Underwriting Agreement

Exhibit 1.1

3,100,000 Shares*

CASELLA WASTE SYSTEMS, INC.

Class A Common Stock

UNDERWRITING AGREEMENT

St. Petersburg, Florida

January 22, 2019

Raymond James & Associates, Inc.

As Representative of the Several Underwriters

      listed on Schedule I hereto

880 Carillon Parkway

St. Petersburg, Florida 33716

Ladies and Gentlemen:

Casella Waste Systems, Inc., a Delaware corporation (the “Company”), proposes, subject to the terms and conditions stated herein, to issue and sell to the several Underwriters named in Schedule I hereto (the “Underwriters”), an aggregate of 3,100,000 shares of its Class A Common Stock, par value $0.01 per share (the “Class A Common Stock”). The aggregate of 3,100,000 shares to be purchased from the Company are called the “Firm Shares.” In addition, the Company has agreed to sell to the Underwriters, upon the terms and conditions stated herein, up to an additional 465,000 shares of Class A Common Stock (the “Additional Shares”). The Firm Shares and the Additional Shares are collectively referred to in this Agreement as the “Shares.” Raymond James & Associates, Inc. is acting as the representative of the several Underwriters and in such capacity is referred to in this Agreement as the “Representative.” To the extent there are no additional Underwriters listed on Schedule I hereto other than you, the term Representative as used herein shall mean you, as Underwriter, and the term Underwriters shall mean either the singular or plural as the context requires.

The Company wishes to confirm as follows its agreement with you and the other several Underwriters, on whose behalf you are acting, in connection with the several purchases of the Shares from the Company.

1. Registration Statement and Prospectus. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) in accordance with the provisions of the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Act”), a registration statement on Form S-3 (File No. 333-224788), which contains a base prospectus (the “Base Prospectus”), relating to, among other things, the Shares. Such registration statement, as amended, including the financial statements, exhibits and schedules thereto, at each time of effectiveness under the Act for purposes of Section 11 of the Act, as such section applies to the respective Underwriters (the “Effective Time”), including any required information deemed to be a part thereof at the time of effectiveness pursuant to Rule 430B under the Act or the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “Exchange Act”) is called the “Registration Statement.” Any preliminary prospectus supplement to the Base Prospectus that describes the Shares and the offering thereof and is used prior to the filing of the Prospectus is called, together with the Base Prospectus, a “Preliminary Prospectus.” The term “Prospectus” shall mean the prospectus supplement relating to the Shares, together with the Base Prospectus, that is first filed pursuant to Rule 424(b) under the Act after the date and time that this Agreement is executed and delivered by the parties hereto. For purposes of this Agreement, “free writing prospectus” has the meaning ascribed to it in Rule 405 under the Act, and “Issuer Free Writing Prospectus” shall mean each free writing prospectus prepared by or on behalf of the Company or used or referred to by the Company in connection with the offering of the Shares. “Time of Sale Information” shall mean the Preliminary Prospectus together with the Issuer Free Writing Prospectuses, if any, each identified in Schedule II hereto and the information included on Schedule V. All references in this Agreement to the Registration Statement, a Preliminary Prospectus, the Prospectus or the Time of Sale Information, or any amendments or supplements to any of the foregoing, shall be deemed to refer to and include any documents incorporated by reference therein, and shall include any copy thereof filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“EDGAR”).

Any reference in this Agreement to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Act, as of the date of the Registration Statement, such Preliminary Prospectus or the Prospectus, as the case may be, and any reference to any amendment or supplement to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date under the Exchange Act that, upon filing, are incorporated by reference therein, as required by paragraph (b) of Item 12 of Form S-3. As used herein, the term “Incorporated Documents” means the documents that at the time of filing are incorporated by reference in the Registration Statement, any Preliminary Prospectus, the Prospectus or any amendment or supplement thereto.

2. Agreements to Sell and Purchase. Upon the terms and conditions set forth herein, the Company hereby agrees to issue and sell an aggregate of 3,100,000 Firm Shares to the Underwriters. Upon the basis of the representations, warranties and agreements of the Company herein contained and subject to all the terms and conditions set forth herein, each Underwriter agrees, severally and not jointly, to purchase from the Company at a purchase price of $28.25 per Share (the “purchase price per Share”), the number of Firm Shares set forth opposite the name of such Underwriter in Schedule I hereto.

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The Company hereby also agrees to sell to the Underwriters, and, upon the basis of the representations, warranties and agreements of the Company herein contained and subject to all the terms and conditions set forth herein, the Underwriters shall have the right for 30 days from the date of the Prospectus to purchase from the Company up to 465,000 Additional Shares at the purchase price per Share for the Firm Shares. If any Additional Shares are to be purchased, each Underwriter, severally and not jointly, agrees to purchase the number of Additional Shares (subject to such adjustments as you may determine to avoid fractional shares) that bears the same proportion to the total number of Additional Shares to be purchased by the Underwriter as the number of Firm Shares set forth opposite the name of such Underwriter in Schedule I hereto bears to the total number of Firm Shares. The option to purchase Additional Shares may be exercised at any time within 30 days after the date of the Prospectus, but no more than once.

3. Terms of Public Offering. The Company has been advised by you that the Underwriters propose to make a public offering of their respective portions of the Shares as soon after this Agreement have become effective as in your judgment is advisable and initially to offer the Shares upon the terms set forth in the Prospectus.

Not later than 12:00 p.m. on the second business day following the date the Shares are released by the Underwriters for sale to the public, the Company shall deliver or cause to be delivered electronic copies of the Prospectus to the Representative.

Each Underwriter, unless it has or shall have obtained, as the case may be, the prior written consent of the Company, has not made and will not make any offer relating to the Shares that would constitute an Issuer Free Writing Prospectus or that would otherwise constitute a “free writing prospectus” required to be filed by the Company with the Commission or retained by the Company under Rule 433 under the Act.

4. Delivery of the Shares and Payment Therefor. Delivery to the Underwriters of the Firm Shares and payment therefor shall be made at the offices of Raymond James & Associates, Inc., 880 Carillon Parkway, St. Petersburg, Florida at 10:00 a.m., St. Petersburg, Florida time, on January 25, 2019, or such other place, time and date not later than the fifth business day thereafter as the Representative shall designate by notice to the Company (the time and date of such closing are called the “Closing Date”). The place of closing for the Firm Shares and the Closing Date may be varied by agreement between the Representative and the Company. The Company hereby acknowledges that circumstances under which the Representative may provide notice to postpone the Closing Date as originally scheduled include any determination by the Company or the Representative to recirculate to the public copies of an amended or supplemented Prospectus or a delay as contemplated by the provisions of Section 11 hereof.

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Delivery to the Underwriters of and payment for any Additional Shares to be purchased by the Underwriters shall be made at the offices of Raymond James & Associates, Inc., 880 Carillon Parkway, St. Petersburg, Florida, at 10:00 a.m., St. Petersburg, Florida time, on such date or dates (the “Additional Closing Date”) (which may be the same as the Closing Date, but shall in no event be earlier than the Closing Date nor earlier than two nor later than ten business days after the giving of the notice hereinafter referred to) as shall be specified in a written notice, from the Representative on behalf of the Underwriters to the Company, of the Underwriters’ determination to purchase a number, specified in such notice, of Additional Shares. Such notice may be given at any time within 30 days after the date of the Prospectus and must set forth the aggregate number of Additional Shares as to which the Underwriters are exercising the option. The place of closing for the Additional Shares and the Additional Closing Date may be varied by agreement between the Representative and the Company.

The Firm Shares and any Additional Shares to be purchased hereunder shall be delivered to the Representative on the Closing Date or the Additional Closing Date, as the case may be, against payment of the purchase price therefore by wire transfer of immediately available funds to an account specified in writing, not later than the close of business on the business day next preceding the Closing Date or the Additional Closing Date, as the case may be, by the Company. Payment for the Shares sold by the Company hereunder shall be delivered by the Representative to the Company. Delivery of the Shares shall be made through the facilities of The Depositary Trust Company unless the Representative shall otherwise instruct.

It is understood that the Representative has been authorized, for its own account and the accounts of the several Underwriters, to accept delivery of and receipt for, and make payment of the purchase price per Share for the Firm Shares and the Additional Shares, if any, that the Underwriters have agreed to purchase. Raymond James and Associates, Inc., individually and not as Representative of the Underwriters, may, but shall not be obligated to, make payment for any Shares to be purchased by any Underwriter whose funds shall not have been received by the Representative by the Closing Date or the Additional Closing Date, as the case may be, for the account of such Underwriter, but any such payment shall not relieve such Underwriter from any of its obligations under this Agreement.

5. Covenants and Agreements of the Company.

The Company covenants and agrees with the several Underwriters as follows:

(a) The Company will use its best efforts to cause the Registration Statement and any amendments thereto to become effective, if it has not already become effective, and will advise you promptly and, if requested by you, will confirm such advice in writing (i) of the time

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and date of any filing of any post-effective amendment to the Registration Statement or any amendment or supplement to any Preliminary Prospectus or the Prospectus and the time and date that any post-effective amendment to the Registration Statement becomes effective, (ii) if Rule 430A under the Act is employed, when the Prospectus has been timely filed pursuant to Rule 424(b) under the Act, (iii) of the receipt of any comments of the Commission, or any request by the Commission for amendments or supplements to the Registration Statement, any Preliminary Prospectus or the Prospectus or for additional information, (iv) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or of the suspension of qualification of the Shares for offering or sale in any jurisdiction or the initiation of any proceeding for such purposes and (v) within the period of time referred to in Section 5(h) hereof, of any change in the Company’s condition (financial or other), business, prospects, properties, net worth or results of operations, or of any event that comes to the attention of the Company that makes any statement made in the Registration Statement or the Prospectus (as then amended or supplemented) untrue in any material respect or that requires the making of any additions thereto or changes therein in order to make the statements therein (in the case of the Prospectus, in light of the circumstances under which they were made) not misleading in any material respect, or of the necessity to amend or supplement the Prospectus (as then amended or supplemented) to comply with the Act or any other law. If at any time the Commission shall issue any stop order suspending the effectiveness of the Registration Statement, the Company will make every commercially reasonable effort to obtain the withdrawal or lifting of such order at the earliest possible time. The Company will provide the Underwriters with electronic copies of the form of Prospectus, in such number as the Underwriters may reasonably request, and file with the Commission such Prospectus in accordance with Rule 424(b) under the Act before the close of business on the first business day immediately following the date hereof.

