NOTE PURCHASE AGREEMENT

Exhibit 10(x)

SIGMA–ALDRICH CORPORATION

$100,000,000

7.687% Senior Notes due September 12, 2010

NOTE PURCHASE AGREEMENT

Dated: September 12, 2000

Exhibit 10(x) (continued)

T ABLE OF C ONTENTS

i

Exhibit 10(x) (continued)

ii

Exhibit 10(x) (continued)

iii

Exhibit 10(x) (continued)

SIGMA–ALDRICH CORPORATION

3050 SPRUCE STREET

ST. LOUIS, MISSOURI 63103

7.687% S ENIOR N OTES due September 12, 2010

September 12, 2000

T O EACH OF THE P URCHASERS LISTED IN

     THE ATTACHED S CHEDULE  A:

Ladies and Gentlemen:

Sigma–Aldrich Corporation, a Delaware corporation, together with its successors and assigns (the “Company” ), agrees with you as follows:

S ECTION  1 . A UTHORIZATION OF N OTES .

The Company has authorized the issue and sale of $100,000,000 aggregate principal amount of its 7.687% Senior Notes due September 12, 2010 (the “Notes” , such term to include any such notes issued in substitution therefor pursuant to Section 13 of this Agreement or the Other Agreements (as hereinafter defined)). The Notes shall be substantially in the form set out in Exhibit 1, with such changes therefrom, if any, as may be approved by you and the Company. Certain capitalized terms used in this Agreement are defined in Schedule B; references to a “Schedule” or an “Exhibit” are, unless otherwise specified, to a Schedule or an Exhibit attached to this Agreement.

S ECTION  2. S ALE AND P URCHASE OF N OTES .

Subject to the terms and conditions of this Agreement, the Company will issue and sell to you and you will purchase from the Company, at the Closing provided for in Section 3, Notes in the principal amount specified opposite your name in Schedule A at the purchase price of 100% of the principal amount thereof.

Contemporaneously with entering into this Agreement, the Company is entering into separate Note Purchase Agreements (the “Other Agreement s ” ) identical with this Agreement with each of the other purchasers named in Schedule A (the “Other Purchasers” ), providing for the sale at such Closing to each of the Other Purchasers of Notes in the principal amount specified opposite its name in Schedule A. Your obligation hereunder and the obligations of the Other Purchasers under the Other Agreements are several and not joint obligations and you shall have no obligation under any Other Agreement and no liability to any Person for the performance or nonperformance by any Other Purchaser thereunder.

Exhibit 10(x) (continued)

S ECTION  3. C LOSING .

The sale and purchase of the Notes to be purchased by you shall occur at the offices of Bryan Cave, LLP, 211 North Broadway, One Metropolitan Square, Suite 3600, St. Louis, Missouri 63102 at 10:00 a.m. CDT, at a closing (the “Closing”) on September 12, 2000 or on such other Business Day thereafter on or prior to October 1, 2000 as may be agreed upon by the Company and you. At the Closing the Company will deliver to you the Notes to be purchased by you in the form of a single Note dated the date of the Closing and registered in your name (or in the name of your nominee), against delivery by you to the Company or its order of immediately available funds in the amount of the purchase price therefor by wire transfer of immediately available funds for the account of the Company to: Firstar Bank, N.A., ABA# 081-000-210, Account #1005017999, Account Name: Sigma-Aldrich Corporation. If at the Closing the Company shall fail to tender such Notes to you as provided above in this Section 3, or any of the conditions specified in Section 4 shall not have been fulfilled to your satisfaction, you shall, at your election, be relieved of all further obligations under this Agreement, without thereby waiving any rights you may have by reason of such failure or such nonfulfillment.

S ECTION  4. C ONDITIONS TO C LOSING .

Your obligation to purchase and pay for the Notes to be sold to you at the Closing is subject to the fulfillment to your satisfaction, prior to or at the Closing, of the following conditions:

Section 4.1. Representations and Warranties . The representations and warranties of the Company in this Agreement shall be correct when made and at the time of the Closing.

Section 4.2. Performance; No Default . The Company shall have performed and complied with all agreements and conditions contained in this Agreement required to be performed or complied with by it prior to or at the Closing and after giving effect to the issue and sale of the Notes (and the application of the proceeds thereof as contemplated by Schedule 5.14) no Default or Event of Default shall have occurred and be continuing.

Section 4.3 . Compliance Certificates .

(a) Officer’s Certificate . The Company shall have delivered to you an Officer’s Certificate, dated the date of the Closing, certifying that the conditions specified in Sections 4.1, 4.2 and 4.9 have been fulfilled.

(b) Secretary’s Certificate . The Company shall have delivered to you a certificate certifying as to the resolutions attached thereto and other corporate proceedings relating to the authorization, execution and delivery of the Notes and the Agreements.

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Exhibit 10(x) (continued)

Section 4.4. Opinions of Counsel . You shall have received an opinion in form and substance satisfactory to you, dated the date of the Closing from Bryan Cave, counsel for the Company, covering the matters set forth in Exhibit 4.4 and covering such other matters incident to the transactions contemplated hereby as you or your counsel may reasonably request (and the Company hereby instructs its counsel to deliver such opinion to you).

