Exhibit 1.1

ESCO Corporation

Class A Common Stock, no par value per share

Underwriting Agreement

[·], 2012

Goldman, Sachs & Co.

Morgan Stanley & Co. LLC

As representatives of the several Underwriters

named in Schedule I hereto,

c/o Goldman, Sachs & Co.

200 West Street

New York, New York 10282-2198

c/o Morgan Stanley & Co. LLC

1585 Broadway

New York, New York 10036-8293

Ladies and Gentlemen:

ESCO Corporation, an Oregon corporation (the “Company”), proposes, subject to the terms and conditions stated herein, to issue and sell to the Underwriters named in Schedule I hereto (the “Underwriters”), for whom Goldman, Sachs & Co. and Morgan Stanley & Co. LLC are acting as representatives (the “Representatives”), an aggregate of [·] shares and, at the election of the Underwriters, up to [·] additional shares of Class A Common Stock, (“Stock”) of the Company and the stockholders of the Company named in Schedule III hereto (the “Selling Stockholders”) propose, subject to the terms and conditions stated herein, to sell to the Underwriters an aggregate of [·] shares of Stock. The aggregate of [·] shares to be sold by the Company and the Selling Stockholders is herein called the “Firm Shares” and the aggregate of [·] additional shares to be sold by the Company is herein called the “Optional Shares”. The Firm Shares and the Optional Shares that the Underwriters elect to purchase pursuant to Section 3 hereof are herein collectively called the “Shares”.

1. The Company represents and warrants to, and agrees with, each of the Underwriters that:

(a) A registration statement on Form S-1 (File No. 333-173841) (the “Initial Registration Statement”) in respect of the Shares has been filed with the Securities and Exchange Commission (the “Commission”); the Initial Registration Statement and any post-effective amendment thereto, each in the form heretofore delivered to you, and, excluding exhibits thereto, to you for each of the other Underwriters, have been declared effective by the Commission in such form; other than a registration statement, if any, increasing the size of the offering (a “Rule 462(b) Registration Statement”), filed pursuant to Rule 462(b) under the Securities Act of 1933, as amended (the “Act”), which became effective upon filing, no other document with respect to the Initial Registration Statement has heretofore been filed with the Commission; and no stop order suspending the effectiveness of the Initial Registration Statement, any post-effective amendment thereto or the Rule 462(b) Registration Statement, if any, has been issued and no proceeding for that purpose has been initiated or threatened by the Commission (any preliminary prospectus included in the Initial Registration Statement or filed with the Commission pursuant to Rule 424(a) of the rules and regulations of the Commission under the Act is hereinafter called a “Preliminary Prospectus”); the various parts of the Initial Registration Statement and the Rule 462(b) Registration Statement, if any, including all exhibits thereto and including the information contained in the form of final prospectus filed with the Commission pursuant to Rule 424(b) under the Act in accordance with Section 6(a) hereof and deemed by virtue of Rule 430A under the Act to be part of the Initial Registration Statement at the time it was declared effective, each as amended at the time such part of the Initial Registration Statement became effective or such part of the Rule 462(b) Registration Statement, if any, became or hereafter becomes effective, are hereinafter collectively called the “Registration Statement”; the Preliminary Prospectus relating to the Shares that was included in the Registration Statement immediately prior to the Applicable Time (as defined in Section 1(c) hereof) is hereinafter called the “Pricing Prospectus”; and such final prospectus, in the form first filed pursuant to Rule 424(b) under the Act, is hereinafter called the “Prospectus”; and any “issuer free writing prospectus” as defined in Rule 433 under the Act relating to the Shares is hereinafter called an “Issuer Free Writing Prospectus”);

(b) No order preventing or suspending the use of any Preliminary Prospectus or any Issuer Free Writing Prospectus has been issued by the Commission, and each Preliminary Prospectus, at the time of filing thereof, conformed in all material respects to the requirements of the Act and the rules and regulations of the Commission thereunder, and 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; provided, however,

that this representation and warranty shall not apply to any statements or omissions made in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through the Representatives expressly for use therein;

(c) For the purposes of this Agreement, the “Applicable Time” is [·] (Eastern time) on the date of this Agreement; the Pricing Prospectus, as supplemented by those Issuer Free Writing Prospectuses and other documents listed in Schedule II(b) hereto, taken together (collectively, the “Pricing Disclosure Package”) as of the Applicable Time, did not include any 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; and each Issuer Free Writing Prospectus listed on Schedule II(a) or Schedule II(b) hereto does not conflict with the information contained in the Registration Statement, the Pricing Prospectus or the Prospectus and each such Issuer Free Writing Prospectus, as supplemented by and taken together with the Pricing Disclosure Package as of the Applicable Time, did not include any 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; provided, however, that this representation and warranty shall not apply to statements or omissions made in the Pricing Disclosure Package or an Issuer Free Writing Prospectus in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through the Representatives expressly for use therein;

(d) The Registration Statement conforms, and the Prospectus and any further amendments or supplements to the Registration Statement or the Prospectus will conform, in all material respects to the requirements of the Act and the rules and regulations of the Commission thereunder and do not and will not, as of the applicable effective date as to each part of the Registration Statement and as of the applicable filing date as to the Prospectus and any amendment or supplement thereto, 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, however, that this representation and warranty shall not apply to any statements or omissions made in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through the Representatives expressly for use therein;

(e) Neither the Company nor any of its subsidiaries has sustained since the date of the latest audited financial statements included in the Pricing Prospectus any material loss or material interference with the business of the Company and its subsidiaries (taken as a whole) from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth or contemplated in the Pricing Prospectus; and, since the respective dates as of

which information is given in the Registration Statement and the Pricing Prospectus, there has not been any change in the capital stock (other than issuances of stock pursuant to the exercise of options or Stock Appreciation Rights disclosed in the Pricing Prospectus or the repurchase of stock pursuant to the exercise of put rights described in the Pricing Prospectus) or long-term debt (other than additional amounts borrowed or repaid pursuant to revolving credit arrangements described in the Pricing Prospectus) of the Company or any of its subsidiaries or any material adverse change, or any development involving a prospective material adverse change, in or affecting the general affairs, management, financial position, stockholders’ equity or results of operations of the Company and its subsidiaries taken as a whole (a “Material Adverse Effect”), otherwise than as set forth or contemplated in the Pricing Prospectus;

(f) The Company and its subsidiaries have good and marketable title in fee simple to all real property and good and marketable title to all personal property owned by them, in each case free and clear of all liens, encumbrances and defects except such as are described in the Pricing Prospectus or such as do not materially affect the value of such property and do not materially interfere with the use made and proposed to be made of such property by the Company and its subsidiaries; and any real property and buildings held under lease by the Company and its subsidiaries are held by them under valid, subsisting and enforceable leases with such exceptions as are not material and do not materially interfere with the use made and proposed to be made of such property and buildings by the Company and its subsidiaries;

(g) The Company has been duly incorporated and is validly existing as a corporation under the laws of the State of Oregon, with power and authority (corporate and other) to own its properties and conduct its business as described in the Pricing Prospectus, and has been duly qualified as a foreign corporation for the transaction of business and is in good standing under the laws of each other jurisdiction in which it owns or leases properties or conducts any business so as to require such qualification, or is subject to no material liability or disability by reason of the failure to be so qualified in any such jurisdiction; and each subsidiary of the Company has been duly incorporated and is validly existing as a corporation in good standing under the laws of its jurisdiction of incorporation;

(h) (i) The Company has authorized capital stock as set forth in the Pricing Prospectus and all of the outstanding shares of capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable and conform to the description of the capital stock contained in the Pricing Disclosure Package and Prospectus; (ii) all of the outstanding shares of capital stock of each subsidiary of the Company have been duly authorized and validly issued, are fully paid and non-assessable and (except for directors’ qualifying shares and except as otherwise set forth in the Pricing Prospectus) are owned directly or indirectly by the Company, free and clear of all liens, encumbrances, equities or claims; and (iii) each “significant subsidiary” (as that

term is defined in Rule 1-02(w) of Regulation S-X under the Exchange Act) of the Company is identified on Schedule IV hereof (“Significant Subsidiary”);

(i) The Shares have been duly authorized and, when issued and delivered against payment therefor as provided herein, will be validly issued and fully paid and non-assessable and will conform to the description of the Stock contained in the Prospectus;

(j) The issue and sale of the Shares and the compliance by the Company with this Agreement and the consummation of the transactions herein contemplated will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, nor will such action result in any violation of the provisions of the Articles of Incorporation or By-laws of the Company or any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties; and no consent, approval, authorization, order, registration or qualification of or with any such court or governmental agency or body is required for the issue and sale of the Shares or the consummation by the Company of the transactions contemplated by this Agreement, except the registration under the Act of the Shares and such consents, approvals, authorizations, orders, registrations or qualifications as may be required under state securities or Blue Sky laws or similar laws in jurisdictions outside the United States in connection with the purchase and distribution of the Shares by the Underwriters;

(k) Neither the Company nor any of its subsidiaries is in violation of its Articles of Incorporation, By-laws or similar organizational documents or in default in the performance or observance of any material obligation, agreement, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which it is a party or by which it or any of its properties may be bound;