(b) If requested by you, the Company will furnish to you, without charge, two copies of the Registration Statement as originally filed with the Commission and of each amendment thereto, including financial statements and all exhibits thereto, and will also furnish to you, without charge, such number of conformed copies of the Registration Statement as originally filed and of each amendment thereto as you may reasonably request.

(c) The Company will promptly file with the Commission through the time when a prospectus relating to the Shares is required by the Act to be delivered in connection with sales of the Shares any amendment or supplement to the Registration Statement or the Prospectus that may, in the judgment of the Company or the Representative be required by the Act or requested by the Commission.

(d) The Company will furnish a copy of any amendment or supplement to the Registration Statement or to the Prospectus or any Issuer Free Writing Prospectus to you and counsel for the Underwriters and obtain your consent prior to filing any of those with the Commission through the time when a prospectus relating to the Shares is required by the Act to be delivered in connection with sales of the Shares.

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(e) The Company will not make any offer relating to the Shares that would constitute an Issuer Free Writing Prospectus without your prior consent.

(f) The Company will retain in accordance with the Act all Issuer Free Writing Prospectuses not required to be filed pursuant to the Act; and if at any time after the date hereof any events shall have occurred as a result of which any Issuer Free Writing Prospectus, as then amended or supplemented, would conflict with the information in the Registration Statement, the most recent Preliminary Prospectus or the Prospectus or would include an untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, or, if for any other reason it shall be necessary to amend or supplement any Issuer Free Writing Prospectus, to notify you and, upon your request, to file such document and to prepare and furnish without charge to each Underwriter as many copies as they may from time to time reasonably request of an amended or supplemented Issuer Free Writing Prospectus that will correct such conflict, statement or omission or effect such compliance.

(g) Promptly following the execution and delivery of this Agreement, the Company will deliver to you, without charge, in such quantities as you have requested or may hereafter reasonably request, electronic copies of each form of the Preliminary Prospectus. Consistent with the provisions of Section 5(h) hereof, the Company consents to the use, in accordance with the provisions of the Act and with the securities or Blue Sky laws of the jurisdictions in which the Shares are offered by the several Underwriters and by dealers, prior to the date of the Prospectus, of each Preliminary Prospectus so furnished by the Company.

(h) As soon after the execution and delivery of this Agreement as is practicable and thereafter from time to time for such period as in the reasonable opinion of counsel for the Underwriters a prospectus is required by the Act to be delivered in connection with sales by any Underwriter or a dealer (the “Prospectus Delivery Period”), and for so long a period as you may request for the distribution of the Shares, the Company will deliver to each Underwriter and each dealer, without charge, as many copies of the Prospectus and the Time of Sale Information (and of any amendment or supplement thereto) as they may reasonably request. The Company consents to the use of the Prospectus and the Time of Sale Information (and of any amendment or supplement thereto) in accordance with the provisions of the Act and with the securities or Blue Sky laws of the jurisdictions in which the Shares are offered by the several Underwriters and by all dealers to whom Shares may be sold, both in connection with the offering and sale of the Shares and for such period of time thereafter as the Prospectus is required by the Act to be delivered in connection with sales by any Underwriter or dealer. If at any time prior to the later of (i) the completion of the distribution of the Shares pursuant to the

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offering contemplated by the Registration Statement or (ii) the expiration of prospectus delivery requirements with respect to the Shares under Section 4(a)(3) of the Act and Rule 174 thereunder, any event shall occur that in the judgment of the Company or in the opinion of counsel for the Underwriters is required to be set forth in the Prospectus (as then amended or supplemented) or should be set forth therein in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, or if it is necessary to supplement or amend the Prospectus to comply with the Act or any other law, the Company will forthwith prepare and, subject to Section 5(a) hereof, file with the Commission and use its commercially reasonable best efforts to cause to become effective as promptly as possible an appropriate supplement or amendment thereto, and will furnish to each Underwriter who has previously requested Prospectuses, without charge, a reasonable number of copies thereof.

(i) During the Prospectus Delivery Period, the Company will file all documents required to be filed with the Commission pursuant to Sections 13, 14 and 15 of the Exchange Act in the manner and within the time periods required by the Exchange Act.

(j) The Company will cooperate with you and counsel for the Underwriters in connection with the registration or qualification of the Shares for offering and sale by the several Underwriters and by dealers under the securities or Blue Sky laws of such jurisdictions as you may reasonably designate and will file such consents to service of process or other documents as may be reasonably necessary in order to effect and maintain such registration or qualification for so long as required to complete the distribution of the Shares; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action that would subject it to general service of process in suits, other than those arising out of the offering or sale of the Shares, as contemplated by this Agreement and the Prospectus, in any jurisdiction where it is not now so subject. In the event that the qualification of the Shares in any jurisdiction is suspended, the Company shall so advise you promptly in writing. The Company will use its commercially reasonable best efforts to qualify or register its Class A Common Stock for sale in non-issuer transactions under (or obtain exemptions from the application of) the Blue Sky laws of each state where necessary to permit market making transactions and secondary trading and will comply with such Blue Sky laws and will continue such qualifications, registrations and exemptions in effect for so long as required for the distribution of the Shares, but in no event beyond one year after the date hereof.

(k) The Company will make generally available to its security holders a consolidated earning statement (in form complying with the provisions of Rule 158 under the Act), which need not be audited, covering a twelve-month period commencing after the effective date of the Registration Statement and ending not later than 15 months thereafter, as soon as practicable after the end of such period, which consolidated earning statement shall satisfy the provisions of Section 11(a) of the Act.

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(m) If this Agreement shall terminate or shall be terminated after execution pursuant to any provision hereof (except pursuant to a termination under Section 11 or Section 12 hereof, other than clauses (iv) or (v)) or if this Agreement shall be terminated by the Underwriters because of any inability, failure or refusal on the part of the Company to perform in all material respects any agreement herein or to comply in all material respects with any of the terms or provisions hereof or to fulfill in all material respects any of the conditions of this Agreement, the Company agrees to reimburse you and the other Underwriters for all reasonable and documented out-of-pocket expenses (including travel expenses and reasonable fees and expenses of counsel for the Underwriters, but excluding wages and salaries paid by you) not to exceed an aggregate of $250,000 reasonably incurred by you and the Underwriters in connection herewith.

(n) The Company will apply the net proceeds from the sale of the Shares to be sold by it hereunder in accordance in all material respects with the statements under the caption “Use of Proceeds” in the Prospectus.

(o) For a period commencing on the date hereof and ending on the day that is 30 days after the date of the Prospectus (the “Lock-Up Period”), the Company agrees not to, directly or indirectly, (1) offer for sale, sell, pledge or otherwise dispose of (or enter into any transaction or device that is designed to, or could be expected to, result in the disposition by any person at any time in the future) any shares of Class A Common Stock or securities convertible into or exchangeable for Class A Common Stock (other than the Class A Common Stock issued pursuant to employee benefit plans, qualified stock option plans or other employee compensation plans existing on the date hereof or pursuant to currently outstanding options, warrants, rights or other awards), or sell or grant options, rights or warrants with respect to any shares of Class A Common Stock or securities convertible into or exchangeable for Class A Common Stock (other than the grant of options or other awards pursuant to equity incentive plans existing on the date hereof), (2) enter into any swap or other derivatives transaction that transfers to another, in whole or in part, any of the economic benefits or risks of ownership of such shares of Class A Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Class A Common Stock or other securities, in cash or otherwise, (3) file or cause to be filed a registration statement, including any amendments, with respect to the registration of any shares of Class A Common Stock or securities convertible, exercisable or exchangeable into Class A Common Stock or any other securities of the Company (other than the filing of a registration statement on Form S-8 or a successor form thereto or (4) publicly disclose the intention to do any of the foregoing, in each case without the prior written consent of the Representative on behalf of the Underwriters, and to cause each officer and director of the Company set forth on Schedule VI hereto to furnish to the Representative, prior to the Closing Date, a letter or letters, substantially in the form of Exhibit A hereto (the “Lock-Up Agreements”). The restrictions on the Company contained in the preceding sentence shall not apply to (A) the Shares to be sold hereunder, (B) the issuance of up to 103,034 shares of Class A

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Common Stock that may be issued in connection the acquisition of Youngblood Disposal Enterprises of Western New York, LLC, (C) the issuance of shares of Class A Common Stock, restricted stock units, options to purchase Class A Common Stock or performance units pursuant to employee benefit plans, qualified stock option plans, the Company’s equity incentive plans or other employee compensation plans in effect on the date of this Agreement and that are disclosed in the Company’s public filings with the Commission and incorporated by reference in the Prospectus or pursuant to currently outstanding restricted stock units, options, warrants, rights or performance units and (D) the sale or issuance of shares of Class A Common Stock to an unaffiliated third party in connection with an acquisition, a merger, a consolidation or sale or purchase of assets or in connection with a strategic alliance, investment, partnership, collaboration, marketing arrangement or other joint venture or strategic transaction in an aggregate amount not to exceed 10% of the outstanding shares of Class A Common Stock as of the date of this Agreement, provided that prior to the issuance of any shares of Class A Common Stock pursuant to this clause (D) during the Lock-Up Period, the recipient(s) of such shares of Class A Common Stock shall sign and deliver a lock-up agreement substantially in the form of Exhibit A hereto.

(p) Prior to the Closing Date or the Additional Closing Date, as the case may be, at the reasonable request of the Underwriters, the Company will furnish to you, as promptly as possible, copies of any unaudited interim consolidated financial statements of the Company and its subsidiaries for any period subsequent to the periods covered by the financial statements appearing in the Prospectus.

(q) The Company will comply with all provisions of any undertakings contained in the Registration Statement.

(r) The Company will not at any time, directly or indirectly, take any action designed, or which might reasonably be expected to cause or result in, or which will constitute, stabilization or manipulation of the price of the shares of Class A Common Stock to facilitate the sale or resale of any of the Shares.

(s) The Company will timely file with the Nasdaq Global Select Market (“Nasdaq”) all documents and notices required by the Nasdaq of companies that have or will issue securities that are traded on the Nasdaq.