Section 4.5. Purchase Permitted by Applicable Law, etc . On the date of the Closing your purchase of Notes shall (i) be permitted by the laws and regulations of each jurisdiction to which you are subject, without recourse to provisions (such as Section 1405(a)(8) of the New York Insurance Law) permitting limited investments by insurance companies without restriction as to the character of the particular investment, (ii) not violate any applicable law or regulation (including, without limitation, Regulation G, T or X of the Board of Governors of the Federal Reserve System) and (iii) not subject you to any tax, penalty or liability under or pursuant to any applicable law or regulation, which law or regulation was not in effect on the date hereof. If requested by you, you shall have received an Officer’s Certificate certifying as to such matters of fact as you may reasonably specify to enable you to determine whether such purchase is so permitted.

Section 4.6. Sale of Other Notes. Contemporaneously with the Closing the Company shall sell to the Other Purchasers and the Other Purchasers shall purchase the Notes to be purchased by them at the Closing as specified in Schedule A.

Section 4.7. Intentionally deleted.

Section 4.8. Private Placement Number. A Private Placement Number issued by Standard & Poor’s CUSIP Service Bureau (in cooperation with the Securities Valuation Office of the National Association of Insurance Commissioners) shall have been requested by and obtained for the Notes by the Purchaser.

Section 4.9. Changes in Corporate Structure. Except as specified in Schedule 4.9, the Company shall not have changed its jurisdiction of incorporation or been a party to any merger or consolidation and shall not have succeeded to all or any substantial part of the liabilities of any other entity, at any time following the date of the most recent financial statements referred to in Schedule 5.5.

Section 4.10. Proceedings and Documents. All corporate and other proceedings in connection with the transactions contemplated by this Agreement and all documents and instruments incident to such transactions shall be satisfactory to you and your counsel, and you and your counsel shall have received all such counterpart originals or certified or other copies of such documents as you or they may reasonably request.

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Exhibit 10(x) (continued)

S ECTION  5. R EPRESENTATIONS AND W ARRANTIES OF THE C OMPANY .

The Company represents and warrants to you as of the Date of the Closing that:

Section 5.1. Organization; Power and Authority. The Company is a corporation duly organized, validly existing and in good standing under the laws of its jurisdiction of incorporation, and is duly qualified as a foreign corporation and is in good standing in each jurisdiction in which such qualification is required by law, other than those jurisdictions as to which the failure to be so qualified or in good standing would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. The Company has the corporate power and authority to own or hold under lease the properties it purports to own or hold under lease, to transact the business it transacts and proposes to transact, to execute and deliver this Agreement and the Other Agreements and the Notes and to perform the provisions hereof and thereof.

Section 5.2. Authorization, etc. This Agreement and the Other Agreements and the Notes have been duly authorized by all necessary corporate action on the part of the Company, and this Agreement constitutes, and upon execution and delivery thereof each Note will constitute, a legal, valid and binding obligation of the Company enforceable against the Company in accordance with its terms, except as such enforceability may be limited by (i) applicable bankruptcy, insolvency, reorganization, moratorium or other similar laws affecting the enforcement of creditors’ rights generally and (ii) general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law).

Section 5.3. Disclosure. The Company has executed and delivered to you that certain Commitment dated August 9, 2000 which contained a Term Sheet (the “Term Sheet”) summarizing the main terms relating to the transactions completed herein. Except as disclosed in Schedule 5.3, this Agreement, the Term Sheet, the documents, certificates or other writings identified in Schedule 5.3 and the financial statements listed in Schedule 5.5, taken as a whole, do not contain any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein not misleading in light of the circumstances under which they were made. Except as disclosed in the Term Sheet or as expressly described in Schedule 5.3, or in one of the documents, certificates or other writings identified therein, or in the financial statements listed in Schedule 5.5, since December 31, 1999 there has been no change in the financial condition, operations, business or properties of the Company or any of its Subsidiaries except changes that individually or in the aggregate would not reasonably be expected to have a Material Adverse Effect.

Section 5.4. Organization and Ownership of Shares of Subsidiaries.

(a) Schedule 5.4 is (except as noted therein) a complete and correct list of the Company’s Subsidiaries, showing, as to each Subsidiary, the correct name thereof, the jurisdiction of its organization, and the percentage of shares of each class of its capital stock or similar equity interests outstanding owned by the Company and each other Subsidiary.

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Exhibit 10(x) (continued)

(b) All of the outstanding shares of capital stock or similar equity interests of each Subsidiary shown in Schedule 5.4 as being owned by the Company and its Subsidiaries have been validly issued, are fully paid and nonassessable and are owned by the Company or another Subsidiary free and clear of any Lien (except as otherwise disclosed in Schedule 5.4).

(c) Each Subsidiary identified in Schedule 5.4 is a corporation or other legal entity duly organized, validly existing and in good standing under the laws of its jurisdiction of organization, and is duly qualified as a foreign corporation or other legal entity and is in good standing in each jurisdiction in which such qualification is required by law, other than those jurisdictions as to which the failure to be so qualified or in good standing would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. Each such Subsidiary has the corporate or other power and authority to own or hold under lease the properties it purports to own or hold under lease and to transact the business it transacts and proposes to transact.

Section 5.5. Financial Statement s . The Company has delivered to each Purchaser copies of the financial statements of the Company and its Subsidiaries listed on Schedule 5.5. All of said financial statements (including in each case the related schedules and notes) fairly present in all material respects the consolidated financial position of the Company and its Subsidiaries as of the respective dates specified in such Schedule and the consolidated results of their operations and cash flows for the respective periods so specified and have been prepared in accordance with GAAP consistently applied throughout the periods involved except as set forth in the notes.

