer Restricted Securities (excluding any Transfer Restricted Securities held by the Issuers or their Affiliates). Notwithstanding the foregoing, a waiver or consent to depart from the provisions hereof that relates exclusively to the rights of Holders whose securities are being tendered pursuant to the Exchange Offer and that does not affect directly or indirectly the rights of other Holders whose securities are not being tendered pursuant to such Exchange Offer may be given by the Holders of a majority of the outstanding principal amount of Transfer Restricted Securities being tendered or registered; provided, however, that, with respect to any matter that directly or indirectly affects the rights of any Initial Purchaser hereunder, the Issuers shall obtain the written consent of each such Initial Purchaser with respect to which such amendment, qualification, supplement, waiver, consent or departure is to be effective. The provisions relating to meetings of Holders contained at Articles 86 to 94-8 of the Luxembourg Act on commercial companies of 10 August 1915, as amended, shall not apply in respect of the Initial Notes.

(e) Notices. All notices and other communications provided for or permitted hereunder shall be made in writing by hand-delivery, first-class mail (registered or certified, return receipt requested), telex, telecopier, or air courier guaranteeing overnight delivery:

(i) if to a Holder, at the address set forth on the records of the Registrar under the Indenture, with a copy to the Registrar under the Indenture; and

(ii) if to the Company or Trinseo Finance:

Trinseo Materials Operating S.C.A.

Attention: its general partner

Fax: x000 00 00 00 00

9A, rue Xxxxxxx Xxxxxxxx, X-0000 Xxxxxxxx

Xxxxx Xxxxx xx Xxxxxxxxxx

Trinseo Materials Finance, Inc.

c/o Trinseo S.A.

Attention: Xxxxxx X. Xxxx

Fax: (000) 000-0000

0000 Xxxxxxxxxxxx Xxxxxxxxx

Xxxxx 000

Xxxxxx, Xxxxxxxxxxxx 00000

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With a copy to:

Xxxxxxxx & Xxxxx LLP

000 Xxxxxxxxx Xxxxxx

Xxx Xxxx, Xxx Xxxx 00000

Telecopier No.: (000) 000-0000

Attention: Xxxxxx X. Xxxxx

Trinseo S.A.

Attention: its board of directors

Fax: x000 00 00 00 00

9A, rue Xxxxxxx Xxxxxxxx, X-0000 Xxxxxxxx

Xxxxx Xxxxx xx Xxxxxxxxxx

With copy to:

Trinseo S.A.

Attention: Xxxxxx X. Xxxx

Fax: (000) 000-0000

0000 Xxxxxxxxxxxx Xxxxxxxxx

Xxxxx 000

Xxxxxx, Xxxxxxxxxxxx 00000

All such notices and communications shall be deemed to have been duly given: at the time delivered by hand, if personally delivered; five Business Days after being deposited in the mail, postage prepaid, if mailed; when answered back, if telexed; when receipt acknowledged, if telecopied; and on the next Business Day, if timely delivered to an air courier guaranteeing overnight delivery.

Copies of all such notices, demands or other communications shall be concurrently delivered by the Person giving the same to the Trustee at the address specified in the Indenture.

(f) Successors and Assigns. This Agreement shall inure to the benefit of and be binding upon the successors and assigns of each of the parties, including, without limitation, and without the need for an express assignment, subsequent Holders of Transfer Restricted Securities; provided, however, that this Agreement shall not inure to the benefit of or be binding upon a successor or assign of a Holder unless and to the extent such successor or assign acquired Transfer Restricted Securities from such Holder. Nothing herein shall be deemed to permit any assignment, transfer or other disposition of Transfer Restricted Securities in violation of the Purchase Agreement or the Indenture.

(g) Counterparts. This Agreement may be executed in any number of counterparts and by the parties hereto in separate counterparts, each of which when so executed shall be deemed to be an original and all of which taken together shall constitute one and the same agreement.

(h) Headings. The headings in this Agreement are for convenience of reference only and shall not limit or otherwise affect the meaning hereof.

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(i) Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO CONFLICT OF LAWS.

(j) Severability. In the event that any one or more of the provisions contained herein, or the application thereof in any circumstance, is held invalid, illegal or unenforceable, the validity, legality and enforceability of any such provision in every other respect and of the remaining provisions contained herein shall not be affected or impaired thereby.

(k) Jurisdiction. The Issuers consent to the exclusive jurisdiction of the United States District Court for the Southern District of New York and any appellate court from thereof. Each of the Issuers and the Guarantors appoint CT Corporation System, located at 000 Xxxxxx Xxxxxx, 00xx Xxxxx, Xxx Xxxx, Xxx Xxxx as its authorized agent upon which service of process may be served in any action or proceeding brought in the United States District Court for the Southern District of New York or any U.S. Federal court sitting in The City of New York in connection with this Agreement.

(l) Waiver of Immunities. To the extent that the Issuers may in any jurisdiction claim for itself or its assets immunity from a suit, execution, attachment, whether in aid of execution, before judgment or otherwise, or other legal process in connection with and as set out in this Agreement and to the extent that in any jurisdiction there may be immunity attributed to the Issuers or the Issuers’ assets, whether or not claimed, the Issuers hereby irrevocably agree for the benefit of the Initial Purchasers not to claim, and irrevocably waive, the immunity to the full extent permitted by law.

(m) Currency Rate Indemnity. The Issuers agree that, if a judgment or order made by any court for the payment of any amount in respect of any Initial Notes is expressed in a currency other than U.S. dollars, the Issuers will indemnify the Initial Purchasers against any deficiency arising from any variation in rates of exchange between the date as of which the U.S. dollars currency is notionally converted into the judgment currency for the purposes of the judgment or order and the date of actual payment. This indemnity constitutes a separate and independent obligation from the Issuers’ other obligations under this Agreement, gives rise to a separate and independent cause of action, applies irrespective of any indulgence granted from time to time and will continue in full force and effect notwithstanding any judgment or order for a liquidated sum or sums in respect of amounts due under this Agreement.