(t) The Company shall engage and maintain, at its expense, a transfer agent and, if necessary under the jurisdiction of its incorporation or the rules of any national securities exchange on which the Class A Common Stock is listed, a registrar (which, if permitted by applicable laws and rules may be the same entity as the transfer agent) for the Class A Common Stock.

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6. Representations and Warranties of the Company.

The Company hereby represents and warrants to each Underwriter on the date hereof, and shall be deemed to represent and warrant to each Underwriter on the Closing Date and the Additional Closing Date, as the case may be, that:

(a) The Company meets the requirement for use of Form S-3 under the Act. The Registration Statement is an “automatic shelf registration statement” (as defined in Rule 405 under the Act) and the Shares have been and remain eligible for registration by the Company on such automatic shelf registration statement.

(b) At the time of filing the Registration Statement and any post-effective amendment thereto, at the earliest time thereafter that the Company or any offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Act) of the Shares and at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405 under the Act. The Company has paid the registration fee for this offering pursuant to Rule 456(b)(1) under the Act or will pay such fee within the time period required by such rule (without giving effect to the proviso therein) and in any event prior to the Closing Date.

(c) The Registration Statement conformed, and any amendment to the Registration Statement filed after the date hereof will conform, in each case, in all material respects, when filed with the Commission, to the requirements of the Act. The most recent Preliminary Prospectus conformed, and the Prospectus will conform, in each case, in all material respects, when filed with the Commission, to the requirements of Rule 424(b) under the Act.

(d) The Registration Statement does not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading; provided, that no representation or warranty is made as to information contained in or omitted from the Registration Statement in reliance upon and in conformity with written information furnished to the Company through the Representative by or on behalf of any Underwriter specifically for inclusion therein.

(e) The Incorporated Documents heretofore filed, when they were filed (or, if any amendment with respect to any such document was filed, when such amendment was filed), conformed in all material respects with the requirements of the Exchange Act and the rules and regulations thereunder, and any further Incorporated Documents so filed will, when they are filed, conform in all material respects with the requirements of the Exchange Act and the rules and regulations thereunder; no such Incorporated Document when it was filed (or, if an amendment with respect to any such document was filed, when such amendment was filed), contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading; and no such further Incorporated Document, when it is filed, will contain an untrue statement of a material fact or will omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading.

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(f) The financial statements, together with the related schedules and notes, included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, comply in all material respects with the applicable requirements of the Act and Exchange Act, as applicable, and present fairly in all material respects the consolidated financial position of the entities to which they relate as of and at the dates indicated and the results of their operations and cash flows for the periods specified. Such financial statements have been prepared in conformity with generally accepted accounting principles as applied in the United States (“GAAP”) applied on a consistent basis throughout the periods involved, except for normal recurring adjustments or as may be expressly stated in the related notes thereto. The financial data set forth in the Registration Statement, the Time of Sale Information and the Prospectus fairly present in all material respects the information set forth therein on a basis consistent with that of the audited financial statements contained or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus. The statistical and market-related data and forward-looking statements included in the Registration Statement, the Time of Sale Information and the Prospectus are based on or derived from sources that the Company believes to be reliable and accurate in all material respects and represent their good faith estimates that are made on the basis of data derived from such sources. Except as included or incorporated by reference therein, no historical or pro forma financial statements or supporting schedules are required to be included or incorporated by reference in the Registration Statement, the Time of Sale Information or the Prospectus, or incorporated by reference therein, under the Act. All disclosures contained in the Registration Statement, the Time of Sale Information or the Prospectus, or incorporated by reference therein, regarding “non-GAAP financial measures” (as such term is defined by the rules and regulations of the Commission) comply in all material respects with Regulation G of the Exchange Act and Item 10 of Regulation S-K of the Act, to the extent applicable. The Prospectus will not contain an untrue statement of a material fact or omit to state a 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; provided that no representation or warranty is made as to information contained in or omitted from the Prospectus in reliance upon and in conformity with written information furnished to the Company through the Representative by or on behalf of any Underwriter specifically for inclusion therein.

(g) The Time of Sale Information does not, and will not at the time of sale of the Shares in connection with the offering by the Company, contain an untrue statement of a material fact or omit to state a 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; provided that no representation or warranty is made as to information contained in or omitted from the Time of Sale Information in reliance upon and in conformity with written information furnished to the Company through the Representative by or on behalf of any Underwriter specifically for inclusion therein.

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(h) Each Issuer Free Writing Prospectus (including, without limitation, any road show that is a free writing prospectus under Rule 433 under the Act), when considered together with the Time of Sale Information at the time of sale of the Shares in connection with the offering by the Company, did not contain an untrue statement of a material fact or omit to state a 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.

(i) Each Issuer Free Writing Prospectus conformed or will conform in all material respects to the requirements of the Act on the date of first use, and the Company has complied with all prospectus delivery and any filing requirements applicable to such Issuer Free Writing Prospectus pursuant to the Act. The Company has not made any offer relating to the Shares that would constitute an Issuer Free Writing Prospectus without the prior written consent of the Representative. The Company has retained in accordance with the Act all Issuer Free Writing Prospectuses that were not required to be filed pursuant to the Act. The Company has taken all actions necessary so that any “road show” (as defined in Rule 433 under the Act) in connection with the offering of the Shares will not be required to be filed pursuant to the Act.

(j) Except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus (exclusive of any amendment or supplement thereto), subsequent to the respective dates as of which information is given in the Registration Statement, the Time of Sale Information and the Prospectus (exclusive of any amendment or supplement thereto): (i) there has been no material adverse change, or any development that could reasonably be expected to result in a material adverse change, in the financial condition, or in the earnings, business or operations of the Company and its subsidiaries, considered as one entity (any such change is called a “Material Adverse Change”); (ii) the Company and its subsidiaries, considered as one entity, have not incurred any material liability or obligation, indirect, direct or contingent, not in the ordinary course of business nor entered into any material transaction or agreement not in the ordinary course of business which remains outstanding; and (iii) there has been no dividend or distribution of any kind declared, paid or made by the Company or, except for dividends paid to the Company or any of its subsidiaries on any class of capital stock, any repurchase or redemption by the Company or any of its subsidiaries of any class of capital stock.

(k) Each of the Company and its subsidiaries has been duly incorporated or formed, as applicable, and is validly existing as a corporation, limited partnership or limited liability company, as applicable, in good standing under the laws of the jurisdiction of its incorporation or formation, as applicable, except where the failure be in good standing would not result in a Material Adverse Change, and has corporate, partnership or limited liability company,

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as applicable, power and authority to own, lease and operate its properties and to conduct its business as described in the Registration Statement, the Time of Sale Information and the Prospectus and, in the case of the Company, to enter into and perform its obligations under this Agreement. The Company and each of its subsidiaries is duly qualified as a foreign corporation, limited partnership or limited liability company, as applicable, to transact business and, if applicable, is in good standing or equivalent status in each jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except for such jurisdictions where the failure to so qualify or to be in good standing would not, individually or in the aggregate, result in a Material Adverse Change. All of the issued and outstanding capital stock or other ownership interest of each of the Company’s subsidiaries has been duly authorized and validly issued, is fully paid and nonassessable and is owned by the Company, directly or through subsidiaries, free and clear of any security interest, mortgage, pledge, lien, encumbrance or claim except as disclosed in the Registration Statement, the Time of Sale Information and Prospectus. The entities set forth on Schedule III hereto are the only direct or indirect subsidiaries of the Company and the entities set forth on Schedule IV hereto are the only entities (other than those direct and indirect subsidiaries of the Company set forth on Schedule III) in which the Company has any direct or indirect equity or ownership interest.

(l) At September 30, 2018, on a consolidated basis, after giving pro forma effect to the issuance and sale of the Shares pursuant hereto, the Company would have an authorized and outstanding capitalization as set forth in the Time of Sale Information and the Prospectus under the caption “Capitalization” (other than for subsequent issuances of capital stock, if any, as described in the Time of Sale Information and Prospectus or upon exercise of outstanding options or the vesting of outstanding awards as described in the Time of Sale Information and Prospectus); all the outstanding shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable and are not subject to any pre-emptive or similar rights; except as described in or expressly contemplated by the Time of Sale Information and the Prospectus, there are no outstanding rights (including, without limitation, pre-emptive rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other equity interest in the Company or any of its subsidiaries, or any contract, commitment, agreement, understanding or arrangement of any kind relating to the issuance of any capital stock of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock of the Company conforms in all material respects to the description thereof contained or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus.

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(m) With respect to the stock options (the “Stock Options”) granted pursuant to the stock-based compensation plans of the Company and its subsidiaries in the past two years (the “Company Stock Plans”), (i) each grant of a Stock Option was duly authorized no later than the date on which the grant of such Stock Option was by its terms to be effective (the “Grant Date”) by all necessary corporate action, including, as applicable, approval by the Board of Directors of the Company (or a duly constituted and authorized committee thereof) and any required stockholder approval by the necessary number of votes or written consents, and the award agreement governing such grant (if any) was duly executed and delivered by each party thereto, (ii) each such grant was made in accordance with the terms of the Company Stock Plans, the Exchange Act and all other applicable laws and regulatory rules or requirements, including the rules of the Nasdaq Global Select Market and any other securities exchange on which Company securities are traded, (iii) the per share exercise price of each Stock Option was equal to the fair market value of a share of common stock on the applicable Grant Date and (iv) each such grant was properly accounted for in accordance with GAAP in the financial statements (including the related notes) of the Company and disclosed in the Company’s filings with the Commission in accordance with the Exchange Act and all other applicable laws. The Company has not deliberately granted, and there is no and has been no policy or practice of the Company of granting, Stock Options prior to, or otherwise coordinating the grant of Stock Options with, the release or other public announcement of material information regarding the Company or its subsidiaries or their results of operations or prospects.

(n) The Company has full right, power and authority to execute and deliver this Agreement and to perform its obligations hereunder; and all action required to be taken for the due and proper authorization, execution and delivery by it of this Agreement and the consummation by it of the transactions contemplated hereby has been duly and validly taken.

(o) This Agreement has been duly authorized, executed and delivered by the Company.

(p) The Shares to be issued and sold by the Company hereunder have been duly authorized and, when issued and delivered and paid for as provided herein, will be duly and validly issued, will be fully paid and nonassessable and will conform to the descriptions thereof contained or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus; and the issuance of the Shares is not subject to any preemptive or similar rights that have not been waived.

(q) This Agreement conforms in all material respects to the description thereof contained in the Registration Statement, the Time of Sale Information and the Prospectus.

(r) Neither the Company nor any of its subsidiaries is (i) in violation of its charter, bylaws, partnership agreement or limited liability company agreement or (ii) except as disclosed in the Time of Sale Information and Prospectus, in default (or, with the giving of notice or lapse of time, would be in default) (“Default”) under any indenture, mortgage, loan or credit

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agreement, note, contract, franchise, lease or other instrument to which the Company or any of its subsidiaries is a party or by which it or any of them may be bound (including, without limitation, the Company’s Credit Agreement dated as of May 14, 2018, as amended prior to the date hereof (the “Senior Credit Facility”)), or to which any of the property or assets of the Company or any of its subsidiaries is subject (each, an “Existing Instrument”), except, in the case of clause (ii) above, for such Defaults as would not, individually or in the aggregate, result in a Material Adverse Change or prevent the consummation of the transactions contemplated by this Agreement. The execution, delivery and performance of this Agreement by the Company, and the issuance and delivery of the Shares, and consummation of the transactions contemplated hereby and by the Prospectus (i) have been duly authorized by all necessary corporate action and will not result in any violation of the provisions of the charter or bylaws of the Company, (ii) will not conflict with or constitute a breach of, or result in a default or a Debt Repayment Triggering Event (as defined below) under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, or require the consent of any other party to, any Existing Instrument, except for such conflicts, breaches, Defaults, liens, charges or encumbrances as would not, individually or in the aggregate, result in a Material Adverse Change and (iii) will not result in any violation of any law, administrative regulation or administrative or court decree applicable to the Company or any of its subsidiaries, except for such violations as would not, individually or in the aggregate, result in a Material Adverse Change. As used herein, a “Debt Repayment Triggering Event” means any event or condition which gives, or with the giving of notice or lapse of time would give, the holder of any note, debenture or other evidence of indebtedness (or any person acting on such holder’s behalf) the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any of its subsidiaries.

(s) No consent, approval, authorization or other order of, or registration or filing with, any court or other governmental or regulatory authority or agency is required for the execution, delivery and performance of this Agreement by the Company, or the issuance and delivery of the Shares, or consummation of the transactions contemplated hereby and by the Time of Sale Information and the Prospectus, except (i) registration of the Shares under the Act, (ii) such consents, approvals, authorizations, orders and registrations or qualifications as may be required by the Financial Industry Regulatory Authority, Inc. (“FINRA”) and (iii) such filings as have been obtained or made by the Company and are in full force and effect under the Act, applicable securities laws of the several states of the United States.

(t) Except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, there are no legal or governmental actions, suits or proceedings pending or, to the best of the Company’s knowledge, threatened (i) against or affecting the Company or any of its subsidiaries or (ii) which has as the subject thereof any property owned or leased by, the Company or any of its subsidiaries and any such action, suit or proceeding, if determined adversely to the Company or such subsidiary, would result in a

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Material Adverse Change or adversely affect the consummation of the transactions contemplated by this Agreement; and (x) there are no current or pending legal, governmental or regulatory actions, suits or proceedings that are required under the Act to be described in the Registration Statement, the Time of Sale Information or the Prospectus that are not so described in the Registration Statement, the Time of Sale Information and the Prospectus and (y) there are no statutes, regulations or contracts or other documents that are required under the Act to be filed as exhibits to the Registration Statement or described in the Registration Statement, the Time of Sale Information or the Prospectus that are not so filed as exhibits to the Registration Statement or described in the Registration Statement, the Time of Sale Information and the Prospectus. No material labor dispute with the employees of the Company or any of its subsidiaries exists or, to the best of the Company’s knowledge, is threatened or imminent. Except as described in the Registration Statement, the Time of Sale Information and the Prospectus, no person has the right to require the Company or any of its subsidiaries to register any securities for sale under the Act by reason of the filing of the Registration Statement with the Commission or the issuance and sale of the Shares that have not been waived.

(u) RSM US LLP, which expressed its opinion with respect to the financial statements (which term as used in this Agreement includes the related notes thereto) and supporting schedules filed with the Commission and included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, is an independent registered public accounting firm within the meaning of the Act and the Exchange Act and the rules of the Public Company Accounting Oversight Board, and any non-audit services provided by RSM US LLP to the Company have been approved by the Audit Committee of the Board of Directors of the Company.

(v) The Company and each of its subsidiaries have good and marketable title to all the properties and assets reflected as owned in the financial statements referred to in Section 6(f) hereof, in each case free and clear of any security interests, mortgages, liens, encumbrances, equities, claims and other defects, except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus and except such as do not materially and adversely affect the value of such property and do not materially interfere with the use made or proposed to be made of such property by the Company or such subsidiary. The real property, improvements, equipment and personal property held under lease by the Company or any of its subsidiaries are held under valid and enforceable leases, with such exceptions as are not material and do not materially interfere with the use made or proposed to be made of such real property, improvements, equipment or personal property by the Company or such subsidiary.

(w) The Company and its subsidiaries own or possess sufficient trademarks, trade names, patent rights, copyrights, licenses, approvals, trade secrets and other similar rights (collectively, “Intellectual Property Rights”) reasonably necessary to conduct their businesses as now conducted; and the expected expiration of any of such Intellectual Property Rights would

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not result in a Material Adverse Change. Neither the Company nor any of its subsidiaries has received any notice of infringement or conflict with asserted Intellectual Property Rights of others, which infringement or conflict, if the subject of an unfavorable decision, would result in a Material Adverse Change.

(x) No relationship, direct or indirect, exists between or among any of the Company or any affiliate of the Company, on the one hand, and any director, officer, member, stockholder, customer or supplier of the Company or any affiliate of the Company, on the other hand, which is required by the Act to be disclosed in a registration statement on Form S-3 which is not so disclosed in the Registration Statement, the Time of Sale Information and the Prospectus. Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, there are no outstanding loans, advances (except advances for business expenses in the ordinary course of business or intercompany indebtedness between the Company and one of its subsidiaries) or guarantees of indebtedness by the Company or any affiliate of the Company to or for the benefit of any of the officers or directors of the Company or any affiliate of the Company or any of their respective family members.

(y) The Company has been advised of the rules and requirements under the Investment Company Act of 1940, as amended (the “Investment Company Act,” which term, as used herein, includes the rules and regulations of the Commission promulgated thereunder). The Company is not, nor after receipt of payment for the Shares will be, an “investment company” within the meaning of the Investment Company Act and will conduct its business in a manner so that it will not become an “investment company” within the meaning of the Investment Company Act.

(z) The Company and its subsidiaries have filed all necessary federal, state and foreign income and franchise tax returns and have paid all material taxes required to be paid by any of them and, if due and payable, any material related or similar assessment, fine or penalty levied against any of them except as may be being contested in good faith and by appropriate proceedings. The Company has made adequate charges, accruals and reserves in accordance with GAAP in the applicable financial statements referred to in Sections 6(f) and 6(u) hereof in respect of all federal, state and foreign income and franchise taxes for all periods as to which the tax liability of the Company or any of its subsidiaries has not been finally determined.

(aa) Except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, the Company and each of its subsidiaries possess such valid and current certificates, authorizations or permits issued by the appropriate state, federal or foreign regulatory agencies or bodies necessary to own, lease and operate its properties and to conduct their respective businesses, and neither the Company nor any of its subsidiaries has received any notice of proceedings relating to the revocation or modification of, or non-compliance with, any such certificate, authorization or permit which, singly or in the aggregate, if the subject of an unfavorable decision, ruling or finding, would result in a Material Adverse Change.

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(bb) Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus and except as would not, individually or in the aggregate, result in a Material Adverse Change, (i) there is (A) no unfair labor practice complaint pending or, to the best of the Company’s knowledge, threatened against the Company or any of its subsidiaries before the National Labor Relations Board, and no grievance or arbitration proceeding arising out of or under collective bargaining agreements pending, or to the best of the Company’s knowledge, threatened, against the Company or any of its subsidiaries, (B) no strike, labor dispute, slowdown or stoppage pending or, to the best of the Company’s knowledge, threatened against the Company or any of its subsidiaries and (C) no union representation question existing with respect to the employees of the Company or any of its subsidiaries and, to the best of the Company’s knowledge, no union organizing activities taking place and (ii) there has been no violation of any federal, state or local law relating to discrimination in hiring, promotion or pay of employees or of any applicable wage or hour laws.

(cc) Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus and except as would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Change, (A) the Company and each of its subsidiaries is in compliance with, and not subject to any known liability under, applicable Environmental Laws (as defined below), (B) the Company and each of its subsidiaries has made all filings, and provided all financial assurances and notices, required under any applicable Environmental Law, and has, and is in compliance with, all permits, approvals and authorizations required under any applicable Environmental Laws and each of them is in full force and effect, (C) there is no civil, criminal or administrative action, suit, demand, claim, hearing, written notice of violation, proceeding, notice or demand letter or written request for information pending or, to the knowledge of the Company, threatened, or, to the knowledge of the Company, investigation threatened or pending, against the Company or any of its subsidiaries under any Environmental Law, (D) no lien, charge, encumbrance or restriction has been recorded under any Environmental Law with respect to any assets, facility or property owned, operated or leased by the Company or any of its subsidiaries, (E) none of the Company or any of its subsidiaries has received notice that it has been identified as a potentially responsible party under the Comprehensive Environmental Response, Compensation and Liability Act of 1980, as amended (“CERCLA”), or any comparable state law, (F) no property or facility of the Company or any of its subsidiaries is (i) listed or, to the best knowledge of the Company, formally proposed for listing on the National Priorities List under CERCLA or (ii) listed in the Comprehensive Environmental Response, Compensation and Liability Information System List promulgated pursuant to CERCLA, or on any comparable list maintained by any state or local governmental authority, (G) neither the Company nor any of its subsidiaries is conducting, or

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paying in whole or in part for, any investigation, response or other corrective action pursuant to any Environmental Law at any site or facility, nor is any of them subject or party to any order, judgment, decree, contract or agreement which obligates it to conduct any such actions nor has any of them assumed by contract or agreement any obligation or liability under any Environmental Law, and (H) there are no past or present operations, occurrences or conditions which could reasonably be expected to prevent or interfere with compliance by the Company or any of its subsidiaries with, or result in liability of any of them under, any Environmental Law.