Section 5.6. Compliance with Laws, Other Instruments, etc . The execution, delivery and performance by the Company of this Agreement and the Notes will not (x) contravene, result in any breach of, or constitute a default under, or result in the creation of any Lien in respect of any property of the Company or any Subsidiary under any Material: (i) indenture; (ii) mortgage; (iii) deed of trust; (iv) loan; (v) purchase or credit agreement; (vi) lease; (vii) corporate charter or by-laws; or (viii) any other agreement or instrument to which the Company or any Subsidiary is bound or by which the Company or any Subsidiary or any of their respective properties may be bound or affected, (y) conflict with or result in a breach of any of the terms, conditions or provisions of any order, judgment, decree, or ruling of any court, arbitrator or Governmental Authority applicable to the Company or any Subsidiary or (z) violate any provision of any statute or other rule or regulation of any Governmental Authority applicable to the Company or any Subsidiary.

Section 5.7. Governmental Authorizations, etc . No consent, approval or authorization of, or registration, filing or declaration with, any Governmental Authority is required in connection with the execution, delivery or performance by the Company of this Agreement or the Notes.

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Exhibit 10(x) (continued)

Section 5.8. Litigation; Observance of Statutes and Orders . (a)  Except as disclosed in Schedule 5.8, there are no actions, suits or proceedings pending or, to the knowledge of the Company, threatened against or affecting the Company or any Subsidiary or any property of the Company or any Subsidiary in any court or before any arbitrator of any kind or before or by any Governmental Authority that, individually or in the aggregate, would reasonably be expected to have a Material Adverse Effect.

(b) Neither the Company nor any Subsidiary is in default under any order, judgment, decree or ruling of any court, arbitrator or Governmental Authority or is in violation of any applicable law, ordinance, rule or regulation (including without limitation Environmental Laws) of any Governmental Authority, which default or violation, individually or in the aggregate, would reasonably be expected to have a Material Adverse Effect.

Section 5.9. Taxes . As of September 15, 1999, the Company and its Subsidiaries have filed all income tax returns that are required to have been filed in any jurisdiction, and have paid all taxes shown to be due and payable on such returns and all other taxes and assessments payable by them, to the extent such taxes and assessments have become due and payable and before they have become delinquent, except for any taxes and assessments (i) the amount of which is not individually or in the aggregate Material or (ii) the amount, applicability or validity of which is currently being contested in good faith by appropriate proceedings and with respect to which the Company or a Subsidiary, as the case may be, has established adequate reserves in accordance with GAAP. The United States Federal income tax liabilities of the Company and its Subsidiaries have been determined, examined and accepted by the Internal Revenue Service and paid for all fiscal years up to and including the fiscal year ended December 31, 1996.

Section 5.10. Title to Property; Leases . The Company and its Subsidiaries have good and sufficient title to their respective Material properties, including all such properties reflected in the most recent audited balance sheet referred to in Section 5.5 or purported to have been acquired by the Company or any Subsidiary after said date (except as sold or otherwise disposed of in the ordinary course of business), in each case free and clear of Liens prohibited by this Agreement, except for those defects in title and Liens that, individually or in the aggregate, would not have a Material Adverse Effect. All Material leases are valid and subsisting and are in full force and effect in all material respects.

Section 5.11. Licenses, Permits, etc . Except as disclosed in Schedule 5.11, the Company and its Subsidiaries own or possess all licenses, permits, franchises, authorizations, patents, copyrights, service marks, trademarks and trade names, or rights thereto, that are Material, without known conflict with the rights of others, except for those conflicts that, individually or in the aggregate, would not have a Material Adverse Effect.

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Exhibit 10(x) (continued)

Section 5.12. Compliance with ERISA . To the best of the Company’s knowledge:

(a) the Company and each ERISA Affiliate have operated and administered each Plan in compliance with all applicable laws except for such instances of noncompliance as have not resulted in and could not reasonably be expected to result in a Material Adverse Effect. Neither the Company nor any ERISA Affiliate has incurred any liability pursuant to Title I or IV of ERISA or the penalty or excise tax provisions of the Code relating to employee benefit plans (as defined in Section 3 of ERISA), and no event, transaction or condition has occurred or exists that would reasonably be expected to result in the incurrence of any such liability by the Company or any ERISA Affiliate, or in the imposition of any Lien on any of the rights, properties or assets of the Company or any ERISA Affiliate, in either case pursuant to Title I or IV of ERISA or to such penalty or excise tax provisions or to Section 401(a)(29) or 412 of the Code, other than such liabilities or Liens as would not be individually or in the aggregate Material.

(b) The present value of the aggregate benefit liabilities under each of the Plans (other than Multi-employer Plans), determined as of the end of such Plan’s most recently ended plan year on the basis of the actuarial assumptions specified for funding purposes in such Plan’s most recent actuarial valuation report, did not exceed the aggregate current value of the assets of such Plan allocable to such benefit liabilities. The term “benefit liabilities” has the meaning specified in Section 4001 of ERISA and the terms “current value” and “present value” have the meaning specified in Section 3 of ERISA.

(c) The Company and its ERISA Affiliates have not incurred withdrawal liabilities (and are not subject to contingent withdrawal liabilities) under section 4201 or 4204 of ERISA in respect of Multi-employer Plans that individually or in the aggregate are Material.

(d) The expected post-retirement benefit obligation (determined as of the last day of the Company’s most recently ended fiscal year in accordance with Financial Accounting Standards Board Statement No. 106, without regard to liabilities attributable to continuation coverage mandated by section 4980B of the Code) of the Company and its Subsidiaries is approximately $42,600,000 as of December 31, 1999.