(l) The statements set forth in the Pricing Prospectus and Prospectus under the caption “Description of Capital Stock”, under the caption “Material United States Federal Income Tax Consequences to Non-U.S. Holders”, and under the caption “Underwriting”, insofar as they purport to describe the provisions of the laws and documents referred to therein, are accurate in all material respects;

(m) Other than as set forth in the Pricing Prospectus, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property of the Company or any of its subsidiaries is the subject which, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse

Effect; and, to the best of the Company’s knowledge, no such proceedings are threatened or contemplated by governmental authorities or others;

(n) The Company is not and, after giving effect to the offering and sale of the Shares and the application of the proceeds thereof, will not be an “investment company”, as such term is defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”);

(o) At the time of filing the Initial Registration Statement the Company was not and is not an “ineligible issuer,” as defined under Rule 405 under the Act;

(p) PricewaterhouseCoopers LLP, who has certified certain financial statements of the Company and its subsidiaries, is an independent registered public accounting firm with respect to the Company as required by the Act and the applicable rules and regulations thereunder adopted by the Commission and the Public Company Accounting Oversight Board (United States)(PCAOB);

(q) The Company maintains a system of internal control over financial reporting (as such term is defined in Rule 13a-15(f) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”)) that complies with the requirements of the Exchange Act and has been designed by the Company’s principal executive officer and principal financial officer, or under their supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. The Company’s internal control over financial reporting is effective and the Company is not aware of any material weaknesses in its internal control over financial reporting;

(r) Since the date of the latest audited financial statements included in the Pricing Prospectus, there has been no change in the Company’s internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting;

(s) The Company maintains disclosure controls and procedures (as such term is defined in Rule 13a-15(e) under the Exchange Act) that comply with the requirements of the Exchange Act; such disclosure controls and procedures have been designed to ensure that material information relating to the Company and its subsidiaries is made known to the Company’s principal executive officer and principal financial officer by others within those entities; and such disclosure controls and procedures are effective;

(t) The Company and its subsidiaries (i) are in compliance with any and all applicable foreign, federal, state, provincial and local laws and regulations relating to the protection of human health and safety, the environment or hazardous or toxic substances, wastes or materials, pollutants or contaminants (“Environmental Laws”), (ii) have received all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses and (iii) are in compliance with all terms and conditions of

any such permit, license or approval, except where such non-compliance with Environmental Laws, failure to receive required permits, licenses or other approvals or failure to comply with the terms and conditions of such permits, licenses or approvals would not, individually or in the aggregate, have a Material Adverse Effect;

(u) Other than as set forth or contemplated in the Pricing Prospectus, there are no costs or liabilities associated with Environmental Laws (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) which would, individually or in the aggregate, have a Material Adverse Effect;

(v) The Company and its subsidiaries own or possess licenses to all trademarks, service marks, trade names, trade dress, domain names (including all goodwill associated with the foregoing), patents, inventions, copyrights, software, know-how, trade secrets (including all registrations and applications for registration of any of the foregoing) and all other similar types of proprietary intellectual property rights (collectively, “Intellectual Property”) material to the conduct of their respective businesses as conducted or proposed to be conducted, as described in the Pricing Prospectus and, to the knowledge of the Company, the conduct of their respective businesses does not infringe, misappropriate or otherwise conflict in any material respect with any such rights of others. Except as would not reasonably be expected to have a Material Adverse Effect, neither the Company nor any of its subsidiaries has received any notice of any claim of infringement, misappropriation or conflict with any such rights of others, or any notice challenging the validity, scope, or enforceability of the Intellectual Property owned by the Company or any of its subsidiaries or the Company’s or any of its subsidiaries’ rights therein. Other than as set forth in the Pricing Prospectus or except as would not reasonably be expected to have a Material Adverse Effect, to the knowledge of the Company, no party has infringed, misappropriated or otherwise violated any Intellectual Property owned by the Company or any of its subsidiaries. Other than as described in the Pricing Prospectus, all Intellectual Property owned by the Company or its subsidiaries is owned solely by the Company or its subsidiaries and is owned free and clear of all liens, encumbrances, defects or other restrictions. All licenses pursuant to which any Intellectual Property is licensed by the Company or its subsidiaries are free and clear of all liens and free of any restrictions or defects that would conflict with the conduct of the business of the Company or any of its subsidiaries. To the knowledge of the Company, all Intellectual Property owned or licensed by the Company is valid and enforceable except where the lack of validity or enforceability would not reasonably be expected to have a Material Adverse Effect. Neither the Company nor any of its subsidiaries is subject to any judgment, order, writ, injunction or decree of any court or any federal, state, local,

foreign or other governmental department, commission, board, bureau, agency or instrumentality, domestic or foreign, or any arbitrator. Neither the Company nor any of its subsidiaries has entered into or become a party to any agreement made in settlement of any pending or threatened litigation which materially restricts or impairs its use of any Intellectual Property. The Company and its subsidiaries have taken reasonable steps in accordance with normal industry practice to maintain the confidentiality of all material trade secrets and confidential information owned, used or held for use by the Company or any of its subsidiaries and no such trade secrets or confidential information have been disclosed other than to employees, representatives and agents of the Company or any of its subsidiaries, or parties who are bound by written confidentiality agreements. All key employees and any other employees involved in the development of Intellectual Property for the Company or any of its subsidiaries have signed confidentiality and invention assignment agreements with the Company;

(w) With respect to stock options (the “Stock Options”) granted pursuant to the stock-based compensation plans of the Company and its subsidiaries (the “Company Stock Plans”), (i) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Code so qualifies, (ii) 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 (collectively, the “Board”) and any required stockholder approval by the necessary number of votes or written consents, (iii) the per share exercise price of each compensatory stock option granted by the Company reflects the per share fair market value of the Company’s Class A common stock on the date of grant, as determined by the Board, (iv) each such grant was made in accordance with the terms of the Company Stock Plans and (v) each such grant was properly accounted for in accordance with U.S. GAAP;

(x) (i) Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), for which the Company or any member of its “Controlled Group” (defined as any organization which is a member of a controlled group of corporations within the meaning of Section 414 of the Internal Revenue Code of 1986, as amended (the “Code”)) would have any liability (each, a “Plan”) has been maintained in compliance with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to, ERISA and the Code, except for noncompliance that could not reasonably be expected to result in material liability to the Company or its subsidiaries; (ii) no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any Plan excluding transactions effected pursuant to a statutory or administrative exemption that could reasonably be expected to result in a material liability to the Company or its subsidiaries; (iii) for each Plan that is subject to the

funding rules of Section 412 of the Code or Section 302 of ERISA, the minimum funding standard of Section 412 of the Code or Section 302 of ERISA, as applicable, has been satisfied (without taking into account any waiver thereof or extension of any amortization period) and is reasonably expected to be satisfied in the future (without taking into account any waiver thereof or extension of any amortization period); (iv) for each Plan that is an employee pension benefit plan within the meaning of Section 3(2) of ERISA, the difference between the aggregate fair value of the assets of such Plans and the aggregate present value of all benefits accrued under such Plans (determined based on those assumptions used to fund such Plan) is not materially greater than as set forth in the Pricing Prospectus; (v) no “reportable event” (within the meaning of Section 4043(c) of ERISA) has occurred or is reasonably expected to occur that either has resulted, or could reasonably be expected to result, in material liability to the Company or its subsidiaries; (vi) neither the Company nor any member of the Controlled Group has incurred, nor reasonably expects to incur, any liability under Title IV of ERISA (other than contributions to the Plan or premiums to the PBGC, in the ordinary course and without default) in respect of a Plan (including a “multiemployer plan”, within the meaning of Section 4001(a)(3) of ERISA); and (vii) there is no pending audit or investigation by the Internal Revenue Service, the U.S. Department of Labor, the Pension Benefit Guaranty Corporation or any other governmental agency or any foreign regulatory agency with respect to any Plan that could reasonably be expected to result in material liability to the Company or its subsidiaries. None of the following events has occurred or is reasonably likely to occur: (x) ,except as set forth in the Pricing Prospectus, a material increase in the aggregate amount of contributions required to be made to all Plans by the Company or its subsidiaries in the current fiscal year of the Company and its subsidiaries compared to the amount of such contributions made in the Company and its subsidiaries’ most recently completed fiscal year; or (y) a material increase in the Company and its subsidiaries’ “accumulated post-retirement benefit obligations” (within the meaning of FASB Accounting Standards Codification 715) compared to the amount of such obligations in the Company and its subsidiaries’ most recently completed fiscal year;

(y) The Company and its subsidiaries possess all licenses, permits, certificates and other authorizations from, and have made all declarations and filings with, all governmental authorities, required or necessary to own or lease, as the case may be, and to operate their respective properties and to carry on their respective businesses as now or proposed to be conducted as set forth in the Pricing Prospectus (“Permits”), except where the failure to obtain such Permits would not individually or in the aggregate have a Material Adverse Effect; the Company and subsidiaries have fulfilled and performed all of their respective obligations with respect to such Permits and no event has occurred which allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other impairment of the rights of the holder of any such Permit

except, in each case, as would not individually or in the aggregate have a Material Adverse Effect;