(n) Entire Agreement. This Agreement is intended by the parties as a final expression of their agreement and intended to be a complete and exclusive statement of the agreement and understanding of the parties hereto in respect of the subject matter contained herein. There are no restrictions, promises, warranties or undertakings, other than those set forth or referred to herein with respect to the registration rights granted by the Issuers with respect to the Transfer Restricted Securities. This Agreement supersedes all prior agreements and understandings between the parties with respect to such subject matter.

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IN WITNESS WHEREOF, the parties have executed this Agreement as of the date first written above.

TRINSEO MATERIALS OPERATING S.C.A.
acting through its general partner Trinseo Materials S.à.x.x.
By:
		Name:		Xxxx X. Xxxxxx
		Title:		Chief Financial Officer and authorized signatory
TRINSEO MATERIALS FINANCE, INC.
By:
		Name:		Xxxx X. Xxxxxx
		Title:		Chief Financial Officer
XXXXXX LLC
By:
		Name:		Xxxx X. Xxxxxx
		Title:		Executive Vice President and Chief Financial Officer
XXXXXX US HOLDING, INC.
By:
		Name:		Xxxx X. Xxxxxx
		Title:		Executive Vice President and Chief Financial Officer

[Signature Page to the Registration Rights Agreement]

The foregoing Registration Rights Agreement is hereby confirmed and accepted as of the date first above written:

DEUTSCHE BANK SECURITIES INC.
By:
		Name:		Xxxxxxxxxxx Xxxx
		Title:		Managing Director
By:
		Name:		Xxxxxxx Merchant
		Title:		Director

[Signature Page to Reg Rights Agreement]

Exhibit A

Joinder Agreement

Trinseo Materials Operating S.C.A.

Trinseo Materials Finance, Inc.

$1,325,000,000 of 8.75% Senior Secured Notes due 2019

WHEREAS, Trinseo Materials Operating S.C.A., a société en commandite par actions (“partnership limited by shares”) organized and existing under the laws of the Grand Duchy of Luxembourg, having its registered office at 0X, xxx Xxxxxxx Xxxxxxxx, X-0000 Xxxxxxxx and registered in the Luxembourg Trade and Companies Register under number B153586 and Trinseo Materials Finance, Inc., a Delaware corporation, (each a “Company” and together, the “Companies”), the guarantors party thereto (the “Initial Guarantors”) and Deutsche Bank Securities Inc. (the “Purchaser”) heretofore executed and delivered a Registration Rights Agreement, dated January 29, 2013 (the “Registration Rights Agreement”), providing for the registration of notes substantially similar to the Initial Notes (as defined therein); and

WHEREAS, in connection therewith, each guarantor that was originally not a party thereto (the “Post-Closing Guarantors” and, together with the Initial Guarantors, the “Guarantors”) have agreed to join in the Registration Rights Agreement (as defined in the Purchase Agreement).

Capitalized terms used herein and not otherwise defined herein shall have the meanings ascribed to such terms in the Registration Rights Agreement.

NOW, THEREFORE, the undersigned Post-Closing Guarantors hereby agree for the benefit of the Purchaser, as follows:

1. Joinder. Each of the undersigned hereby acknowledges that it has received and reviewed a copy of the Registration Rights Agreement and all other documents it deems fit to enter into this Joinder Agreement (this “Joinder Agreement”), and acknowledges and agrees to (i) join and become a party to the Registration Rights Agreement as indicated by its signature below; (ii) be bound by all covenants, agreements, representations, warranties and acknowledgments applicable to a Guarantor in the Registration Rights Agreement as if made by, and with respect to, each signatory hereto as of the date of the Registration Rights Agreement; and (iii) perform all obligations and duties required and be entitled to all the benefits of a Guarantor pursuant to the Registration Rights Agreement.

[Language required under the laws of the jurisdiction of such Post-Closing Guarantor at time of execution of this Joinder Agreement.]

2. Due Authorization, Execution and Delivery. Each of the undersigned Post-Closing Guarantors hereby represents and warrants to and agrees with the Purchaser that this Joinder Agreement has been duly authorized, executed and delivered by each of them.

3. Counterparts. This Joinder Agreement may be executed in various counterparts (which may be delivered in original form or facsimile or “pdf” file thereof) that together shall constitute one and the same instrument.

4. Amendments. No amendment or waiver of any provision of this Joinder Agreement, nor any consent or approval to any departure therefrom, shall in any event be effective unless the same shall be in writing and signed by the parties to the Registration Rights Agreement.

5. Headings. The section headings used herein are for convenience only and shall not affect the construction hereof.

6. CONSTRUCTION. THE VALIDITY AND INTERPRETATION OF THIS JOINDER AGREEMENT, AND THE TERMS AND CONDITIONS SET FORTH HEREIN SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK APPLICABLE TO CONTRACTS MADE AND TO BE PERFORMED WHOLLY THEREIN, WITHOUT GIVING EFFECT TO ANY PROVISIONS THEREOF RELATING TO CONFLICTS OF LAW

[Intentionally Blank]

2

IN WITNESS WHEREOF, the undersigned has executed this Joinder Agreement this      day of             , 2013.

[                                         ]

By:

Name:

Title:

Accepted:             , 2013

DEUTSCHE BANK SECURITIES INC.

By:

Name:

Title:

By:

Name:

Title: