Exhibit 1.1

DYAX CORP.

Up to 6,315,000 Shares of Common Stock

PLACEMENT AGENCY AGREEMENT

May 19, 2005

Deutsche Bank Securities Inc.
SG Cowen & Co., LLC

c/o Deutsche Bank Securities Inc.
60 Wall Street
New York, New York  10019

Ladies and Gentlemen:

Dyax Corp., a Delaware corporation (the “Company”), proposes, subject to the terms and conditions stated herein, to issue and sell up to 6,315,000 shares (the “Shares”) of common stock, par value $0.01 per share (the “Common Stock”), to certain investors (collectively, the “Investors”).  The Company desires to engage you as its placement agents (the “Placement Agents”) in connection with such issuance and sale.  The Shares are described more fully in the Registration Statement (as hereinafter defined).

The Company hereby confirms as follows its agreements with the Placement Agents:

1.             Agreement to Act as Placement Agents.  On the basis of the representations, warranties and agreements of the Company herein contained and subject to all the terms and conditions of this Agreement, the Placement Agents agree to act as the Company’s exclusive placement agents in connection with the issuance and sale, on a best efforts basis, by the Company of the Shares to the Investors.  Upon the occurrence of the Closing (as hereinafter defined), the Company shall pay to the Placement Agents 6.0% of the proceeds received by the Company from the sale of the Shares as set forth on the cover page of the Prospectus (as hereinafter defined).

2.             Delivery and Payment.  At 10:00 a.m., New York City time, on May 24, 2005, or at such other time on such other date as may be agreed upon by the Company and the Placement Agents (such date is hereinafter referred to as the “Closing Date”), the Placement Agents shall cause the Investors to wire an amount equal to the price per share as shown on the cover page of the Prospectus (as hereinafter defined) to an account designated by the Company and the Company shall deliver the Shares to the Investors, which delivery shall be made through the facilities of The Depository Trust Company.  The closing (the “Closing”) shall take place at the office of Morrison & Foerster LLP at 1290 Avenue of the Americas, New York, New York 10104.  All actions taken at the Closing shall be deemed to have occurred simultaneously.

3.             Representations and Warranties of the Company.  The Company represents and warrants to the Placement Agents that:

(a)           Registration Statement.  The Company has filed with the Securities and Exchange Commission (the “Commission”) a “shelf” registration statement on Form S-3 (Registration No. 333-113500), which has become effective, relating to the Common Stock of the Company, under the Securities Act of 1933, as amended (the “Act”), and the rules and regulations (collectively referred to as the “Rules and Regulations”) of the Commission promulgated thereunder.  The registration statement, as amended as of the date of this Agreement, including the exhibits and information (if any) deemed to be part of the registration statement pursuant to Rule 430A or 434(d) under the Act, is hereinafter referred to as the “Registration Statement.”  No stop order suspending the effectiveness of the Registration Statement has been issued and, to the Company’s knowledge, no proceeding for that purpose has been initiated or threatened by the Commission.  The Company, if required by the Rules and Regulations of the Commission, proposes to file the Prospectus (as defined below) with the Commission pursuant to Rule 424(b) of the Rules and Regulations.  The Prospectus, in the form in which it is to be filed with the Commission pursuant to Rule 424(b) of the Rules and Regulations, or, if the Prospectus is not to be filed with the Commission pursuant to Rule 424(b), the Prospectus in the form included as part of the Registration Statement at the time the Registration Statement became effective, is hereinafter referred to as the “Prospectus,” except that if any revised prospectus or prospectus supplement shall be provided to the Placement Agents by the Company for use in connection with the offering and sale of the Shares which differs from the Prospectus (whether or not such revised prospectus or prospectus supplement is required to be filed by the Company pursuant to Rule 424(b) of the Rules and Regulations), the term “Prospectus” shall refer to such revised prospectus or prospectus supplement, as the case may be, from and after the time it is first provided to the Placement Agents for such use.  Any preliminary prospectus or prospectus subject to completion included in the Registration Statement or filed with the Commission pursuant to Rule 424 under the Act is hereafter called a “Preliminary Prospectus.”  Any reference herein to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 which were filed under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) on or before the last to occur of the effective date of the Registration Statement, the date of the Preliminary Prospectus, or the date of the Prospectus, and any reference herein to the terms “amend,” “amendment” or “supplement” with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include (i) the filing of any document under the Exchange Act after the effective date of the Registration Statement, the date of such Preliminary Prospectus or the date of the Prospectus, as the case may be, which is incorporated therein by reference and (ii) any such document so filed.