(z) Except as described in the Pricing Prospectus, there are no contracts, agreements or understandings between the Company or any subsidiary and any person granting such person the right to require the Company or any subsidiary to file a registration statement under the Act with respect to any securities of the Company or any subsidiary;

(aa) Neither the Company nor any of its subsidiaries or affiliates, nor any director, officer, or employee, nor, to the Company’s knowledge, any agent or representative of the Company or of any of its subsidiaries or affiliates, has taken or will take any action in furtherance of an offer, payment, promise to pay, or authorization or approval of the payment or giving of money, property, gifts or anything else of value, directly or indirectly, to any “government official” (including any officer or employee of a government or government-owned or controlled entity or of a public international organization, or any person acting in an official capacity for or on behalf of any of the foregoing, or any political party or party official or candidate for political office) to influence official action or secure an improper advantage; and the Company and its subsidiaries and affiliates have conducted their businesses in compliance with applicable anti-corruption laws and have instituted and maintain and will continue to maintain policies and procedures designed to promote and achieve compliance with such laws and with the representation and warranty contained herein;

(bb) The operations of the Company and its subsidiaries are and have been conducted at all times in material compliance with all applicable financial recordkeeping and reporting requirements, including those of the Bank Secrecy Act, as amended by Title III of the Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001 (USA PATRIOT Act), and the applicable anti-money laundering statutes of jurisdictions where the Company and its subsidiaries conduct business, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Anti-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 Anti-Money Laundering Laws is pending or, to the best knowledge of the Company, threatened; and

(cc) (i) The Company represents that neither the Company nor any of its subsidiaries, nor any director, officer, or employee thereof, nor, to the Company’s knowledge, any agent, affiliate or representative of the Company or any of its subsidiaries, is an individual or entity (“Person”) that is, or is owned or controlled by or acting for or on behalf of a Person that is:

(A) the subject of or target of any economic sanctions (i) administered or enforced by the U.S. Department of the Treasury’s Office of Foreign Assets Control (“OFAC”), economic sanctions imposed pursuant to the United Nations Security Council resolutions, or economic sanctions of the European Union, the United Kingdom or other relevant sanctions authority or (ii) a sanctions target under the U.S. Iran Sanctions Act, as amended or Executive Order 13590 (collectively, the “Sanctions”), nor

(B) located, organized or resident in a country or territory that is, or whose government is, the subject of the Sanctions (including, without limitation, Burma/Myanmar, Cuba, Iran, Libya, North Korea, Sudan and Syria).

(ii) The Company represents and covenants that it and its subsidiaries will not, directly or indirectly, use the proceeds it receives from the sale of the Shares, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other Person:

(A) with the purpose to fund or facilitate any activities or business of or with any Person or in any country or territory that, at the time of such funding or facilitation, is, or whose government is, the subject of or a target of the Sanctions; or

(B) in any other manner that will result in a violation of the laws and regulations governing the Sanctions by any Person (including any Person participating in the offering, whether as underwriter, advisor, investor or otherwise).

(iii) The Company represents and covenants that, except as disclosed in the Pricing Disclosure Package or the Company’s response letters to the SEC in connection with the offering of the Shares: (i) to its knowledge, for the past 5 years, it and its subsidiaries have not engaged in, and are not now engaged in, any dealings or transactions with any Person, or in any country or territory, that at the time of the dealing or transaction is or was, or whose government is or was, the subject of or the target of the Sanctions, and (ii) it and its subsidiaries will not engage in any dealings or transactions with any Person, or in any country or territory, that at the time of the dealing or transaction is, or whose government is, the subject of or a target of the Sanctions.

2. Each of the Selling Stockholders severally represents and warrants to, and agrees with, each of the Underwriters and the Company that:

(a) All consents, approvals, authorizations and orders necessary for the execution and delivery by such Selling Stockholder of this Agreement and the Power of Attorney and the Custody Agreement hereinafter referred to, and for the sale and delivery of the Shares to be sold by such Selling Stockholder hereunder, have been obtained; and such Selling Stockholder has full right, power and

authority to enter into this Agreement, the Power of Attorney and the Custody Agreement and to sell, assign, transfer and deliver the Shares to be sold by such Selling Stockholder hereunder;

(b) The sale of the Shares to be sold by such Selling Stockholder hereunder and the compliance by such Selling Stockholder with all of the provisions of this Agreement, the Power of Attorney and the Custody Agreement and the consummation of the transactions herein and therein contemplated will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any statute, indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which such Selling Stockholder is a party or by which such Selling Stockholder is bound or to which any of the property or assets of such Selling Stockholder is subject, nor will such action result in any violation of the provisions of the certificate of incorporation or bylaws or other organizational documents of such Selling Stockholder if such Selling Stockholder is a corporation, the Partnership Agreement of such Selling Stockholder if such Selling Stockholder is a partnership, the operating agreement or limited liability company agreement of such Selling Stockholder if such Selling Stockholder is a limited liability company or any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over such Selling Stockholder or the property of such Selling Stockholder;

(c) Such Selling Stockholder has, and immediately prior to the First Time of Delivery (as defined in Section 5 hereof) such Selling Stockholder will have, good and valid title to the Shares to be sold by such Selling Stockholder hereunder, free and clear of all liens, encumbrances, equities or claims; and, upon delivery of such Shares and payment therefor pursuant hereto, good and valid title to such Shares, free and clear of all liens, encumbrances, equities or claims, will pass to the several Underwriters;

(d) Such Selling Stockholder has not taken and will not take, directly or indirectly, any action which is designed to or which has constituted or which might reasonably be 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;

(e) To the extent that any statements or omissions made in the Registration Statement, any Preliminary Prospectus, the Prospectus or any amendment or supplement thereto are made in reliance upon and in conformity with written information furnished to the Company by such Selling Stockholder pursuant to such Selling Stockholder’s Stockholder Questionnaire (the “Selling Stockholder Provided Information”), such Preliminary Prospectus and the Registration Statement did, and the Prospectus and any further amendments or supplements to the Registration Statement and the Prospectus, when they become effective or are filed with the Commission, as the case may be, will conform in all material respects to the requirements of the Act and the rules and regulations of the Commission thereunder and will not contain any untrue

statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein not misleading;

(f) In order to document the Underwriters’ compliance with the reporting and withholding provisions of the Tax Equity and Fiscal Responsibility Act of 1982 with respect to the transactions herein contemplated, such Selling Stockholder will deliver to you prior to or at the First Time of Delivery (as defined in Section 5 hereof) a properly completed and executed United States Treasury Department Form W-9 (or other applicable form or statement specified by Treasury Department regulations in lieu thereof);

(g) In the case of Shares held in certificated form, certificates (the “Certificates”) and/or a duly executed stock power or powers (the “Stock Powers”) representing all of the Shares to be sold by such Selling Stockholder hereunder, or in the case of any Shares held in uncertificated form, a duly executed Stock Power representing all of the Shares to be sold by such Selling Stockholder, have been placed in custody under a Custody Agreement, in the form heretofore furnished to you (the “Custody Agreement”), duly executed and delivered by such Selling Stockholder to American Stock Transfer & Trust Company, LLC, as custodian (the “Custodian”), and such Selling Stockholder has duly executed and delivered a Power of Attorney, in the form heretofore furnished to you (the “Power of Attorney”), appointing the persons indicated in Schedule III hereto, and each of them, as such Selling Stockholder’s attorneys in fact (the “Attorneys in Fact”) with authority to execute and deliver this Agreement on behalf of such Selling Stockholder, to determine the purchase price to be paid by the Underwriters to the Selling Stockholders as provided in Section 3 hereof, to authorize the delivery of the Shares to be sold by such Selling Stockholder hereunder and otherwise to act on behalf of such Selling Stockholder in connection with the transactions contemplated by this Agreement and the Custody Agreement; and

(h) The Shares represented by the Certificates or Stock Powers, as applicable, held in custody for such Selling Stockholder under the Custody Agreement are subject to the interests of the Underwriters hereunder; the arrangements made by such Selling Stockholder for such custody, and the appointment by such Selling Stockholder of the Attorneys in Fact by the Power of Attorney, are to that extent irrevocable; the obligations of the Selling Stockholders hereunder shall not be terminated by operation of law, whether by the death or incapacity of any individual Selling Stockholder or, in the case of an estate or trust, by the death or incapacity of any executor or trustee or the termination of such estate or trust, or in the case of a partnership or corporation, by the dissolution of such partnership or corporation, or by the occurrence of any other event; if any individual Selling Stockholder or any such executor or trustee should die or become incapacitated, or if any such estate or trust should be terminated, or if any such partnership or corporation should be dissolved, or if any other such event should occur, before the delivery of the Shares to be sold by such Selling

Stockholder hereunder, the Certificates or Stock Powers, as applicable, representing the Shares to be sold by such Selling Stockholder shall be delivered by or on behalf of the Selling Stockholders in accordance with the terms and conditions of this Agreement and of the Custody Agreements; and actions taken by the Attorneys in Fact pursuant to the Powers of Attorney shall be as valid as if such death, incapacity, termination, dissolution or other event had not occurred, regardless of whether or not the Custodian, the Attorneys in Fact, or any of them, shall have received notice of such death, incapacity, termination, dissolution or other event.