For purposes of this Agreement, “Environment” means ambient air, indoor air, surface water, groundwater, drinking water, soil, surface or subsurface strata, and natural resources such as wetlands, flora and fauna. “Environmental Laws” means the common law and all applicable federal, provincial, state and local laws or regulations, codes, ordinances, orders, decrees, judgments or injunctions issued, promulgated, approved or entered thereunder, relating to pollution or protection of the Environment or human health (to the extent relating to exposure to Hazardous Materials), including, without limitation, laws relating to (i) Releases or threatened Releases of Hazardous Materials into the Environment, (ii) the manufacture, processing, distribution, use, generation, treatment, storage, disposal, transport, handling or recycling of Hazardous Materials, (iii) facility siting, environmental impact assessment or review, or land use, and (iv) underground and aboveground storage tanks and related piping, and Releases or threatened Releases of Hazardous Materials therefrom. “Hazardous Materials” means any substance, material, pollutant, contaminant, chemical, constituent, compound or waste, in any form, including without limitation petroleum and petroleum products, subject to regulation or which could give rise to liability under any Environmental Law. “Release” means any release, spill, emission, discharge, leaking, pumping, pouring, dumping, emptying, injection, leaching, deposit or disposal of Hazardous Materials into the Environment, or into or out of any building.

(dd) In the ordinary course of its business, the Company reviews the effect of Environmental Laws on the business, operations and properties of the Company and its subsidiaries, in the course of which it identifies and evaluates any anticipated costs and liabilities (including, without limitation, any capital or operating expenditures required for clean-up, closure of properties or compliance with Environmental Laws or any permit, license or approval, any related constraints on operating activities and any potential liabilities to third parties). On the basis of such review, the Company has reasonably concluded that, except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, such associated costs and liabilities would not, individually or in the aggregate, result in a Material Adverse Change.

(ee) The Company and its subsidiaries and any “employee benefit plan” (as defined under the Employee Retirement Income Security Act of 1974 (as amended, “ERISA,” which term, as used herein, includes the regulations and published interpretations thereunder)) established or maintained by the Company, its subsidiaries or their “ERISA Affiliates” (as defined below) are in compliance in all material respects with ERISA and, to the knowledge of

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the Company, each “multiemployer plan” (as defined in Section 4001 of ERISA) to which the Company, its subsidiaries or an ERISA Affiliate contributes (a “Multiemployer Plan”) is in compliance in all material respects with ERISA. “ERISA Affiliate” means, with respect to the Company or its subsidiaries, any member of any group of organizations described in Section 414 of the Internal Revenue Code of 1986 (as amended, the “Code,” which term, as used herein, includes the regulations and published interpretations thereunder) of which the Company or such subsidiary is a member. No “reportable event” (as defined under ERISA) has occurred or is reasonably expected to occur with respect to any “employee benefit plan” established or maintained by the Company, its subsidiaries or any of their ERISA Affiliates. No “single employer plan” (as defined in Section 4001 of ERISA) established or maintained by the Company, its subsidiaries or any of their ERISA Affiliates, if such “employee benefit plan” were terminated, would have any “amount of unfunded benefit liabilities” (as defined under ERISA). Neither the Company, its subsidiaries nor any of their ERISA Affiliates has incurred or reasonably expects to incur any liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from, any “employee benefit plan” or (ii) Sections 412, 4971, 4975 or 4980B of the Code. Each “employee benefit plan” established or maintained by the Company, its subsidiaries or any of their ERISA Affiliates that is intended to be qualified under Section 401 of the Code is so qualified and nothing has occurred, whether by action or failure to act, which would cause the loss of such qualification.

(ff) The Company has established and maintains disclosure controls and procedures (as such term is defined in Rules 13a-15 and 15d-15 under the Exchange Act); such disclosure controls and procedures are designed to ensure that material information relating to the Company and its subsidiaries is made known to the chief executive officer and chief financial officer of the Company by others within the Company or any of its subsidiaries, and such disclosure controls and procedures are reasonably effective to perform the functions for which they were established subject to the limitations of any such control system; the Company’s auditors and the Audit Committee of the Board of Directors of the Company have been advised of: (i) any significant deficiencies or material weaknesses in the design or operation of internal controls which could adversely affect the Company’s ability to record, process, summarize, and report financial data; and (ii) any fraud, whether or not material, that involves management or other employees who have a role in the Company’s internal controls; and since the date of the most recent evaluation of such disclosure controls and procedures, there have been no significant changes in internal controls or in other factors that could significantly affect internal controls, including any corrective actions with regard to significant deficiencies and material weaknesses.

(gg) The Company and its subsidiaries maintain a system of accounting controls that is in compliance in all material respects with the Sarbanes-Oxley Act and is sufficient to provide reasonable assurances that: (i) transactions are executed in accordance with management’s general or specific authorization; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain

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accountability for assets; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; (iv) the recorded accountability for assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences; and (v) the interactive data in eXtensible Business Reporting Language included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus fairly present the information called for in all material respects and are prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(hh) Each of the Company and its subsidiaries are insured by recognized, financially sound institutions with policies in such amounts and with such deductibles and covering such risks as management of the Company has reasonably determined to be adequate and customary for their businesses. The Company has no reason to believe that it or any of its subsidiaries will not be able (i) to renew its existing insurance coverage as and when such policies expire or (ii) to obtain comparable coverage from similar institutions, in each case, as may be necessary or appropriate to conduct its business as now conducted and at a cost that would not result in a Material Adverse Change. Neither the Company nor any of its subsidiaries has been denied any insurance coverage which it has sought or for which it has applied.

(ii) Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is aware of, or in connection with their services for the Company or any of its subsidiaries, has taken any action, directly or indirectly, that would result in a violation by such persons of the FCPA (as defined below) or any other applicable anti-bribery or anti-corruption laws or regulations, including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA or any other applicable anti-bribery or anti-corruption laws or regulations; and the Company, its subsidiaries and, to the knowledge of the Company, its affiliates have conducted their businesses in compliance with the FCPA and any other applicable anti-bribery or anti-corruption laws or regulations and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

“FCPA” means Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder.

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(jj) The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the United and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001, the money laundering statutes of all applicable jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the best knowledge of the Company, threatened.

(kk) Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is currently subject to any sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department, the U.S. Department of Commerce, the U.S. Department of State or the United Nations Security Council (collectively, “Sanctions”); and the Company will not directly or indirectly use the proceeds of the offering, or lend, contribute or otherwise make available such proceeds to any of its subsidiaries, joint venture partners or other persons, (i) to fund any activities of or business with any person that, at the time of such funding, is the subject of Sanctions, or is in Cuba, Iran, Libya, North Korea, Sudan, Syria or Crimea (each, a “Sanctioned Country”) or in any other country or territory, that, at the time of such funding, is the subject of Sanctions, or (ii) in any other manner that will result in a violation by any person (including any person participating in the offering, whether as underwriter, advisor, investor or otherwise) of Sanctions. For the past five years, the Company and its subsidiaries have not knowingly engaged in, are not now knowingly engaged in and will not engage in any dealings or transactions with any person that at the time of the dealing or transaction is or was the subject or the target of Sanctions or with any Sanctioned Country.

(ll) Neither the Company nor any of its subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against the Company or any of its subsidiaries or any Underwriter for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Shares.

(mm) The Company has not taken nor will take, directly or indirectly, any action designed to or that might be reasonably expected to cause or result in stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Shares.

(nn) Neither the Company nor any of its subsidiaries nor, to their knowledge, any agent thereof acting on their behalf has taken, and none of them will take, any action that might cause this Agreement or the issuance or sale of the Shares to violate Regulation T, Regulation U or Regulation X of the Board of Governors of the Federal Reserve System.

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(oo) No forward-looking statement (within the meaning of Section 27A of the Act and Section 21E of the Exchange Act) contained in the Registration Statement, the Time of Sale Information or the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(pp) The Company and its subsidiaries and their respective officers and directors are in compliance in all material respects with the applicable provisions of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act,” which term, as used herein, includes the rules and regulations of the Commission promulgated thereunder).

7. Expenses. Whether or not the transactions contemplated hereby are consummated or this Agreement becomes effective or is terminated, the Company agrees to pay or cause to be paid the following: (i) the fees, disbursements and expenses of the Company’s counsel and accountants in connection with the registration of the Shares under the Act and all other expenses in connection with the preparation, printing and filing of the Registration Statement and the Prospectus and amendments and supplements thereto and the mailing and delivering of copies thereof and of any Preliminary Prospectus to the Underwriters and dealers; (ii) the printing and delivery (including postage, air freight charges and charges for counting and packaging) of such copies of the Registration Statement, the Prospectus, each Preliminary Prospectus, the Time of Sale Information, the Blue Sky memoranda, this Agreement and all amendments or supplements to any of them as may be reasonably requested for use in connection with the offering and sale of the Shares; (iii) consistent with the provisions of Section 5(j), expenses in connection with the qualification of the Shares for offering and sale under state securities laws or Blue Sky laws, including reasonable and documented attorneys’ fees and out-of-pocket expenses of the counsel for the Underwriters in connection therewith; (iv) the filing fees incident to securing any required review by FINRA of the fairness of the terms of the sale of the Shares and the reasonable and documented fees and disbursements of the Underwriters’ counsel relating thereto, which fees and expenses under this clause (iv) when taken together with all fees and expenses pursuant to clause (iii) above, shall not exceed $10,000; (v) the fees and expenses associated with listing the Shares on the Nasdaq; (vi) the cost of preparing stock certificates representing the Shares, if any; (vii) the costs and charges of any transfer agent or registrar; (viii) the cost of the tax stamps, if any, in connection with the issuance and delivery of the Shares to the respective Underwriters; (ix) all other fees, costs and expenses referred to in Item 14 of the Registration Statement; and (x) the transportation, lodging, graphics and other expenses incidental to the Company’s preparation for and participation in the “roadshow” for the offering contemplated hereby (provided, for the avoidance of doubt, that the transportation and lodging expenses of the representatives of the Underwriters shall be paid by the Underwriters). Except as provided in this Section 7 and in Section 8 hereof, the Underwriters shall pay their own expenses, including the fees and disbursements of their counsel. In addition, in the event that the proposed offering is terminated for the reasons set forth in Section 5(m) hereof, the Company agrees to reimburse the Underwriters as provided in Section 5(m).