(e) The execution and delivery of this Agreement and the issuance and sale of the Notes hereunder will not involve any transaction that is subject to the prohibitions of section 406 of ERISA or in connection with which a tax could be imposed pursuant to section 4975(c)(1)(A)-(D) of the Code. The representation by the Company in the first sentence of this Section 5.12(e) is made in reliance upon and subject to (i) the accuracy of your representation in Section 6.2 as to the sources of the funds to be used to pay the purchase price of the Notes to be purchased by you and (ii) the assumption, made solely for the purpose of making such representation, that Department of Labor Interpretive Bulletin 75-2 with respect to prohibited transactions remains valid in the circumstances of the transactions contemplated herein.

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Exhibit 10(x) (continued)

Section 5.13. Private Offering by the Company . Neither the Company nor anyone acting on its behalf has offered the Notes or any similar securities for sale to, or solicited any offer to buy any of the same from, or otherwise approached or negotiated in respect thereof with, any person other than you, who has been offered the Notes at a private sale for investment. Neither the Company nor anyone acting on its behalf has taken, or will take, any action that would subject the issuance or sale of the Notes to the registration requirements of Section 5 of the Securities Act.

Section 5.14. Use of Proceeds; Margin Regulation s . The Company will apply the proceeds of the sale of the Notes as set forth in Schedule 5.14. No part of the proceeds from the sale of the Notes hereunder will be used, directly or indirectly, for the purpose of buying or carrying any margin stock within the meaning of Regulation U of the Board of Governors of the Federal Reserve System (12 CFR 221) other than the capital stock of the Company which will be immediately retired or held by the Company as treasury stock, or for the purpose of buying or carrying or trading in any securities under such circumstances as to involve the Company in a violation of Regulation U of said Board (12 CFR 224) or to involve any broker or dealer in a violation of Regulation T of said Board (12 CFR 220). Margin stock does not constitute more than 0% of the value of the consolidated assets of the Company and its Subsidiaries and the Company does not have any present intention that margin stock will constitute more than 0% of the value of such assets. As used in this Section, the terms “margin stock” and “ purpose of buying or carrying” shall have the meanings assigned to them in said Regulation U.

Section 5.15. Existing Indebtedne ss . Except as described therein, Schedule 5.15 sets forth a complete and correct list of all outstanding Indebtedness of the Company and its Subsidiaries as of July 31, 2000, since which date there has been no Material change in the amounts, interest rates, sinking funds, installment payments or maturities of the Indebtedness of the Company or its Subsidiaries. Neither the Company nor any Subsidiary is in default and no waiver of default is currently in effect, in the payment of any principal or interest on any Indebtedness of the Company or such Subsidiary and no event or condition exists with respect to any Indebtedness of the Company or any Subsidiary the outstanding principal amount of which exceeds $10,000,000 that would permit (or that with notice or the lapse of time, or both, would permit) one or more Persons to cause such Indebtedness to become due and payable before its stated maturity or before its regularly scheduled dates of payment.

Section 5.16. Foreign Assets Control Regulations, e tc . Neither the sale of the Notes by the Company hereunder nor its use of the proceeds thereof will violate the Trading with the Enemy Act, as amended, or any of the foreign assets control regulations of the United States Treasury Department (31 CFR, Subtitle B, Chapter V, as amended) or any enabling legislation or executive order relating thereto.

Section 5.17. Status under Certain Statut es . Neither the Company nor any Subsidiary is subject to regulation under the Investment Company Act of 1940, as amended, the Public Utility Holding Company Act of 1935, as amended, the Interstate Commerce Act, as amended, or the Federal Power Act, as amended.

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Exhibit 10(x) (continued)

Section 5.18. Environmental Matters. Neither the Company nor any Subsidiary has knowledge of any claim or has received any notice of any claim, and no proceeding has been instituted raising any claim against the Company or any of its Subsidiaries or any of their respective real properties now or formerly owned, leased or operated by any of them or other assets, alleging any damage to the environment or violation of any Environmental Laws, except, in each case, such as could not reasonably be expected to result in a Material Adverse Effect. Except as otherwise disclosed to you in writing:

(a) neither the Company nor any Subsidiary has knowledge of any facts which would give rise to any claim, public or private, of violation of Environmental Laws or damage to the environment emanating from, occurring on or in any way related to real properties now or formerly owned, leased or operated by any of them or to other assets or their use, except, in each case, such as could not reasonably be expected to result in a Material Adverse Effect;

(b) neither the Company nor any of its Subsidiaries has stored any Hazardous Materials on real properties now or formerly owned, leased or operated by any of them or disposed of any Hazardous Materials in a manner contrary to any Environmental Laws in each case in any manner that could reasonably be expected to result in a Material Adverse Effect; and

(c) all buildings on all real properties now owned, leased or operated by the Company or any of its Subsidiaries are in compliance with applicable Environmental Laws, except where failure to comply could not reasonably be expected to result in a Material Adverse Effect.

S ECTION  6. R EPRESENTATIONS OF THE P URCHASER .

Section 6.1. Purchase for Investment . You represent that you are purchasing the Notes for your own account or for one or more separate accounts maintained by you or for the account of one or more pension or trust funds and not with a view to the distribution thereof, provided that the disposition of your or their property shall at all times be within your or their control. You understand that the Notes have not been registered under the Securities Act and may be resold only if registered pursuant to the provisions of the Securities Act or if an exemption from registration is available, except under circumstances where neither such registration nor such an exemption is required by law, and that the Company is not required to register the Notes.