3. Subject to the terms and conditions herein set forth, (a) the Company and each of the Selling Stockholders agree, severally and not jointly, to sell to each of the Underwriters, and each of the Underwriters agrees, severally and not jointly, to purchase from the Company and each of the Selling Stockholders, at a purchase price per share of $[·], the number of Firm Shares (to be adjusted by you so as to eliminate fractional shares) determined by multiplying the aggregate number of Shares to be sold by the Company and each of the Selling Stockholders as set forth opposite their respective names in Schedule III hereto by a fraction, the numerator of which is the aggregate number of Firm Shares to be purchased by such Underwriter as set forth opposite the name of such Underwriter in Schedule I hereto and the denominator of which is the aggregate number of Firm Shares to be purchased by all of the Underwriters from the Company and all of the Selling Stockholders hereunder and (b) in the event and to the extent that the Underwriters shall exercise the election to purchase Optional Shares as provided below, the Company agrees to sell to each of the Underwriters, and each of the Underwriters agrees, severally and not jointly, to purchase from the Company, at the purchase price per share set forth in clause (a) of this Section 3, that portion of the number of Optional Shares as to which such election shall have been exercised (to be adjusted by you so as to eliminate fractional shares) determined by multiplying such number of Optional Shares by a fraction the numerator of which is the maximum number of Optional Shares which such Underwriter is entitled to purchase as set forth opposite the name of such Underwriter in Schedule I hereto and the denominator of which is the maximum number of Optional Shares that all of the Underwriters are entitled to purchase hereunder.

The Company hereby grants to the Underwriters the right to purchase at their election up to [·] Optional Shares, at the purchase price per share set forth in the paragraph above, for the sole purpose of covering sales of shares in excess of the number of Firm Shares, provided that the purchase price per Optional Share shall be reduced by an amount per share equal to any dividends or distributions declared by the Company and payable on the Firm Shares but not payable on the Optional Shares. Any such election to purchase Optional Shares may be exercised only by written notice from you to the Company, given within a period of 30 calendar days after the date of this Agreement and setting forth the aggregate

number of Optional Shares to be purchased and the date on which such Optional Shares are to be delivered, as determined by you but in no event earlier than the First Time of Delivery (as defined in Section 5 hereof) or, unless you and the Company otherwise agree in writing, earlier than two or later than ten business days after the date of such notice.

4. Upon the authorization by you of the release of the Firm Shares, the several Underwriters propose to offer the Firm Shares for sale upon the terms and conditions set forth in the Prospectus.

5. (a) The Shares to be purchased by each Underwriter hereunder, in definitive form, and in such authorized denominations and registered in such names as the Representatives may request upon at least forty-eight hours’ prior notice to the Company and the Custodian shall be delivered by or on behalf of the Company and the Selling Stockholders to the Representatives, through the facilities of the Depository Trust Company (“DTC”), for the account of such Underwriter, against payment by or on behalf of such Underwriter of the purchase price therefor by wire transfer of Federal (same-day) funds to the account specified by the Company and the Custodian to the Representatives at least forty-eight hours in advance. The Company will cause the Certificates and Stock Powers representing the Shares to be made available for checking and packaging at least twenty-four hours prior to the Time of Delivery (as defined below) with respect thereto at the office of DTC or its designated custodian (the “Designated Office”). The time and date of such delivery and payment shall be, with respect to the Firm Shares, 9:30 a.m., New York City time, on [·], 2012 or such other time and date as the Representatives and the Company may agree upon in writing, and, with respect to the Optional Shares, 9:30 a.m., New York time, on the date specified by the Representatives in the written notice given by the Representatives of the Underwriters’ election to purchase such Optional Shares, or such other time and date as the Representatives and the Company may agree upon in writing. Such time and date for delivery of the Firm Shares is herein called the “First Time of Delivery”, such time and date for delivery of the Optional Shares, if not the First Time of Delivery, is herein called the “Second Time of Delivery”, and each such time and date for delivery is herein called a “Time of Delivery”.

(b) The documents to be delivered at each Time of Delivery by or on behalf of the parties hereto pursuant to Section 9 hereof, including the cross receipt for the Shares and any additional documents requested by the Underwriters pursuant to Section 9(m) hereof, will be delivered at the offices of Davis Polk & Wardwell LLP, 1600 El Camino Real, Menlo Park, California 94025 (the “Closing Location”), and the Shares will be delivered at the Designated Office, all at such Time of Delivery. A meeting will be held at the Closing Location at [· p.m.], New York City time, on the New York Business Day next preceding such Time of Delivery, at which meeting the final drafts of the documents to be delivered pursuant to the preceding sentence will be available for review by the

parties hereto. For the purposes of this Section 5, “New York Business Day” shall mean each Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which banking institutions in New York City are generally authorized or obligated by law or executive order to close.

6. The Company agrees with each of the Underwriters:

(a) To prepare the Prospectus in a form approved by you and to file such Prospectus pursuant to Rule 424(b) under the Act not later than the Commission’s close of business on the second business day following the execution and delivery of this Agreement, or, if applicable, such earlier time as may be required by Rule 430A(a)(3) under the Act; to make no further amendment or any supplement to the Registration Statement or the Prospectus prior to the last Time of Delivery which shall be disapproved by you promptly after reasonable notice thereof; to advise you, promptly after it receives notice thereof, of the time when any amendment to the Registration Statement has been filed or becomes effective or any amendment or supplement to the Prospectus has been filed and to furnish you with copies thereof; to file promptly all material required to be filed by the Company with the Commission pursuant to Rule 433(d) under the Act; to advise you, promptly after it receives notice thereof, of the issuance by the Commission of any stop order or of any order preventing or suspending the use of any Preliminary Prospectus or other prospectus in respect of the Shares, of the suspension of the qualification of the Shares for offering or sale in any jurisdiction, of the initiation or threatening of any proceeding for any such purpose, or of any request by the Commission for the amending or supplementing of the Registration Statement or the Prospectus or for additional information; and, in the event of the issuance of any stop order or of any order preventing or suspending the use of any Preliminary Prospectus or other prospectus relating to the Shares or suspending any such qualification, to promptly use its best efforts to obtain the withdrawal of such order;

(b) Promptly from time to time to take such action as you may reasonably request to qualify the Shares for offering and sale under the securities laws of such jurisdictions as you may request and to comply with such laws so as to permit the continuance of sales and dealings therein in such jurisdictions for as long as may be necessary to complete the distribution of the Shares, provided that in connection therewith the Company shall not be required to qualify as a foreign corporation or to file a general consent to service of process in any jurisdiction;

(c) Prior to 10:00 a.m., New York City time, on the New York Business Day next succeeding the date of this Agreement and from time to time, to furnish the Underwriters with written and electronic copies of the Prospectus in New York City in such quantities as you may reasonably request, and, if the delivery of a prospectus (or in lieu thereof, the notice referred to in Rule 173(a) under the Act) is required at any time prior to the expiration of nine months after the time of issue

of the Prospectus in connection with the offering or sale of the Shares and if at such time any event shall have occurred as a result of which the Prospectus as then amended or supplemented 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 when such Prospectus (or in lieu thereof, the notice referred to in Rule 173(a) under the Act) is delivered, not misleading, or, if for any other reason it shall be necessary during such same period to amend or supplement the Prospectus in order to comply with the Act, to notify you and upon your request to prepare and furnish without charge to each Underwriter and to any dealer in securities as many written and electronic copies as you may from time to time reasonably request of an amended Prospectus or a supplement to the Prospectus which will correct such statement or omission or effect such compliance; and in case any Underwriter is required to deliver a prospectus (or in lieu thereof, the notice referred to in Rule 173(a) under the Act) in connection with sales of any of the Shares at any time nine months or more after the time of issue of the Prospectus, upon your request but at the expense of such Underwriter, to prepare and deliver to such Underwriter as many written and electronic copies as you may request of an amended or supplemented Prospectus complying with Section 10(a)(3) of the Act;

(d) To make generally available to its securityholders as soon as practicable, but in any event not later than sixteen months after the effective date of the Registration Statement (as defined in Rule 158(c) under the Act), an earnings statement of the Company and its subsidiaries (which need not be audited) complying with Section 11(a) of the Act and the rules and regulations of the Commission thereunder (including, at the option of the Company, Rule 158);