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8. Indemnification and Contribution.

(a) Subject to the limitations in this paragraph below, the Company agrees to indemnify and hold harmless you and each other Underwriter, the directors, officers, employees and agents of each Underwriter, and each person, if any, who controls any Underwriter within the meaning of Section 15 of the Act or Section 20 of the Exchange Act from and against any and all losses, claims, damages, liabilities and expenses, including reasonable costs of investigation and attorneys’ fees and expenses (collectively, “Damages”) arising out of or based upon (i) any untrue statement or alleged untrue statement of a material fact contained in any Preliminary Prospectus, in the Registration Statement, the Time of Sale Information, any Issuer Free Writing Prospectus or the Prospectus or in 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 the case of the Prospectus, in light of the circumstances under which they were made) not misleading, except to the extent that any such Damages arise out of or are based upon an untrue statement or omission or alleged untrue statement or omission that has been made therein or omitted therefrom in reliance upon and in conformity with the information furnished in writing to the Company by or on behalf of any Underwriter through you, expressly for use in connection therewith or (ii) any inaccuracy in or breach of the representations and warranties of the Company contained herein or any failure of the Company to perform its obligations hereunder or under law. This indemnification shall be in addition to any liability that the Company may otherwise have.

(b) If any action or claim shall be brought against any Underwriter or any person controlling any Underwriter in respect of which indemnity may be sought against the Company, such Underwriter or such controlling person shall promptly notify in writing the party(s) against whom indemnification is being sought (the “indemnifying party” or “indemnifying parties”), and such indemnifying party(s) shall assume the defense thereof, including the employment of counsel reasonably acceptable to such Underwriter or such controlling person and the payment of all reasonable fees of and expenses incurred by such counsel. Such Underwriter or any such controlling person shall have the right to employ separate counsel in any such action and participate in the defense thereof, but the fees and expenses of such counsel shall be at the expense of such Underwriter or such controlling person, unless (i) the indemnifying party(s) has (have) agreed in writing to pay such fees and expenses, (ii) the indemnifying party(s) has (have) failed to assume the defense and employ counsel reasonably acceptable to the Underwriter or such controlling person or (iii) the named parties to any such action (including any impleaded parties) include both such Underwriter or such controlling person and the indemnifying party(s), and such Underwriter or such controlling person shall have been advised by its counsel that one or more legal defenses may be available to the Underwriter that may not be available to the Company, or that representation of such indemnified party and any indemnifying party(s) by the same counsel would be inappropriate under applicable standards of professional conduct (whether or not such representation by the same counsel has

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been proposed) due to actual or potential differing interests between them (in which case the indemnifying party(s) shall not have the right to assume the defense of such action on behalf of such Underwriter or such controlling person (but the Company shall not be liable for the fees and expenses of more than one counsel for the Underwriters and such controlling persons)). The indemnifying party(s) shall not be liable for any settlement of any such action effected without its (their several) written consent, but if settled with such written consent, or if there be a final judgment for the plaintiff, in any such action, the indemnifying party(s) agree(s) to indemnify and hold harmless any Underwriter and any such controlling person from and against any loss, claim, damage, liability or expense by reason of such settlement or judgment, but in the case of a judgment only to the extent stated in this Section 8(b).

(c) Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers who sign the Registration Statement and any person who controls the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, to the same extent as the foregoing several indemnity from the Company to each Underwriter, but only with respect to information furnished in writing by or on behalf of such Underwriter through you expressly for use in the Registration Statement, the Prospectus, the Time of Sale Information, any Issuer Free Writing Prospectus or any Preliminary Prospectus, or any amendment or supplement thereto. If any action or claim shall be brought or asserted against the Company, any of its directors, any of its officers or any such controlling person based on the Registration Statement, the Prospectus, the Time of Sale Information or any Preliminary Prospectus, or any amendment or supplement thereto, and in respect of which indemnity may be sought against any Underwriter pursuant to this paragraph, such Underwriter shall have the rights and duties given to the Company by Section 8(b) (except that if the Company shall have assumed the defense thereof such Underwriter shall not be required to do so, but may employ separate counsel therein and participate in the defense thereof, but the fees and expenses of such counsel shall be at such Underwriter’s expense), and the Company, its directors, any such officers and any such controlling persons, shall have the rights and duties given to the Underwriters by the immediately preceding paragraph.

(d) In any event, the Company will not, without the prior written consent of the Representative, settle or compromise or consent to the entry of any judgment in any proceeding or threatened claim, action, suit or proceeding in respect of which the indemnification may be sought hereunder (whether or not the Representative or any person who controls the Representative within the meaning of Section 15 of the Act or Section 20 of the Exchange Act is a party to such claim, action, suit or proceeding) unless such settlement, compromise or consent includes an unconditional release of all Underwriters and such controlling persons from all liability arising out of such claim, action, suit or proceeding.

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(e) If the indemnification provided for in this Section 8 is unavailable or insufficient for any reason whatsoever to an indemnified party in respect of any Damages referred to herein, then an 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 Damages (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand, and the Underwriters on the other hand, from the offering and sale of the Shares or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative and several fault of the Company on the one hand, and the Underwriters on the other hand, in connection with the statements or omissions that resulted in such Damages as well as any other relevant equitable considerations. The relative and several benefits received by the Company on the one hand, and the Underwriters on the other hand, shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company bear to the total underwriting discounts and commissions received by the Underwriters, in each case as set forth in the table on the cover page of the Prospectus; provided that, in the event that the Underwriters shall have purchased any Additional Shares hereunder, any determination of the relative benefits received by the Company or the Underwriters from the offering of the Shares shall also include the net proceeds (before deducting expenses) received by the Company and the underwriting discounts and commissions received by the Underwriters, from the sale of such Additional Shares. The relative fault of the Company on the one hand, and the Underwriters 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 Company on the one hand, or by the Underwriters on the other hand and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 8 was determined by a pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take into account the equitable considerations referred to in the immediately preceding paragraph. The amount paid or payable by an indemnified party as a result of the Damages 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 Section 8, no Underwriter shall be required to contribute any amount in excess of the amount of the underwriting discounts and commissions received by such Underwriter in connection with the Shares underwritten by it and distributed to the public. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to this Section 8 are several in proportion to the respective numbers of Firm Shares set forth opposite their names in Schedule I hereto (or such numbers of Firm Shares increased as set forth in Section 11 hereof) and not joint.

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(f) Any Damages for which an indemnified party is entitled to indemnification or contribution under this Section 8 shall be paid by the indemnifying party to the indemnified party as Damages are incurred after receipt of reasonably itemized invoices therefor. The indemnity, contribution and reimbursement agreements contained in this Section 8 and the representations and warranties of the Company set forth in this Agreement shall remain operative and in full force and effect, regardless of (i) any investigation made by or on behalf of any Underwriter or any person controlling any Underwriter, the Company, its directors or officers or any person controlling the Company, (ii) acceptance of any Shares and payment therefor hereunder and (iii) any termination of this Agreement. A successor to any Underwriter or any person controlling any Underwriter, or to the Company, its directors or officers or any person controlling the Company, shall be entitled to the benefits of the indemnity, contribution and reimbursement agreements contained in this Section 8.

9. Conditions of Underwriters’ Obligations. The several obligations of the Underwriters to purchase the Firm Shares and the Additional Shares, as the case may be, hereunder are subject to the following conditions:

(a) The Registration Statement shall have become effective not later than 12:00 noon, New York City time, on the date hereof, or at such later date and time as shall be consented to in writing by the Representative, and all filings required by Rules 424(b) and 430B under the Act shall have been timely made.

(b) Subsequent to the respective dates as of which information is given in the Registration Statement, the Time of Sale Information and Prospectus, (i) there shall not have been any material change in the capital stock of the Company or any material change in the indebtedness (other than in the ordinary course of business) of the Company, (ii) except as set forth or contemplated by the Registration Statement, the Time of Sale Information or the Prospectus, or the documents incorporated by reference therein, no material oral or written agreement or other transaction shall have been entered into by the Company that is not in the ordinary course of business or that could reasonably be expected to result in a material reduction in the future earnings of the Company, (iii) no loss or damage (whether or not insured) to the property of the Company shall have been sustained that had or could reasonably be expected to result in a Material Adverse Change, (iv) no legal or governmental action, suit or proceeding affecting the Company or any of its properties that is material to the Company or that affects or could reasonably be expected to affect the transactions contemplated by this Agreement shall have been instituted or threatened and (v) there shall not have been any material change in the condition (financial or otherwise), business, management or results of operations of the Company or its subsidiaries, considered as one entity, that makes it impractical or inadvisable in your judgment to proceed with the offering or purchase of the Shares as contemplated hereby.

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(c) You shall have received on the Closing Date (i) an opinion of Wilmer Cutler Pickering Hale and Dorr LLP, counsel to the Company, substantially in the form attached hereto as Annex A-1 and (ii) an opinion of David Schmitt, General Counsel of the Company, substantially in the form attached hereto as Annex A-2.

(d) You shall have received on the Closing Date a written certificate executed by the officer of the Company responsible for environmental compliance, substantially in the form attached hereto as Annex B.

(e) You shall have received on the Closing Date an opinion of Proskauer Rose LLP, as counsel for the Underwriters, dated the Closing Date, with respect to the issuance and sale of the Shares, the Registration Statement and other related matters as you may reasonably request, and the Company and its counsel shall have furnished to Proskauer Rose LLP such documents as they may reasonably request for the purpose of enabling them to pass upon such matters.

(f) You shall have received letters addressed to you and dated the date hereof and the Closing Date, as the case may be, from the firm of RSM US LLP, independent certified public accountants, substantially in the form heretofore approved by you.

(g) You shall have received a written certificate of the chief financial officer of the Company, dated the date hereof and the Closing Date, as the case may be, in form and substance previously agreed by the Company and you.