Section 6.2. Source of Funds . You represent that at least one of the following statements is an accurate representation as to each source of funds (a “Source” ) to be used by you to pay the purchase price of the Notes to be purchased by you hereunder:

(a) if you are an insurance company, the Source does not include assets allocated to any separate account maintained by you in which any employee benefit plan (or its related trust) has any interest, other than a separate account that is maintained

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Exhibit 10(x) (continued)

solely in connection with your fixed contractual obligations under which the amounts payable, or credited, to such plan and to any participant or beneficiary of such plan (including any annuitant) are not affected in any manner by the investment performance of the separate account; or

(b) the Source is either (i) an insurance company pooled separate account, within the meaning of Prohibited Transaction Exemption ( “PTE” ) 90-1 (issued January 29, 1990), or (ii) a bank collective investment fund, within the meaning of the PTE 91-38 (issued July 12, 1991) and, except as you have disclosed to the Company in writing pursuant to this paragraph (b), no employee benefit plan or group of plans maintained by the same employer or employee organization beneficially owns more than 10% of all assets allocated to such pooled separate account or collective investment fund; or

(c) the Source constitutes assets of an “investment fund” (within the meaning of Part V of the QPAM Exemption) managed by a “qualified professional asset manager” or “QPAM” (within the meaning of Part V of the QPAM Exemption), no employee benefit plan’s assets that are included in such investment fund, when combined with the assets of all other employee benefit plans established or maintained by the same employer or by an affiliate (within the meaning of Section V(c)(1) of the QPAM Exemption) of such employer or by the same employee organization and managed by such QPAM, exceed 20% of the total client assets managed by such QPAM, the conditions of Part I(c) and (g) of the QPAM Exemption are satisfied, neither the QPAM nor a person controlling or controlled by the QPAM (applying the definition of “control” in Section V(e) of the QPAM Exemption) owns a 5% or more interest in the Company and (i) the identity of such QPAM and (ii) the names of all employee benefit plans whose assets are included in such investment fund have been disclosed to the Company in writing pursuant to this paragraph (c); or

(d) the Source is a governmental plan; or

(e) the Source is one or more employee benefit plans, or a separate account or trust fund comprised of one or more employee benefit plans, each of which has been identified to the Company in writing pursuant to this paragraph (e); or

(f) the Source does not include assets of any employee benefit plan, other than a plan exempt from the coverage of ERISA; or

(g) the Source is an “insurance company general account” within the meaning of PTE 95-60 (issued July 12, 1995) and there is no employee benefit plan, treating as a single plan, all plans maintained by the same employer or employee organization, with respect to which the amount of the general account reserves and liabilities for all contracts held by or on behalf of such plan, exceed 10% of the total reserves and liabilities of such general account (exclusive of separate account liabilities) plus surplus, as set forth in the NAIC Annual Statement filed with your state of domicile.

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Exhibit 10(x) (continued)

As used in this Section 6.2, the terms “employee benefit plan”, “governmental plan”, “party in interest” and “separate account” shall have the respective meanings assigned to such terms in Section 3 of ERISA.

S ECTION  7. I NFORMATION AS TO C OMPANY .

Section 7.1. Financial and Business Information . The Company shall deliver to each holder of Notes that is an Institutional Investor:

(a) Quarterly Statements. Within 60 days after the end of each quarterly fiscal period in each fiscal year of the Company (other than the last quarterly fiscal period of each such fiscal year), duplicate copies of:

(i) a consolidated balance sheet of the Company and its Subsidiaries as at the end of such quarter, and

(ii) consolidated statements of income, changes in shareholders’ equity and cash flows of the Company and its Subsidiaries, for such quarter and (in the case of the second and third quarters) for the portion of the fiscal year ending with such quarter,

setting forth in each case in comparative form the figures for the corresponding periods in the previous fiscal year, all in reasonable detail, prepared in accordance with GAAP applicable to quarterly financial statements generally, and certified by a Senior Financial Officer as fairly presenting, in all material respects, the financial position of the companies being reported on and their results of operations and cash flows, subject to changes resulting from year-end adjustments, provided that delivery within the time period specified above of copies of the Company’s Quarterly Report on Form 10-Q prepared in compliance with the requirements therefor and filed with the Securities and Exchange Commission shall be deemed to satisfy the requirements of this Section 7.1(a);

(b) Annual Statements. Within 105 days after the end of each fiscal year of the Company, duplicate copies of,

(i) a consolidated balance sheet of the Company and its Subsidiaries, as at the end of such year, and

(ii) consolidated statements of income, changes in shareholders’ equity and cash flows of the Company and its Subsidiaries, for such year, setting forth in each case in comparative form the figures for the previous fiscal year, all in reasonable detail, prepared in accordance with GAAP, and accompanied by an opinion thereon of independent certified public accountants of recognized national standing, which opinion shall state that such financial statements present fairly, in all material respects, the financial position of the companies being reported upon and their results of operations and cash flows and have been prepared in conformity with GAAP, and that the examination of such accountants in connection with such financial statements has been

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Exhibit 10(x) (continued)

made in accordance with generally accepted auditing standards, and that such audit provides a reasonable basis for such opinion in the circumstances, provided that the delivery within the time period specified above of the Company’s Annual Report on Form 10-K for such fiscal year (together with the Company’s annual report to shareholders, if any, prepared pursuant to Rule 14a-3 under the Exchange Act) prepared in accordance with the requirements therefor and filed with the Securities and Exchange Commission shall be deemed to satisfy the requirements of this Section 7.1(b);

(c) SEC and Other Reports. Promptly upon their becoming available, one copy of (i) each financial statement, report, notice or proxy statement sent by the Company or any Subsidiary to public securities holders generally, and (ii) each regular or periodic report, each registration statement that shall have become effective (without exhibits except as expressly requested by such holder), and each final prospectus and all amendments thereto filed by the Company or any Subsidiary with the Securities and Exchange Commission;