(e) During the period beginning from the date hereof and continuing to and including the date 180 days after the date of the Prospectus (the “Lock-Up Period”), not to (i) offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise transfer or dispose of, directly or indirectly, or file with the Commission a registration statement under the Act relating to, any securities of the Company that are substantially similar to the Shares, including but not limited to any options or warrants to purchase shares of Stock or any securities that are convertible into or exchangeable for, or that represent the right to receive, Stock or any such substantially similar securities, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Stock or any such other securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Stock or such other securities, in cash or otherwise, without the prior written consent of each of the Representatives (other than (a) the sale and issuance of the Shares to be sold hereunder, (b) grants of Stock Options or stock appreciation rights pursuant to the terms of the Company Stock Plans in effect on the date hereof and disclosed in the Pricing Prospectus or issuances of

securities pursuant to the exercise of such Stock Options or stock appreciation rights or the exercise of any Stock Options or stock appreciation rights outstanding on the date hereof, (c) issuances of securities upon the conversion or exchange of convertible or exchangeable securities outstanding as of the date of this Agreement or (d) the issuance by the Company of shares of Stock representing up to 5% of the outstanding shares of all classes of the Company’s common stock as of the consummation of the offering of the Shares issued and issuable in full or partial consideration of any acquisition or strategic investment, provided that the holders of such shares of Stock received in such acquisition or strategic investment sign and deliver to the Representatives lockup letters in the same form as delivered to the Representatives pursuant to Section 9(k) hereof); provided, however, that if (1) during the last 17 days of the initial Lock-Up Period, the Company releases earnings results or announces material news or a material event or (2) prior to the expiration of the initial Lock-Up Period, the Company announces that it will release earnings results during the 15-day period following the last day of the initial Lock-Up Period, then in each case the Lock-Up Period will be automatically extended until the expiration of the 18-day period beginning on the date of release of the earnings results or the announcement of the material news or material event, as applicable, unless each of the Representatives waives, in writing, such extension; the Company will provide each of the Representatives and each party subject to the Lock-Up Period pursuant to the lockup letters described in Section 9(k) with prior notice of any such announcement that gives rise to an extension of the Lock-Up Period;

(f) To furnish to its stockholders as soon as practicable after the end of each fiscal year an annual report (including a balance sheet and statements of income, stockholders’ equity and cash flows of the Company and its consolidated subsidiaries certified by independent public accountants) and, as soon as practicable after the end of each of the first three quarters of each fiscal year (beginning with the fiscal quarter ending after the effective date of the Registration Statement), to make available to its stockholders consolidated summary financial information of the Company and its subsidiaries for such quarter in reasonable detail;

(g) During a period of five years from the effective date of the Registration Statement, to furnish to you copies of all reports or other communications (financial or other) furnished to stockholders, and to deliver to you (i) as soon as they are available, copies of any reports and financial statements furnished to or filed with the Commission or any national securities exchange on which any class of securities of the Company is listed; and (ii) such additional information concerning the business and financial condition of the Company as you may from time to time reasonably request (such financial statements to be on a consolidated basis to the extent the accounts of the Company and its subsidiaries are consolidated in reports furnished to its stockholders generally or to the Commission) provided that the Company shall not

be required to provide information (1) that is available on the Company’s website or through EDGAR or (2) the provision of which would require public disclosure by the Company under Regulation FD;

(h) To use the net proceeds received by it from the sale of the Shares pursuant to this Agreement in the manner specified in the Pricing Prospectus under the caption “Use of Proceeds”;

(i) To use its best efforts to list, subject to notice of issuance, the Shares on the NASDAQ Global Market or Global Select Market (“NASDAQ”);

(j) To file with the Commission such information on Form 10-Q or Form 10-K as may be required by Rule 463 under the Act;

(k) If the Company elects to rely upon Rule 462(b), the Company shall file a Rule 462(b) Registration Statement with the Commission in compliance with Rule 462(b) by 10:00 P.M., Washington, D.C. time, on the date of this Agreement, and the Company shall at the time of filing either pay to the Commission the filing fee for the Rule 462(b) Registration Statement or give irrevocable instructions for the payment of such fee pursuant to Rule 111(b) under the Act; and

(l) Upon request of any Underwriter, to furnish, or cause to be furnished, to such Underwriter an electronic version of the Company’s trademarks, servicemarks and corporate logo for use on the website, if any, operated by such Underwriter for the purpose of facilitating the on-line offering of the Shares (the “License”); provided, however, that the License shall be used solely for the purpose described above, is granted without any fee and may not be assigned or transferred.

7. (a) The Company and each of the Selling Stockholders each represent and agree that, without the prior consent of the Representatives, it has not made and will not make any offer relating to the Shares that would constitute a “free writing prospectus” as defined in Rule 405 under the Act; each Underwriter represents and agrees that, without the prior consent of the Company and the Representatives, it has not made and will not make any offer relating to the Shares that would constitute a free writing prospectus; any such free writing prospectus the use of which has been consented to by the Company and the Representatives is listed on Schedule II(a) or Schedule II(b) hereto;

(b) The Company has complied and will comply with the requirements of Rule 433 under the Act applicable to any Issuer Free Writing Prospectus, including timely filing with the Commission or retention where required and legending; and the Company represents that it has satisfied and agrees that it will satisfy the conditions under Rule 433 under the Act to avoid a requirement to file with the Commission any electronic road show; and

(c) The Company agrees that if at any time following issuance of an Issuer Free Writing Prospectus any event occurred or occurs as a result of which

such Issuer Free Writing Prospectus would conflict with the information in the Registration Statement, the Pricing 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 then prevailing, not misleading, the Company will give prompt notice thereof to the Representatives and, if requested by the Representatives, will prepare and furnish without charge to each Underwriter an Issuer Free Writing Prospectus or other document which will correct such conflict, statement or omission; provided, however, that this covenant shall not apply to any statements or omissions in an Issuer Free Writing Prospectus made in reliance upon and in conformity with information furnished in writing to the Company by an Underwriter through the Representatives expressly for use therein.

8. The Company covenants and agrees with the several Underwriters that the Company will 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, reproduction and filing of the Registration Statement, any Preliminary Prospectus, any Issuer Free Writing Prospectus and the Prospectus and amendments and supplements thereto and the mailing and delivering of copies thereof to the Underwriters and dealers; (ii) the cost of printing or producing any Agreement among Underwriters, this Agreement, the Blue Sky Memorandum, closing documents (including any compilations thereof) and any other documents necessary in connection with the offering, purchase, sale and delivery of the Shares; (iii) all expenses in connection with the qualification of the Shares for offering and sale under state securities laws as provided in Section 6(b) hereof, including the documented fees and disbursements of counsel for the Underwriters in connection with such qualification and in connection with the Blue Sky survey; (iv) all fees and expenses in connection with listing the Shares on NASDAQ; (v) the filing fees incident to, and the fees and disbursements of counsel for the Underwriters in connection with, any required review by the Financial Industry Regulatory Authority, Inc. or FINRA, of the terms of the sale of the Shares; (vi) the cost of preparing stock certificates; (vi) the cost and charges of any transfer agent or registrar; and (vii) all other costs and expenses incident to the performance of its obligations hereunder which are not otherwise specifically provided for in this Section. It is understood, however, that, except as provided in this Section and Sections 10 and 13 hereof, the Underwriters will pay all of their own costs and expenses, including the fees of their counsel, stock transfer taxes on resale of any of the Shares by them, and any advertising expenses connected with any offers they may make.

9. The obligations of the Underwriters hereunder, as to the Shares to be delivered at each Time of Delivery, shall be subject, in their discretion, to the

condition that all representations and warranties and other statements of the Company and of the Selling Stockholders herein are, at and as of such Time of Delivery, true and correct, the condition that the Company and the Selling Stockholders shall have performed all of its and their obligations hereunder theretofore to be performed, and the following additional conditions:

(a) The Prospectus shall have been filed with the Commission pursuant to Rule 424(b) under the Act within the applicable time period prescribed for such filing by the rules and regulations under the Act and in accordance with Section 6(a) hereof; all material required to be filed by the Company pursuant to Rule 433(d) under the Act shall have been filed with the Commission within the applicable time period prescribed for such filing by Rule 433; if the Company has elected to rely upon Rule 462(b) under the Act, the Rule 462(b) Registration Statement shall have become effective by 10:00 P.M., Washington, D.C. time, on the date of this Agreement; no stop order suspending the effectiveness of the Registration Statement or any part thereof shall have been issued and no proceeding for that purpose shall have been initiated or threatened by the Commission; no stop order suspending or preventing the use of the Prospectus or any Issuer Free Writing Prospectus shall have been initiated or threatened by the Commission; and all requests for additional information on the part of the Commission shall have been complied with to your reasonable satisfaction;

(b) Davis Polk & Wardwell LLP, counsel for the Underwriters, shall have furnished to you such written opinion or opinions (a form of each such opinion is attached as Annex II(a) hereto), dated such Time of Delivery, in form and substance satisfactory to you, with respect to such matters as you may reasonably request, and such counsel shall have received such papers and information as they may reasonably request to enable them to pass upon such matters;

(c) Stoel Rives LLP, counsel for the Company, shall have furnished to you its written opinion, dated such Time of Delivery, in substantially the form set forth in Annex II(b) hereto.

(d) The respective counsel for each of the Company’s Significant Subsidiaries shall have furnished to you their written opinions, dated such Time of Delivery, in substantially the form set forth in Annex II(c) hereto.

(e) The respective counsel for each of the Selling Stockholders, as indicated in Schedule III hereto, each shall have furnished to you their written opinion with respect to each of the Selling Stockholders for whom they are acting as counsel, substantially in the form set forth in Annex II(d) hereto.