(h) (i) No stop order suspending the effectiveness of the Registration Statement shall have been issued by the Commission and no proceedings for that purpose shall be pending or, to the knowledge of the Company, shall be threatened or contemplated by the Commission at or prior to the Closing Date, as the case may be; (ii) no order suspending the effectiveness of the Registration Statement or the qualification or registration of the Shares under the securities or Blue Sky laws of any jurisdiction shall be in effect and no proceeding for such purpose shall be pending or, to the knowledge of the Company, threatened or contemplated by the authorities of any jurisdiction; (iii) any request for additional information on the part of the staff of the Commission or any such authorities shall have been complied with to the satisfaction of the staff of the Commission or such authorities; (iv) after the date hereof, no amendment or supplement to the Registration Statement or the Prospectus shall have been filed unless a copy thereof was first submitted to you and you did not object thereto in good faith; and (v) all of the representations and warranties of the Company contained in this Agreement shall be true and correct in all material respects (except for such representations and warranties qualified by materiality, which representations and warranties shall be true and correct in all respects) on and as of the date hereof and on and as of the Closing Date as if made on and as of the Closing Date, and you shall have received a certificate, dated the Closing Date and signed by the chief executive officer and the chief financial officer of the Company (or such other officers as are acceptable to you) to the effect set forth in this Section 9(h) and in Section 9(b).

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(i) The Company shall not have failed in any material respect at or prior to the Closing Date to have performed or complied with any of its agreements herein contained and required to be performed or complied with by it hereunder at or prior to the Closing Date.

(j) The Company shall have furnished or caused to have been furnished to you such further certificates and documents as you shall have reasonably requested.

(k) At or prior to the Closing Date, you shall have received the written Lock-Up Agreements substantially in the form attached as Exhibit A from each of the Company’s executive officers and directors listed in Schedule VI.

All such opinions, certificates, letters and other documents will be in compliance with the provisions hereof only if they are reasonably satisfactory in form and substance to you and your counsel.

The several obligations of the Underwriters to purchase Additional Shares hereunder are subject to the satisfaction on and as of the Additional Closing Date of the conditions set forth in this Section 9, except that, if the Additional Closing Date is other than the Closing Date, the certificates, opinions and letters referred to in this Section 9 shall be dated as of the Additional Closing Date and the opinions called for by paragraphs (c) and (e) shall be revised to reflect the sale of Additional Shares.

If any of the conditions hereinabove provided for in this Section 9 shall not have been satisfied when and as required by this Agreement, this Agreement may be terminated by you by notifying the Company of such termination in writing or by telegram at or prior to such Closing Date, but you shall be entitled to waive any of such conditions.

10. Effective Date of Agreement. This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

11. Defaulting Underwriters. If any one or more of the Underwriters shall fail or refuse to purchase Firm Shares that it or they have agreed to purchase hereunder, and the aggregate number of Firm Shares that such defaulting Underwriter or Underwriters agreed but failed or refused to purchase is not more than one-tenth of the aggregate number of the Firm Shares, each non-defaulting Underwriter shall be obligated, severally, in the proportion in which the number of Firm Shares set forth opposite its name in Schedule I hereto bears to the aggregate number of Firm Shares set forth opposite the names of all non-defaulting Underwriters or in such

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other proportion as you may specify in the Agreement Among Underwriters, to purchase the Firm Shares that such defaulting Underwriter or Underwriters agreed, but failed or refused to purchase. If any Underwriter or Underwriters shall fail or refuse to purchase Firm Shares and the aggregate number of Firm Shares with respect to which such default occurs is more than one-tenth of the aggregate number of Firm Shares and arrangements satisfactory to you and the Company for the purchase of such Firm Shares are not made within 48 hours after such default, this Agreement will terminate without liability on the part of any non-defaulting Underwriter or the Company. In any such case that does not result in termination of this Agreement, either you or the Company shall have the right to postpone the Closing Date, but in no event for longer than seven (7) days, in order that the required changes, if any, in the Registration Statement and the Prospectus or any other documents or arrangements may be effected. Any action taken under this paragraph shall not relieve any defaulting Underwriter from liability in respect of any such default of any such Underwriter under this Agreement.

12. Termination of Agreement. This Agreement shall be subject to termination in your absolute discretion, without liability on the part of any Underwriter to the Company by notice to the Company, if prior to the Closing Date or the Additional Closing Date (if different from the Closing Date and then only as to the Additional Shares), as the case may be, in your sole judgment, (i) trading in the Company’s Class A Common Stock shall have been suspended by the Commission or the Nasdaq, (ii) trading in securities generally on the NYSE or Nasdaq shall have been suspended or materially limited, or minimum or maximum prices shall have been generally established on such exchange, or additional material governmental restrictions, not in force on the date of this Agreement, shall have been imposed upon trading in securities generally by any such exchange or by order of the Commission or any court or other governmental authority, (iii) a general moratorium on commercial banking activities shall have been declared by either federal or New York State authorities, (iv) any downgrading shall have occurred in the rating accorded the Company’s debt securities by any “nationally recognized statistical rating organization”, as that term is defined in Section 3(a)(62) of the Exchange Act, (v) any such organization shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of any of the Company’s debt securities or (vi) there shall have occurred any outbreak or escalation of hostilities or other international or domestic calamity, crisis or change in political, financial or economic conditions or other material event the effect of which on the financial markets of the United States is such as to make it, in your judgment, impracticable or inadvisable to market the Shares or to enforce contracts for the sale of the Shares. Notice of such termination shall be promptly given to the Company and its counsel by telegraph, telecopy or telephone and shall be subsequently confirmed by letter.

13. Information Furnished by the Underwriters. The Company acknowledges that, in any Preliminary Prospectus, Time of Sale Information or Prospectus (i) the names of the Underwriters appearing on the front and back cover pages, (ii) the names of the Underwriters appearing in the table in the first paragraph under the caption “Underwriting,” and (iii) the

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language in the sections captioned “Commissions and Discounts,” “Price Stabilization, Short Positions and Penalty Bids” and “Electronic Distribution” under the caption “Underwriting”, constitute the only information furnished by or on behalf of the Underwriters through you or on your behalf as such information is referred to in Sections 6(d), 6(f), 6(g) and 8 hereof.

14. Miscellaneous. Except as otherwise provided in Sections 5 and 12 hereof, notice given pursuant to any of the provisions of this Agreement shall be in writing and shall be delivered:

Casella Waste Systems, Inc.

25 Greens Hill Lane

Rutland, Vermont 05701

Attention: John W. Casella

with a copy to:

Wilmer Cutler Pickering Hale and Dorr LLP

60 State Street

Boston, Massachusetts 02109

Attention: Jeffrey A. Stein

Raymond James & Associates, Inc.

880 Carillon Parkway

St. Petersburg, Florida 33716

Attention: John Critchlow

with a copy to

Proskauer Rose LLP

Eleven Times Square

New York, New York 10036

Attention: Frank J. Lopez

This Agreement has been and is made solely for the benefit of the several Underwriters, the Company and its directors and officers.

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15. Applicable Law; Counterparts. This Agreement shall be governed by and construed in accordance with the laws of the State of New York.

This Agreement may be signed in various counterparts, which together shall constitute one and the same instrument.

This Agreement shall be effective when, but only when, at least one counterpart hereof shall have been executed on behalf of each party hereto.

The Company and the Underwriters each hereby irrevocably waive any right they may have to a trial by jury in respect to any claim based upon or arising out of this Agreement or the transactions contemplated hereby.

16. Amendment; Waiver. No amendment or wavier of any provision of this 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 hereto.

17. No Fiduciary Duty. Notwithstanding any pre-existing relationship, advisory or otherwise, between the parties or any oral representations or assurances previously or subsequently made by any of the Underwriters, the Company acknowledges and agrees that (i) nothing herein shall create a fiduciary or agency relationship between the Company, on the one hand, and the Underwriters, on the other hand; (ii) the Underwriters have been retained solely to act as underwriters and are not acting as advisors, expert or otherwise, to either the Company in connection with this offering, the sale of the Shares or any other services the Underwriters may be deemed to be providing hereunder, including, without limitation, with respect to the public offering price of the Shares; (iii) the relationship between the Company, on the one hand, and the Underwriters, on the other hand, is entirely and solely commercial, and the price of the Shares was established by the Company and the Underwriters based on discussions and arms’ length negotiations and the Company understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement; (iv) any duties and obligations that the Underwriters may have to the Company shall be limited to those duties and obligations specifically stated herein; and (v) notwithstanding anything in this Agreement to the contrary, the Company acknowledges that the Underwriters may have financial interests in the success of the offering that are not limited to the difference between the price to the public and the purchase price paid to the Company for the Shares and such interests may differ from the interests of the Company, and the Underwriters have no obligation to disclose, or account to the Company for any benefit they may derive from such additional financial interests. The Company hereby waives and releases, to the fullest extent permitted by the applicable law, any claims it may have against the Underwriters with respect to any breach or alleged breach of fiduciary duty and agrees that the Underwriters shall have no liability (whether direct or indirect) to the Company in respect of such a fiduciary duty claim or to any person asserting a fiduciary duty claim on behalf of or in right of the Company or any of its shareholders, managers, employees or creditors.

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18. Research Analyst Independence. The Company acknowledges that (a) the Underwriters’ research analysts and research departments are required to be independent from their respective investment banking divisions and are subject to certain regulations and internal policies and (b) the Underwriters’ research analysts may hold views and make statements or investment recommendations and/or publish research reports with respect to the Company, the value of the Class A Common Stock and/or the offering that differ from the views of their respective investment banking divisions. The Company hereby waives and releases, to the fullest extent permitted by law, any claims that it may have against the Underwriters with respect to any conflict of interest that may arise from the fact that the views expressed by the Underwriters’ independent research analysts and research departments may be different from or inconsistent with the views or advice communicated to the Company by any Underwriter’s investment banking division. The Company acknowledges that each of the Underwriters is a full service securities firm and as such, from time to time, subject to applicable securities laws, may effect transactions for its own account or the account of its customers and hold long or short positions in debt or equity securities of the companies that are the subject of the transactions contemplated by this Agreement.    

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Please confirm that the foregoing correctly sets forth the agreement among the Company and the Underwriters.

[Signature Page to Underwriting Agreement]

SCHEDULE I

SCHEDULE II

Issuer Free Writing Prospectus

None.