(d) Notice of Default or Event of Default. Promptly, and in any event within five days after a Responsible Officer becoming aware of the existence of any Default or Event of Default, a written notice specifying the nature and period of existence thereof and what action the Company is taking or proposes to take with respect thereto;

(e) ERISA Matters. Promptly, and in any event within five days after a Responsible Officer becoming aware of any of the following, a written notice setting forth the nature thereof and the action, if any, that the Company or an ERISA Affiliate proposes to take with respect thereto:

(i) with respect to any Plan, any reportable event, as defined in section 4043(b) of ERISA and the regulations thereunder, for which notice thereof has not been waived pursuant to such regulations as in effect on the date hereof; or

(ii) the taking by the PBGC of steps to institute, or the threatening by the PBGC of the institution of, proceedings under section 4042 of ERISA for the termination of, or the appointment of a trustee to administer, any Plan, or the receipt by the Company or any ERISA Affiliate of a notice from a Multiemployer Plan that such action has been taken by the PBGC with respect to such Multiemployer Plan; or

(iii) any event, transaction or condition that could result in the incurrence of any liability by the Company or any ERISA Affiliate pursuant to Title I or IV of ERISA or the penalty or excise tax provisions of the Code relating to employee benefit plans, or in the imposition of any Lien on any of the rights, properties or assets of the Company or any ERISA Affiliate pursuant to Title I or IV of ERISA or such penalty or excise tax provisions, if such liability or Lien, taken together with any other such liabilities or Liens then existing, would reasonably be expected to have a Material Adverse Effect;

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Exhibit 10(x) (continued)

(f) Requested Information. With reasonable promptness, such other data and information relating to the business, operations, affairs, financial condition, assets or properties of the Company or any of its Subsidiaries or relating to the ability of the Company to perform its obligations hereunder and under the Notes as from time to time may be reasonably requested by any such holder of Notes;

(g) Notices from Governmental Authority. Promptly, and in any event within 30 days of receipt thereof, copies of any notice to the Company or any Subsidiary from any Federal or state Governmental Authority relating to any order, ruling, statute or other law or regulation that could reasonably be expected to have a Material Adverse Effect; and

(h) Actions, Proceedings. Promptly after a Responsible Officer becomes aware of the commencement thereof, notice of any action or proceeding relating to the Company or any Subsidiary in any court or before any Governmental Authority or arbitration board or tribunal as to which there is a reasonable possibility of an adverse determination and that, if adversely determined, could reasonably be expected to have a Material Adverse Effect.

Section 7.2. Officer’s Certificat e . Each set of financial statements delivered to a holder of Notes pursuant to Section 7.1(a) or Section 7.1(b) hereof shall be accompanied by a certificate of a Senior Financial Officer setting forth:

(a) Covenant Compliance. The information (including detailed calculations) required in order to establish whether the Company was in compliance with the requirements of Section 10 hereof, inclusive, during the quarterly or annual period covered by the statements then being furnished (including with respect to each such Section, where applicable, the calculations of the maximum or minimum amount, ratio or percentage, as the case may be, permissible under the terms of such Sections, and the calculation of the amount, ratio or percentage then in existence); and

(b) Event of Default. A statement that such officer has reviewed the relevant terms hereof and has made, or caused to be made, under his or her supervision, a review of the transactions and conditions of the Company and its Subsidiaries from the beginning of the quarterly or annual period covered by the statements then being furnished to the date of the certificate and that such review shall not have disclosed the existence during such period of any condition or event that constitutes a Default or an Event of Default or, if any such condition or event existed or exists (including, without limitation, any such event or condition resulting from the failure of the Company or any Subsidiary to comply with any Environmental Law), specifying the nature and period of existence thereof and what action the Company shall have taken or proposes to take with respect thereto.

13

Exhibit 10(x) (continued)

Section 7.3. Inspection . The Company shall permit the representatives of each holder of Notes that is an Institutional Investor:

(a) No Default . If no Default or Event of Default then exists, at the expense of such holder and upon reasonable prior notice to the Company, to visit the principal executive office of the Company, to discuss the affairs, finances and accounts of the Company and its Subsidiaries with the Company’s officers, and, with the consent of the Company (which consent will not be unreasonably withheld) to visit the other offices and properties of the Company and each Subsidiary, all at such reasonable times and as often as may be reasonably requested in writing; and

(b) Default. If a Default or Event of Default then exists, at the expense of the Company to visit and inspect any of the offices or properties of the Company or any Subsidiary, to examine all their respective books of account, records, reports and other papers, to make copies and extracts therefrom, and to discuss their respective affairs, finances and accounts with their respective officers and independent public accountants (and by this provision the Company authorizes said accountants to discuss the affairs, finances and accounts of the Company and its Subsidiaries), all at such times and as often as may be requested.

S ECTION  8. P REPAYMENT OF THE N OTES .

Section 8.1 . Intentionally deleted.