(f) On the date of the Prospectus at a time prior to the execution of this Agreement, at 9:30 a.m., New York City time, on the effective date of any post-effective amendment to the Registration Statement filed subsequent to the date of this Agreement and also at each Time of Delivery, PricewaterhouseCoopers LLP shall have furnished to you a letter or letters, dated the respective dates of delivery thereof, in form and substance satisfactory to you, to the effect set forth in Annex I-A hereto (the executed copy of the letter delivered prior to the execution of this Agreement is attached as Annex I(a) hereto and a draft of the form of letter to be delivered on the effective date of any post-effective amendment to the Registration Statement and as of each Time of Delivery is attached as Annex I(b) hereto);

(g) (i) Neither the Company nor any of its subsidiaries shall have sustained since the date of the latest audited financial statements included in the Pricing Prospectus any loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor dispute or court or governmental action, order or decree, otherwise than as set forth or contemplated in the Pricing Prospectus, and (ii) since the respective dates as of which information is given in the Pricing Prospectus there shall not have been any change in the capital stock or long term debt of the Company or any of its subsidiaries or any change, or any development involving a prospective change, in or affecting the general affairs, management, financial position, stockholders’ equity or results of operations of the Company and its subsidiaries, otherwise than as set forth or contemplated in the Pricing Prospectus, the effect of which, in any such case described in clause (i) or (ii), is in your judgment so material and adverse as to make it impracticable or inadvisable to proceed with the public offering or the delivery of the Shares being delivered at such Time of Delivery on the terms and in the manner contemplated in the Prospectus;

(h) On or after the Applicable Time (i) no downgrading shall have occurred in the rating accorded the Company’s debt securities, if any, by any “nationally recognized statistical rating organization”, as that term is defined by the Commission for purposes of Rule 436(g)(2) under the Act, and (ii) no 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;

(i) On or after the Applicable Time there shall not have occurred any of the following: (i) a suspension or material limitation in trading in securities generally on the New York Stock Exchange or on NASDAQ; (ii) a suspension or material limitation in trading in the Company’s securities on NASDAQ; (iii) a general moratorium on commercial banking activities declared by either Federal or New York State authorities or a material

disruption in commercial banking or securities settlement or clearance services in the United States; (iv) the outbreak or escalation of hostilities involving the United States or the declaration by the United States of a national emergency or war; or (v) the occurrence of any other calamity or crisis or any change in financial, political or economic conditions in the United States or elsewhere, if the effect of any such event specified in clause (iv) or (v) in your judgment makes it impracticable or inadvisable to proceed with the public offering or the delivery of the Shares being delivered at such Time of Delivery on the terms and in the manner contemplated in the Prospectus;

(j) The Shares to be sold at such Time of Delivery shall have been duly listed, subject to notice of issuance, on NASDAQ;

(k) The Company shall have obtained and delivered to the Underwriters executed copies of an agreement from each of the Company’s directors and executive officers and those other persons listed on Schedule V, substantially to the effect set forth in Annex III hereof in form and substance satisfactory to you;

(l)The Company shall have complied with the provisions of Section 6(c) hereof with respect to the furnishing of prospectuses on the New York Business Day next succeeding the date of this Agreement; and

(m) The Company and the Selling Stockholders shall have furnished or caused to be furnished to you at such Time of Delivery certificates of officers of the Company and of the Selling Stockholders, respectively, satisfactory to you as to the accuracy of the representations and warranties of the Company and the Selling Stockholders, respectively, herein at and as of such Time of Delivery, as to the performance by the Company and the Selling Stockholders of all of their respective obligations hereunder to be performed at or prior to such Time of Delivery, and as to such other matters as you may reasonably request, and the Company shall have furnished or caused to be furnished certificates as to the matters set forth in subsections (a) and (g) of this Section.

10. (a) The Company will indemnify and hold harmless each Underwriter against any losses, claims, damages or liabilities, joint or several, to which such Underwriter may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, any Issuer Free Writing Prospectus or any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Act, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and will

reimburse each Underwriter for any reasonably documented legal or other expenses reasonably incurred by such Underwriter in connection with investigating or defending any such action or claim as such expenses are incurred; provided, however, that the Company shall not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use therein.

(b) Each of the Selling Stockholders, severally and not jointly, will indemnify and hold harmless each Underwriter against any losses, claims, damages or liabilities to which such Underwriter may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus, the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, or any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Act, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in the Registration Statement, any Preliminary Prospectus, the Prospectus or any such amendment or supplement thereto, any Issuer Free Writing Prospectus, or any such “issuer information” in reliance upon and in conformity with such Selling Stockholder Provided Information; and will reimburse each Underwriter for any reasonably documented legal or other expenses reasonably incurred by such Underwriter in connection with investigating or defending any such action or claim as such expenses are incurred; provided, however, that such Selling Stockholder shall not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus or any such amendment or supplement thereto, or any Issuer Free Writing Prospectus, in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representative expressly for use therein; provided, further, that the liability of a Selling Stockholder pursuant to this subsection (b) hereof shall not exceed the total proceeds (net of underwriting discounts and commissions, but before deducting other expenses) paid by the Underwriters for the Shares to such Selling Stockholder or the Custodian for the benefit of such

Selling Stockholder for the Shares (including any Option Shares) sold by such Selling Stockholder.

(c) Each Underwriter will indemnify and hold harmless the Company and each Selling Stockholder against any losses, claims, damages or liabilities to which the Company or such Selling Stockholder may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in the Registration Statement, any Preliminary Prospectus, the Pricing Prospectus or the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, in reliance upon and in conformity with written information furnished to the Company by such Underwriter through the Representatives expressly for use therein; and will reimburse the Company and each Selling Stockholder for any reasonably documented legal or other expenses reasonably incurred by the Company and each Selling Stockholder in connection with investigating or defending any such action or claim as such expenses are incurred.

(d) Promptly after receipt by an indemnified party under subsection (a), (b) or (c) above of notice of the commencement of any action, such indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under such subsection, notify the indemnifying party in writing of the commencement thereof; but the omission so to notify the indemnifying party shall not relieve it from any liability which it may have to any indemnified party otherwise than under such subsection, except to the extent the indemnifying party is materially prejudiced by such omission. In case any such action shall be brought against any indemnified party and it shall notify the indemnifying party of the commencement thereof, the indemnifying party shall be entitled to participate therein and, to the extent that it shall wish, jointly with any other indemnifying party similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party (who shall not, except with the consent of the indemnified party, be counsel to the indemnifying party), and, after notice from the indemnifying party to such indemnified party of its election so to assume the defense thereof, the indemnifying party shall not be liable to such indemnified party under such subsection for any reasonably documented legal expenses of other counsel or any other expenses, in each case subsequently incurred by such indemnified party, in connection with the defense thereof other than reasonable costs of investigation. No indemnifying party shall, without the written consent of

the indemnified party, effect the settlement or compromise of, or consent to the entry of any judgment with respect to, any pending or threatened action or claim in respect of which indemnification or contribution may be sought hereunder (whether or not the indemnified party is an actual or potential party to such action or claim) unless such settlement, compromise or judgment (i) includes an unconditional release of the indemnified party from all liability arising out of such action or claim and (ii) does not include a statement as to or an admission of fault, culpability or a failure to act, by or on behalf of any indemnified party.

(e) If the indemnification provided for in this Section 10 is unavailable to or insufficient to hold harmless an indemnified party under subsection (a), (b) or (c) above in respect of any losses, claims, damages or liabilities (or actions in respect thereof) referred to therein, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party as a result of such losses, claims, damages or liabilities (or actions in respect thereof) in such proportion as is appropriate to reflect the relative benefits received by the Company and the Selling Stockholders on the one hand and the Underwriters on the other from the offering of the Shares. If, however, the allocation provided by the immediately preceding sentence is not permitted by applicable law or if the indemnified party failed to give the notice required under subsection (d) above, then each indemnifying party shall contribute to such amount paid or payable by such indemnified party in such proportion as is appropriate to reflect not only such relative benefits but also the relative fault of the Company and the Selling Stockholders on the one hand and the Underwriters on the other in connection with the statements or omissions which resulted in such losses, claims, damages or liabilities (or actions in respect thereof), as well as any other relevant equitable considerations. The relative benefits received by the Company and the Selling Stockholders on the one hand and the Underwriters on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company and the Selling Stockholders 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. The relative fault 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 and the Selling Stockholders on the one hand or the Underwriters on the other and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The Company, each of the Selling Stockholders and the Underwriters agree that it would not be just and equitable if contributions pursuant to this subsection (e) were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to above in this subsection (e). The amount paid or payable by an indemnified party as a result of the losses, claims, damages

or liabilities (or actions in respect thereof) referred to above in this subsection (e) shall be deemed to include any documented 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 subsection (e), (i) no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Shares underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages which such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission; and (ii) in no event shall a Selling Stockholder be required to contribute any amount in excess of the amount by which (A) the total proceeds (net of underwriting discounts and commissions, but before deducting other expenses) paid by the Underwriters for the Shares to such Selling Stockholder or the Custodian for the benefit of such Selling Stockholder for the Shares (including any Option Shares) sold by such Selling Stockholder pursuant to this Agreement exceeds (B) the amount of any damages that such Selling Stockholder has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations in this subsection (e) to contribute are several in proportion to their respective underwriting obligations and not joint. Further, the Selling Stockholders’ obligations to contribute pursuant to this subsection (e) are several and not joint.