SCHEDULE III

Subsidiaries

Casella Major Account Services, LLC

Casella Waste Management, Inc.

Casella Transportation, Inc.

Northern Properties Corporation of Plattsburgh

Casella Waste Management of Pennsylvania, Inc.

CV Landfill, Inc.

Hiram Hollow Regeneration Corp.

All Cycle Waste, Inc.

Casella Waste Management of Massachusetts, Inc.

Oxford Transfer Station LLC

Casella of Holyoke, Inc.

Casella Waste Management of N.Y., Inc.

Portland C & D Site, Inc.

Schultz Landfill, Inc.

Waste-Stream, Inc.

Blow Bros.

NEWS of Worcester LLC

New England Waste Services, Inc.

New England Waste Services of Vermont, Inc.

North Country Environmental Services, Inc.

Bristol Waste Management, Inc.

Newbury Waste Management, Inc.

Sunderland Waste Management, Inc.

Forest Acquisitions, Inc.

Hardwick Landfill, Inc.

Southbridge Recycling and Disposal Park, Inc.

New England Waste Services of N.Y., Inc.

The Hyland Facility Associates

Hakes C & D Disposal, Inc.

Chemung Landfill LLC

GroundCo LLC

Casella Waste Services of Ontario LLC

Tompkins County Recycling LLC

KTI, Inc.

Casella Recycling LLC

KTI Environmental Group, Inc.

Pine Tree Waste, Inc.

KTI Specialty Waste Services, Inc.

New England Waste Services of ME, Inc.

NEWSME Landfill Operations LLC

RecycleBank LLC

SCHEDULE IV

Direct and Indirect Equity or Ownership Interest of the Company

Agreen Energy LLC

Asian Energy Limited, Inc.

Bgreen Energy LLC

Evergreen National Indemnity Company

GreenerU, Inc.

RecycleRewards, Inc.

SCHEDULE V

Pricing Terms

1. The Company is selling 3,100,000 Firm Shares.

2. The Company has granted an option to the Underwriters to purchase up to an additional 465,000 Additional Shares.

3. The public offering price per share for the Shares conveyed to the investors at the time of confirmation.

SCHEDULE VI

Persons Subject to Lock-up

EXHIBIT A

Form of Lock-up Agreement

Form of Lock-up Agreement

[    ], 2019

CASELLA WASTE SYSTEMS, INC.

25 Green Hill Lane

Rutland, VT 05701

RAYMOND JAMES & ASSOCIATES, INC.

As Representative of the Several Underwriters

c/o Raymond James & Associates, Inc

880 Carillon Parkway

St. Petersburg, FL 33716

Ladies and Gentlemen:

This letter agreement is delivered to you pursuant to the Underwriting Agreement (the “Underwriting Agreement”) to be entered into by the Company, as issuer, and Raymond James & Associates, Inc., the representative (the “Representative”) of the underwriters (the “Underwriters”) to be named therein. Upon the terms and subject to the conditions of the Underwriting Agreement, the Underwriters intend to effect a public offering of Class A Common Stock, par value $0.01 per share (the “Class A Common Stock”), of the Company (the “Shares”), as described in and contemplated by the registration statement of the Company on Form S-3, File No. 333-224788 (the “Registration Statement”), as filed with the Securities and Exchange Commission (the “Offering”). Terms used herein, but not defined, shall have the meaning ascribed to them in the Underwriting Agreement.

The undersigned recognizes that it is in the best financial interests of the undersigned, as an officer or director, or an owner of Class A Common Stock, Class B Common Stock, options or other equity securities of the Company (the “Company Securities”), that the Company complete the proposed Offering.

The undersigned further recognizes that the Company Securities held by the undersigned are, or may be, subject to certain restrictions on transferability, including those imposed by United States federal securities laws. Notwithstanding these restrictions, the undersigned has agreed to enter into this letter agreement to further assure the Underwriters that the Company Securities of the undersigned, now held or hereafter acquired, will not enter the public market at a time that might impair the underwriting effort.

Therefore, as an inducement to the Underwriters to execute the Underwriting Agreement, the undersigned hereby acknowledges and agrees that, without the prior written consent of the Representative on behalf of the Underwriters, the undersigned will not (i) offer, sell, contract to sell, pledge, grant any option to purchase or otherwise dispose of (collectively, a “Disposition”) any Company Securities, or any securities convertible into or exercisable or exchangeable for, or any rights to purchase or otherwise acquire, any Company Securities held by the undersigned or acquired by the undersigned after the date hereof, or that may be deemed to be beneficially owned by the undersigned (collectively, the “Lock-Up Shares”), pursuant to the Rules and Regulations promulgated under the Securities Act of 1933, as amended (the “Act”), and the Securities Exchange Act of 1934, as amended (the “Exchange Act”), for a period commencing on the date hereof and ending on the day that is 30 days after the date of the Company’s Prospectus first filed pursuant to Rule 424(b) under the Act (the “Lock-Up Period”) or publicly disclose the intention to make any offer, sale pledge or disposition, (ii) exercise or seek to exercise or effectuate in any manner any rights of any nature that the undersigned has or may have hereafter to require the Company to register under the Act the undersigned’s sale, transfer or other disposition of any of the Lock-Up Shares during the Lock-up Period (iii) otherwise participate as a selling securityholder in any manner in any registration of Lock-Up Shares effected by the Company under the Act, including under the Registration Statement, during the Lock-Up Period, or (iv) engage in any hedging, collar (whether or not for any consideration) or other transaction that is designed to or reasonably expected to lead or result in a Disposition of Lock-Up Shares during the Lock-Up Period, even if such Lock-Up Shares would be disposed of by someone other than such holder. Such prohibited hedging or other transactions would include any short sale or any purchase, sale or grant of any right (including any put or call option or reversal or cancellation thereof) with respect to any Lock-Up Shares or with respect to any security (other than a broad-based market basket or index) that includes, relates to or derives any significant part of its value from Lock-Up Shares.

Notwithstanding the agreement not to make any Disposition during the Lock-Up Period, you have agreed that the foregoing restrictions shall not apply to:

provided, further, that in the case of any transfer or distribution pursuant to clause (1), (4), (5), (6), (7) or (10) each donee, transferee or distributee shall execute and deliver to the Representative a letter agreement in the form of this paragraph; and provided, further, that in the case of any transfer or distribution pursuant to clause (1), (3), (4), (6) or (7) no filing by any party (donor, donee, transferor or transferee) under the Exchange Act or other public announcement shall be required or shall be made voluntarily in connection with such transfer or distribution (other than a filing on a Form 5 made after the expiration of the Lock-Up Period).

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this letter agreement. All authority herein conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs or personal representatives of the undersigned.

It is understood that, if the Underwriting Agreement (other than the provisions thereof that survive termination) shall terminate or be terminated prior to payment for and delivery of the Shares, the undersigned shall be released from the obligations under this letter agreement. Notwithstanding the foregoing, the undersigned shall be released from all obligations under this letter agreement if the Offering has not been commenced by February 28, 2019 or has otherwise been terminated by the Company and the Underwriters.

In furtherance of the foregoing, the Company and its transfer agent and registrar are hereby authorized to decline to make any transfer of Lock-Up Shares if such transfer would constitute a violation or breach of this letter agreement. This letter agreement shall be binding on the undersigned and the respective successors, heirs, personal representatives and assigns of the undersigned.

ANNEX A-1

Form of Opinion of Wilmer Cutler Pickering Hale and Dorr LLP

ANNEX A-2

Form of Opinion of General Counsel of the Company

ANNEX B

Environmental Compliance Certificate

EXECUTION VERSION

CASELLA WASTE SYSTEMS, INC.

FIRST AMENDMENT TO UNDERWRITING AGREEMENT

January 23, 2019

Raymond James & Associates, Inc.

As Representative of the Underwriters

Raymond James & Associates, Inc.

880 Carillon Parkway

St. Petersburg, FL 33716

Ladies and Gentlemen:

This First Amendment to Underwriting Agreement (this “Amendment”) is made and is effective as of January 23, 2019, by and between Casella Waste Systems, a corporation organized under the laws of Delaware (the “Company”), and Raymond James & Associates, Inc., as representative (the “Representative”) of the several underwriters named in Schedule I of the Underwriting Agreement (defined below). The Company and Representative are referred to herein as the “Parties.”

RECITALS

WHEREAS, the Parties entered into a certain Underwriting Agreement dated as of January 22, 2019 (the “Underwriting Agreement”); and

WHEREAS, the Parties desire to amend the Underwriting Agreement in certain respects;

NOW, THEREFORE, for good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Parties hereby agree as follows:

Upon the basis of the representations, warranties and agreements of the Company herein contained and subject to all the terms and conditions set forth herein, each Underwriter agrees, severally and not jointly, to purchase from the Company at a purchase price of $28.315 per Share (the “purchase price per Share”), the number of Firm Shares set forth opposite the name of such Underwriter in Schedule I hereto.

2. Schedule I of the Underwriting Agreement is hereby amended to replace the Schedule I therein in its entirety with the Schedule I attached hereto.

3. Except as expressly amended by the terms of this Amendment, the Underwriting Agreement shall remain in full force and effect in accordance with its terms.

4. All capitalized terms used in this Amendment and not otherwise defined shall have the definitions ascribed to such terms in the Underwriting Agreement.

5. References in the Underwriting Agreement to the “Agreement” shall mean the Underwriting Agreement, as amended by this Amendment.

6. This Amendment shall be governed by and construed in accordance with the laws of the State of New York.

7. The Company and the Underwriters each hereby irrevocably waive any right they may have to a trial by jury in respect to any claim based upon or arising out of this Amendment or the transactions contemplated hereby.

8. This Amendment may be signed in various counterparts, which together shall constitute one and the same instrument. This Amendment shall be effective when, but only when, at least one counterpart hereof shall have been executed on behalf of each party hereto.

[Signature Pages Follow]

2

If the foregoing is in accordance with your understanding of our agreement, please sign and return to us the enclosed duplicate hereof, whereupon this letter and your acceptance shall represent a binding agreement among the Company and the several Underwriters.

[Signature Page to First Amendment to Underwriting Agreement]

The foregoing Amendment is hereby

confirmed and accepted as of the date first

above written.

[Signature Page to First Amendment to Underwriting Agreement]

SCHEDULE I