Section 8.2 . Optional Prepayments with Make-Whole Amount . The Company may, at its option, upon notice as provided below, prepay at any time all, or from time to time any part of, the Notes, in a principal amount of not less than $10,000,000 in the case of a partial prepayment, at 100% of the principal amount so prepaid, plus accrued interest plus the Make-Whole Amount determined for the prepayment date with respect to such principal amount. The Company will give each holder of Notes written notice of each optional prepayment under this Section 8.2 not less than 30 days and not more than 60 days prior to the date fixed for such prepayment. Each such notice shall specify such date, the aggregate principal amount of the Notes to be prepaid on such date, the principal amount of each Note held by such holder to be prepaid (determined in accordance with Section 8.3), and the interest to be paid on the prepayment date with respect to such principal amount being prepaid, and shall be accompanied by a certificate of a Senior Financial Officer as to the estimated Make-Whole Amount due in connection with such prepayment (calculated as if the date of such notice were the date of the prepayment), setting forth the details of such computation. Two Business Days prior to such prepayment, the Company shall deliver to each holder of Notes a certificate of a Senior Financial Officer specifying the calculation of such Make-Whole Amount as of the specified prepayment date.

Section 8.3. Allocation of Partial Prepayment s . In the case of each partial prepayment of the Notes, the principal amount of the Notes to be prepaid shall be allocated among all of the Notes at the time outstanding in proportion, as nearly as practicable, to the respective unpaid principal amounts thereof not theretofore called for prepayment.

14

Exhibit 10(x) (continued)

Section 8.4. Maturity; Surrender, etc . In the case of each prepayment of Notes pursuant to this Section 8, the principal amount of each Note to be prepaid shall mature and become due and payable on the date fixed for such prepayment, together with interest on such principal amount accrued to such date and the applicable Make-Whole Amount, if any. From and after such date, unless the Company shall fail to pay such principal amount when so due and payable, together with the interest and Make-Whole Amount, if any, as aforesaid, interest on such principal amount shall cease to accrue. Any Note paid or prepaid in full shall be surrendered to the Company and cancelled and shall not be reissued, and no Note shall be issued in lieu of any prepaid principal amount of any Note.

Section 8.5. Purchase of Notes . The Company will not and will not permit any Affiliate to purchase, redeem, prepay or otherwise acquire, directly or indirectly, any of the outstanding Notes except (a) upon the payment or prepayment of the Notes in accordance with the terms of this Agreement and the Notes or (b) pursuant to an offer to purchase made by the Company or an Affiliate pro rata to the holders of all Notes at the time outstanding upon the same terms and conditions. Any such offer shall provide each holder with sufficient information to enable it to make an informed decision with respect to such offer, and shall remain open for at least thirty (30) Business Days. If the holders of more than 50% of the principal amount of the Notes then outstanding accept such offer, the Company shall promptly notify the remaining holders of such fact and the expiration date for the acceptance by holders of Notes of such offer shall be extended by the number of days necessary to give each such remaining holder at least fifteen (15) Business Days from its receipt of such notice to accept such offer. The Company will promptly cancel all Notes acquired by it or any Affiliate pursuant to any payment, prepayment or purchase of Notes pursuant to any provision of this Agreement and no Notes may be issued in substitution or exchange for any such Notes.

Section 8.6. Make-Whole Amount . The term “Make-Whole Amount” means, with respect to any Note, an amount equal to the excess, if any, of the Discounted Value of the Remaining Scheduled Payments with respect to the Called Principal of such Note over the amount of such Called Principal, provided that the Make-Whole Amount may in no event be less than zero. For the purposes of determining the Make-Whole Amount, the following terms have the following meanings:

“Called Principal” means, with respect to any Note, the principal of such Note that is to be prepaid pursuant to Section 8.2 or has become or is declared to be immediately due and payable pursuant to Section 12.1, as the context requires.

“Discounted Value” means, with respect to the Called Principal of any Note, the amount obtained by discounting all Remaining Scheduled Payments with respect to such Called Principal from their respective scheduled due dates to the Settlement Date with respect to such Called Principal, in accordance with accepted financial practice and at a discount factor (applied on the same periodic basis as that on which interest on the Notes is payable) equal to the Reinvestment Yield with respect to such Called Principal.

15

Exhibit 10(x) (continued)

“Reinvestment Yield” means, with respect to the Called Principal of any Note, the sum of (a) .30% plus (b) the yield to maturity implied by (i) the ask yields reported, as of the close of business on the second Business Day preceding the Settlement Date with respect to such Called Principal, on the “HP” (historical price) pages for actively traded U.S. Treasury securities from the “PX1” page of the Bloomberg Financial Markets screens, having a maturity equal to the Remaining Average Life of such Called Principal as of such Settlement Date, or (ii) if such yields are not reported as of such time or the yields reported as of such time are not ascertainable, the Treasury Constant Maturity Series Yields reported, for the latest day for which such yields have been so reported as of the second Business Day preceding the Settlement Date with respect to such Called Principal, in U.S. Federal Reserve Statistical Release H.15 (519) (or any comparable successor publication) for actively traded U.S. Treasury securities having a constant maturity equal to the Remaining Average Life of such Called Principal as of such Settlement Date. Such implied yield will be determined, if necessary, by (1) converting U.S. Treasury bill quotations to bond-equivalent yields in accordance with accepted financial practice and (2) interpolating linearly between (A) the actively traded U.S. Treasury security with the maturity closest to and greater than the Remaining Average Life and (B) the actively traded U.S. Treasury security with the maturity closest to and less than the Remaining Average Life.

“Remaining Average Life” means, with respect to any Called Principal, the number of years (calculated to the nearest one-twelfth year) obtained by dividing

(i) such Called Principal into

(ii) the sum of the products obtained by multiplying

(A) the principal component of each Remaining Scheduled Payment with respect to such Called Principal by

(B) the number of years (calculated to the nearest one-twelfth year) that will elapse between the Settlement Date with respect to such Called Principal and the scheduled due date of such Remaining Scheduled Payment.