(f) The obligations of the Company and the Selling Stockholders under this Section 10 shall be in addition to any liability which the Company and the Selling Stockholders may otherwise have and shall extend, upon the same terms and conditions, to each person, if any, who controls any Underwriter within the meaning of the Act and each broker-dealer affiliate of any Underwriter; and the obligations of the Underwriters under this Section 10 shall be in addition to any liability which the respective Underwriters may otherwise have and shall extend, upon the same terms and conditions, to each officer and director of the Company (including any person who, with his or her consent, is named in the Registration Statement as about to become a director of the Company) and to each person, if any, who controls the Company or any Selling Stockholder within the meaning of the Act.

11. (a) If any Underwriter shall default in its obligation to purchase the Shares which it has agreed to purchase hereunder at a Time of Delivery, you may in your discretion arrange for you or another party or other parties to purchase such Shares on the terms contained herein. If within thirty-six hours after such default by any Underwriter you do not arrange for the purchase of such Shares, then the Company and the Selling Stockholders shall be entitled to a further period of thirty-six hours within which to procure another party or other parties

satisfactory to you to purchase such Shares on such terms. In the event that, within the respective prescribed periods, you notify the Company and the Selling Stockholders that you have so arranged for the purchase of such Shares, or the Company and the Selling Stockholders notify you that they have so arranged for the purchase of such Shares, you or the Company and the Selling Stockholders shall have the right to postpone such Time of Delivery for a period of not more than seven days, in order to effect whatever changes may thereby be made necessary in the Registration Statement or the Prospectus, or in any other documents or arrangements, and the Company agrees to file promptly any amendments or supplements to the Registration Statement or the Prospectus which in your opinion may thereby be made necessary. The term “Underwriter” as used in this Agreement shall include any person substituted under this Section with like effect as if such person had originally been a party to this Agreement with respect to such Shares.

(b) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by you and the Company and the Selling Stockholders as provided in subsection (a) above, the aggregate number of such Shares which remains unpurchased does not exceed one-eleventh of the aggregate number of all the Shares to be purchased at such Time of Delivery, then the Company and the Selling Stockholders shall have the right to require each non-defaulting Underwriter to purchase the number of Shares which such Underwriter agreed to purchase hereunder at such Time of Delivery and, in addition, to require each non-defaulting Underwriter to purchase its pro rata share (based on the number of Shares which such Underwriter agreed to purchase hereunder) of the Shares of such defaulting Underwriter or Underwriters for which such arrangements have not been made; but nothing herein shall relieve a defaulting Underwriter from liability for its default.

(c) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by you and the Company and the Selling Stockholders as provided in subsection (a) above, the aggregate number of such Shares which remains unpurchased exceeds one-eleventh of the aggregate number of all the Shares to be purchased at such Time of Delivery, or if the Company and the Selling Stockholders shall not exercise the right described in subsection (b) above to require non-defaulting Underwriters to purchase Shares of a defaulting Underwriter or Underwriters, then this Agreement (or, with respect to the Second Time of Delivery, the obligations of the Underwriters to purchase and of the Company to sell the Optional Shares) shall thereupon terminate, without liability on the part of any non-defaulting Underwriter or the Company or the Selling Stockholders, except for the expenses to be borne by the Company and the Underwriters as provided in Section 8 hereof and the indemnity and contribution agreements in Section 10 hereof; but nothing herein shall relieve a defaulting Underwriter from liability for its default.

12. The respective indemnities, agreements, representations, warranties and other statements of the Company, the Selling Stockholders and the several Underwriters, as set forth in this Agreement or made by or on behalf of them, respectively, pursuant to this Agreement, shall remain in full force and effect, regardless of any investigation (or any statement as to the results thereof) made by or on behalf of any Underwriter or any controlling person of any Underwriter, or the Company, or any of the Selling Stockholders, or any officer or director or controlling person of the Company, or any controlling person of any Selling Stockholder, and shall survive delivery of and payment for the Shares.

13. If this Agreement shall be terminated pursuant to Section 11 hereof, neither the Company nor the Selling Stockholders shall then be under any liability to any Underwriter except as provided in Sections 8 and 10 hereof; but, if for any other reason, any Shares are not delivered by or on behalf of the Company and the Selling Stockholders as provided herein, the Company will reimburse the Underwriters through you for all out-of-pocket expenses approved in writing by you, including fees and disbursements of counsel, reasonably incurred by the Underwriters in making preparations for the purchase, sale and delivery of the Shares not so delivered, but the Company and the Selling Stockholders shall then be under no further liability to any Underwriter in respect of the Shares not so delivered except as provided in Sections 8 and 10 hereof.

14. In all dealings hereunder, you shall act on behalf of each of the Underwriters, and the parties hereto shall be entitled to act and rely upon any statement, request, notice or agreement on behalf of any Underwriter made or given by you; and in all dealings with any Selling Stockholder hereunder, you and the Company shall be entitled to act and rely upon any statement, request, notice or agreement on behalf of such Selling Stockholder made or given by any or all of the Attorneys in Fact for such Selling Stockholder.

All statements, requests, notices and agreements hereunder shall be in writing, and if to the Underwriters shall be delivered or sent by mail, telex or facsimile transmission to each of the Representatives in care of (a) Goldman, Sachs & Co., 200 West Street, New York, New York 10282-2198, Attention: Registration Department and (b) Morgan Stanley & Co. LLC, 1585 Broadway, New York, New York 10036-8293, Attention: Equity Syndicate Desk; if to any Selling Stockholder shall be delivered or sent by mail, telex or facsimile transmission to counsel for such Selling Stockholder at its address set forth in Schedule III hereto; and if to the Company shall be delivered or sent by mail, telex or facsimile transmission to the address of the Company set forth in the Registration Statement, Attention: Secretary; provided, however, that any notice to an Underwriter pursuant to Section 10(d) hereof shall be delivered or sent by mail, telex or facsimile transmission to such Underwriter at its address set forth in its Underwriters’ Questionnaire, or telex constituting such Questionnaire, which address will be supplied to the Company or the Selling Stockholders by you upon request; provided, however, that notices under subsection 6(e) shall be in writing,

and if to the Underwriters shall be delivered or sent by mail, telex or facsimile transmission to each of the Representatives at (i) Goldman, Sachs & Co., 200 West Street, New York, New York 10282-2198, Attention: Control Room and (ii) Morgan Stanley & Co. LLC, 1585 Broadway, New York, New York 10036-8293, Attention: Equity Syndicate Desk. Any such statements, requests, notices or agreements shall take effect upon receipt thereof.

In accordance with the requirements of the USA Patriot Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)), the underwriters are required to obtain, verify and record information that identifies their respective clients, including the Company, which information may include the name and address of their respective clients, as well as other information that will allow the underwriters to properly identify their respective clients.

15. This Agreement shall be binding upon, and inure solely to the benefit of, the Underwriters, the Company and the Selling Stockholders, and, to the extent provided in Sections 10 and 12 hereof, the officers and directors of the Company and each person who controls the Company, any Selling Stockholder or any Underwriter, and their respective heirs, executors, administrators, successors and assigns, and no other person shall acquire or have any right under or by virtue of this Agreement. No purchaser of any of the Shares from any Underwriter shall be deemed a successor or assign by reason merely of such purchase.

16. Time shall be of the essence of this Agreement. As used herein, the term “business day” shall mean any day when the Commission’s office in Washington, D.C. is open for business.

17. Each of the Company and each Selling Stockholder, acknowledges and agrees that (i) the purchase and sale of the Shares pursuant to this Agreement is an arm’s-length commercial transaction between the Company and the Selling Stockholders, on the one hand, and the several Underwriters, on the other, (ii) in connection therewith and with the process leading to such transaction each Underwriter is acting solely as a principal and not the agent or fiduciary of the Company or any Selling Stockholder, (iii) no Underwriter has assumed an advisory or fiduciary responsibility in favor of the Company or any Selling Stockholder with respect to the offering contemplated hereby or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company or any Selling Stockholder on other matters) or any other obligation to the Company or any Selling Stockholder except the obligations expressly set forth in this Agreement and (iv) the Company and each Selling Stockholder have consulted their own legal and financial advisors to the extent they deemed appropriate. The Company and each of the Selling Stockholders agree that they will not claim that the Underwriters, or any of them, have rendered advisory services of any nature or respect, or owes a fiduciary or similar duty to the Company or any Selling Stockholder, in connection with such transaction or the process leading thereto.

18. This Agreement supersedes all prior agreements and understandings (whether written or oral) among the Company, the Selling Stockholders and the Underwriters, or any of them, with respect to the subject matter hereof.

19. THIS AGREEMENT AND ANY MATTERS RELATED TO THIS TRANSACTION SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO PRINCIPLES OF CONFLICT OF LAWS THAT WOULD RESULT IN THE APPLICATION OF ANY LAW OTHER THAN THE LAWS OF THE STATE OF NEW YORK. The Company and each Selling Stockholder agree that any suit or proceeding arising in respect of this agreement or our engagement will be tried exclusively in the U.S. District Court for the Southern District of New York or, if that court does not have subject matter jurisdiction, in any state court located in The City and County of New York and the Company and each Selling Stockholder agree to submit to the jurisdiction of, and to venue in, such courts.

20. The Company, each Selling Stockholder and each of the Underwriters hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

21. This Agreement may be executed by any one or more of the parties hereto in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same instrument.

22. Notwithstanding anything herein to the contrary, the Company and the Selling Stockholders are authorized to disclose to any persons the U.S. federal and state income tax treatment and tax structure of the potential transaction and all materials of any kind (including tax opinions and other tax analyses) provided to the Company and the Selling Stockholders relating to that treatment and structure, without the Underwriters imposing any limitation of any kind. However, any information relating to the tax treatment and tax structure shall remain confidential (and the foregoing sentence shall not apply) to the extent necessary to enable any person to comply with securities laws. For this purpose, “tax structure” is limited to any facts that may be relevant to that treatment.

If the foregoing is in accordance with your understanding, please sign and return to us six counterparts hereof, and upon the acceptance hereof by you, on behalf of each of the Underwriters, this letter and such acceptance hereof shall constitute a binding agreement among each of the Underwriters, the Company and each of the Selling Stockholders. It is understood that your acceptance of this letter on behalf of each of the Underwriters is pursuant to the authority set forth in a form of Agreement among Underwriters, the form of which shall be submitted to the Company and the Selling Stockholders for examination upon

request, but without warranty on your part as to the authority of the signers thereof.

Any person executing and delivering this Agreement as Attorney in Fact for a Selling Stockholder represents by so doing that he has been duly appointed as Attorney in Fact by such Selling Stockholder pursuant to a validly existing and binding Power of Attorney which authorizes such Attorney in Fact to take such action.

	Very truly yours,

	ESCO CORPORATION


	By:
		Name:
		Title:

	THE SELLING STOCKHOLDERS NAMED IN SCHEDULE III HERETO


	By:
		Name:
		Title: Attorney in Fact

Accepted as of the date hereof:

GOLDMAN, SACHS & CO.


By:
(Goldman, Sachs & Co.)

MORGAN STANLEY & CO. LLC


By:
	Name:
	Title:

	On behalf of each of the Underwriters

SCHEDULE I

		Number of
		Optional
		Shares to
	Total	be
	Number of	Purchased
	Firm	if
	Shares to	Maximum
	be	Option
Underwriter	Purchased	Exercised

Goldman, Sachs & Co.
Morgan Stanley & Co. LLC
Wells Fargo Securities, LLC
Robert W. Baird & Co. Incorporated
KeyBanc Capital Markets Inc.
BMO Capital Markets Corp.

Total

SCHEDULE II

(a) Issuer Free Writing Prospectuses not included in the Pricing Disclosure Package

(b) Materials other than the Pricing Prospectus that comprise the Pricing Disclosure Package

SCHEDULE III

		Total Number of
		Shares
		to be Sold
The Company
The Selling Stockholders(a):

Total

(a) With the exception of T&J Anderson Family Investments, LLC, the Selling Stockholders are represented by Whalen LLP, 19000 MacArthur Blvd., Ste 600, Irvine, CA 92612, and have appointed Steven D. Pratt, Kevin Thomas and Seth L. Smythe, and each of them, as the Attorneys in Fact for the Selling Stockholders. T&J Anderson Family Investments, LLC is represented by Stamper Rubens Law Firm PS, 720 West Boone Ave., Suite 200, Spokane, WA 99201.

SCHEDULE IV

SIGNIFICANT SUBSIDIARIES

Name		Jurisdiction of incorporation
ESCO Australia Holdings Pty Ltd.		Australia
ESCO Bucyrus Blades Canada Partnership		Canada
ESCO Limited		Canada
ESCO Canada Finance Company, Inc.		Canada
ESCO TT Syracuse		New York, USA

SCHEDULE V

STOCKHOLDERS TO BE SUBJECT TO LOCK-UP AGREEMENTS

1. Lucy Christenson Warren Trust

2. Swigert 2000 Trust

3. Henry T Swigert Declaration of Trust UTA dtd 12/12/08 as amended

4. Henry T Swigert Trust U/A dtd 6/23/09 as amended & restated

5. Peter F. Adams Family Trust

6. F. Patrick Fonner and B. Lynne Fonner Trust UA dtd 8/6/2009

7. Francis Jungers Trust

8. John W. Wood, Jr. Revocable Trust of 2008 dtd 10-1008 as amended

ANNEX III

FORM OF LOCK-UP AGREEMENT

Goldman, Sachs & Co.

Morgan Stanley & Co. Incorporated

c/o Goldman, Sachs & Co.

200 West Street

New York, New York 10282-2198

c/o Morgan Stanley & Co. Incorporated

1585 Broadway

New York, New York 10036-8293

Re: ESCO CORPORATION - Lock-Up Agreement

Ladies and Gentlemen:

The undersigned understands that you, as representatives (the “Representatives”), propose to enter into an Underwriting Agreement on behalf of the several Underwriters named in Schedule I to such agreement (collectively, the “Underwriters”), with ESCO Corporation, an Oregon corporation (the “Company”), providing for a public offering of a new class of common stock (the “Public Common Stock”) of the Company (the “Shares”) pursuant to a Registration Statement on Form S-1 to be filed with the Securities and Exchange Commission (the “SEC”).

In consideration of the agreement by the Underwriters to offer and sell the Shares, and of other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the undersigned agrees that, during the period specified in the following paragraph (the “Lock-Up Period”), the undersigned will not offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose of any shares of Public Common Stock of the Company, or any options or warrants to purchase any shares of Public Common Stock of the Company, or any securities convertible into, exchangeable for or that represent the right to receive shares of Public Common Stock of the Company (including any shares of Class A common stock and Class B common stock), whether now owned or hereinafter acquired, owned directly by the undersigned (including holding as a custodian) or with respect to which the undersigned has beneficial ownership within the rules and regulations of the SEC (collectively the “Undersigned’s Shares”). The foregoing restriction is expressly agreed to preclude the undersigned from engaging in any hedging or other transaction which is designed to or which reasonably could be expected to lead to or result in a sale or disposition of the Undersigned’s Shares even if such Shares would be disposed of by someone other than the undersigned. Such prohibited hedging or other transactions would include without limitation any short sale or any purchase, sale or grant of any right (including without limitation any put or call option) with respect to any of the Undersigned’s Shares or with respect to any security that includes, relates to, or derives any significant part of its value from such Shares.

The initial Lock-Up Period will commence on the date of this Lock-Up Agreement and continue for 180 days after the public offering date set forth on the final prospectus used to sell the Shares (the “Public Offering Date”) pursuant to the Underwriting Agreement; provided, however, that if (1) during the last 17 days of the initial Lock-Up Period, the Company releases earnings results or announces material news or a material event or (2) prior to the expiration of the initial Lock-Up Period, the Company announces that it will release earnings

results during the 15-day period following the last day of the initial Lock-Up Period, then in each case the Lock-Up Period will be automatically extended until the expiration of the 18-day period beginning on the date of release of the earnings results or the announcement of the material news or material event, as applicable, unless each of the Representatives waives, in writing, such extension.

The undersigned hereby acknowledges that the Underwriting Agreement will provide that the Company will give written notice of any event that would result in an extension of the Lock-Up Period pursuant to the previous paragraph to the undersigned (in accordance with Section 14 of the Underwriting Agreement) and agrees that any such notice properly delivered will be deemed to have been given to, and received by, the undersigned. The undersigned hereby further agrees that, prior to engaging in any transaction or taking any other action that is subject to the terms of this Lock-Up Agreement during the period from the date of this Lock-Up Agreement to and including the 34th day following the expiration of the initial Lock-Up Period, it will give notice thereof to the Company and will not consummate such transaction or take any such action unless it has received written confirmation from the Company that the Lock-Up Period (as such may have been extended pursuant to the previous paragraph) has expired.

Notwithstanding the foregoing, the undersigned may transfer the Undersigned’s Shares (i) as a bona fide gift or gifts, provided that the donee or donees thereof agree to be bound in writing by the restrictions set forth herein, (ii) to any trust for the direct or indirect benefit of the undersigned or the immediate family of the undersigned, provided that the trustee of the trust agrees to be bound in writing by the restrictions set forth herein, and provided further that any such transfer shall not involve a disposition for value, (iii) with the prior written consent of each of the Representatives on behalf of the Underwriters, or (iv) in connection with a sale to the Underwriters pursuant to the Underwriting Agreement. For purposes of this Lock-Up Agreement, “immediate family” shall mean any relationship by blood, marriage or adoption, not more remote than first cousin. The undersigned now has, and, except as contemplated by clause (i), (ii), or (iii) above, for the duration of this Lock-Up Agreement will have, good and marketable title to the Undersigned’s Shares, free and clear of all liens, encumbrances, and claims whatsoever. The undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar against the transfer of the Undersigned’s Shares except in compliance with the foregoing restrictions.

This Lock-Up Agreement shall automatically terminate on the date the Company provides written notice to the Representatives that the Company has determined not to proceed with the proposed public offering and is terminating the Lock-Up Agreement on behalf of the undersigned, provided that the Company and the Representatives shall not have executed the Underwriting Agreement on or before that date.

The undersigned understands that the Company and the Underwriters are relying upon this Lock-Up Agreement in proceeding toward consummation of the offering. The undersigned further understands that this Lock-Up Agreement is irrevocable and shall be binding upon the undersigned’s heirs, legal representatives, successors, and assigns.

	Very truly yours,


	Exact Name of Shareholder


	Authorized Signature


	Title


	Date

ESCO Corp S-1/A