“Remaining Scheduled Payments” means, with respect to the Called Principal of any Note, all payments of such Called Principal and interest thereon that would be due after the Settlement Date with respect to such Called Principal if no payment of such Called Principal were made prior to its scheduled due date, provided that if such Settlement Date is not a date on which interest payments are due to be made under the terms of the Notes, then the amount of the next succeeding scheduled interest payment will be reduced by the amount of interest accrued to such Settlement Date and required to be paid on such Settlement Date pursuant to Section 8.2 or 12.1.

16

Exhibit 10(x) (continued)

“Settlement Date” means, with respect to the Called Principal of any Note, the date on which such Called Principal is to be prepaid pursuant to Section 8.2 or has become or is declared to be immediately due and payable pursuant to Section 12.1, as the context requires.

Section 8.7. Change in Control.

(a) Notice of Change in Control or Control Event. The Company will, within fifteen (15) Business Days after any Responsible Officer has knowledge of the occurrence of any Change in Control or Control Event, give written notice of such Change in Control or Control Event to each holder of Notes unless notice in respect of such Change in Control (or the Change in Control contemplated by such Control Event) shall have been given pursuant to Section 8.7(b). If a Change in Control has occurred, such notice shall contain and constitute an offer to prepay Notes as described in Section 8.7(c) and shall be accompanied by the certificate described in Section 8.7(g).

(b) Condition to Company Action. The Company will not take any action that consummates or finalizes a Change in Control unless at least 30 days prior to such action it shall have given to each holder of Notes written notice containing and constituting an offer to prepay Notes as described in Section 8.7(c), accompanied by the certificate described in Section 8.7(g), and contemporaneously with such action, it prepays all Notes required to be prepaid in accordance with this Section 8.7.

(c) Offer to Prepay Notes. The offer to prepay Notes contemplated by Section 8.7(a) and Section 8.7(b) shall be an offer to prepay, in accordance with and subject to this Section 8.7, all, but not less than all, the Notes held by each holder (in this case only, “holder” in respect of any Note registered in the name of a nominee for a disclosed beneficial owner shall mean such beneficial owner) on a date specified in such offer (the “Proposed Prepayment Date”). If such Proposed Prepayment Date is in connection with an offer contemplated by Section 8.7(a), such date shall be not less than 45 days and not more than 60 days after the date of such offer. If the Proposed Prepayment Date shall not be specified in such offer, the Proposed Prepayment Date shall be the 60th day after the date of such offer.

(d) Acceptance and Rejection. A holder of Notes may accept the offer to prepay made pursuant to this Section 8.7 by causing a notice of such acceptance to be delivered to the Company at least fifteen (15) days prior to the Proposed Prepayment Date. The failure by a holder of Notes to respond to an offer to prepay made pursuant to this Section 8.7 shall be deemed to constitute an acceptance of such offer by such holder.

(e) Prepaymen t. Prepayment of the Notes to be prepaid pursuant to this Section 8.3 shall be at 100% of the principal amount of such Notes, together with interest on such Notes accrued to the date of prepayment. The prepayment shall be made on the Proposed Prepayment Date except as provided in Section 8.7(f).

17

Exhibit 10(x) (continued)

(f) Deferral of Obligation to Purchase. The obligation of the Company to prepay Notes pursuant to the offers accepted in accordance with Section 8.7(d) is subject to the occurrence of the Change in Control in respect of which such offers and acceptances shall have been made. In the event that such Change in Control does not occur on the Proposed Prepayment Date in respect thereof, the prepayment shall be deferred until and shall be made on the date on which such Change in Control occurs. The Company shall keep each holder of Notes reasonably and timely informed of: (i) any such deferral of the date of prepayment; (ii) the date on which such Change in Control and the prepayment are expected to occur; and (iii) any determination by the Company that the efforts to effect such Change in Control have ceased or been abandoned (in which case the offers and acceptances made pursuant to this Section 8.7 in respect of such Change in Control shall be deemed rescinded).

(g) Officer’s Certificate. Each offer to prepay the Notes pursuant to this Section 8.7 shall be accompanied by a certificate, executed by a Senior Financial Officer and dated the date of such offer, specifying: (i) the Proposed Prepayment Date; (ii) that such offer is made pursuant to this Section 8.7; (iii) the principal amount of each Note offered to be prepaid; (iv) the interest that would be due on each Note offered to be prepaid, accrued to the Proposed Prepayment Date; (v) the last date upon which the offer can be accepted or rejected, and setting forth the consequences of failing to provide an acceptance or rejection, as provided in Section 8.7(d); (vi) that the conditions of this Section 8.7 have been fulfilled; and (vii) in reasonable detail, the nature and date or proposed date of the Change in Control.

S ECTION  9. A FFIRMATIVE C OVENANTS .

The Company covenants that so long as any of the Notes are outstanding:

Section 9.1. Compliance with Law . The Company will and will cause each of its Subsidiaries to comply with all laws, ordinances or governmental rules or regulations to which each of them is subject, including, without limitation, Environmental Laws, and will obtain and maintain in effect all licenses, certificates, permits, franchises and other governmental authorizations necessary to the ownership of their respective properties or to the conduct of their respective businesses, in each case to the extent necessary to ensure that non-compliance with such laws, ordinances or governmental rules or regulations or failures to obtain or maintain in effect such licenses, certificates, permits, franchises and other governmental authorizations would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect on the business, operations, affairs, financial condition, properties or assets of the Company and its Subsidiaries taken as a whole.

Section 9.2. Insurance . The Company will and will cause each of its Subsidiaries to maintain, with financially sound and reputable