(b)           Registration Statement and Prospectus.  When the Registration Statement became effective, upon the filing or first delivery to the Investors of the Prospectus, as of the date hereof, and at the Closing Date, the Registration Statement (and any post-effective amendment thereto) and the Prospectus (as amended or as supplemented if the Company shall have filed with the Commission any amendment or supplement to the Registration Statement or the Prospectus) complied and will comply in all material respects with the Act and the Rules and Regulations, and did not 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 (in the light

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of the circumstances under which they were made, in the case of the Prospectus) not misleading, each Preliminary Prospectus, as of the date filed with the Commission, did not include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; except that no representation or warranty is made in this Section 3(b) with respect to statements or omissions made in reliance upon and in conformity with written information furnished to the Company expressly for inclusion in any Preliminary Prospectus, the Registration Statement, or the Prospectus, or any amendment or supplement thereto, as stated in Section 7(b) hereof.  The Company has not distributed any offering material in connection with the offering and sale of the Shares, other than the Registration Statement, the Preliminary Prospectus and the Prospectus.

(c)           Subsidiaries.  The Company has no significant subsidiaries (as such term is defined in Rule 1-02 of Regulation S-X promulgated by the Commission).  The Company owns, directly or indirectly, all of the capital stock of Dyax Holdings B.V., Dyax B.V., and Dyax S.A. (the “Subsidiaries”) free and clear of any lien, charge, security interest, encumbrance, right of first refusal or other restriction, and all the issued and outstanding shares of capital stock of the Subsidiaries are validly issued and are fully paid, nonassessable and free of preemptive and similar rights.

(d)           Financial Statements.  The consolidated financial statements and the related notes thereto included or incorporated by reference in the Registration Statement and the Prospectus comply with the applicable requirements of the Act and the Exchange Act, as applicable, and present fairly, the consolidated financial position of the Company as of the dates indicated and its results of operations and its consolidated cash flows for the periods specified; such financial statements and the related notes thereto have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods covered thereby (except as otherwise stated therein and subject, in the case of unaudited financial statements, to the absence of footnotes and normal year end adjustments), and the other financial information included or incorporated by reference in the Registration Statement and the Prospectus has been derived from the accounting records of the Company and its Subsidiaries and presents fairly the information shown thereby.  No other consolidated financial statements or schedules of the Company or any other entity are required by the Act or the Rules and Regulations to be included in the Registration Statement or the Prospectus.

(e)           No Material Adverse Change.  Except as set forth in or otherwise contemplated by the Registration Statement or the Prospectus, since the date of the most recent financial statements of the Company included or incorporated by reference in the Registration Statement and the Prospectus and prior to Closing, (i) there has not been any change in the capital stock of the Company (except for changes in the number of outstanding shares of Common Stock of the Company due to the issuance of shares, including without limitation shares issued under the Company’s employee stock purchase plan, upon the exercise or conversion of securities exercisable for, or convertible into, shares of Common Stock outstanding on the date hereof) or long-term debt of the Company or of its Subsidiaries or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development that would reasonably be expected to result in a material adverse change, in or affecting the business, properties, management, consolidated

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financial position, stockholders’ equity, or results of operations of the Company and its Subsidiaries taken as a whole (a “Material Adverse Change”); (ii) neither the Company nor its Subsidiaries have entered into any transaction or agreement, not in the ordinary course of business, that is material to the Company and its Subsidiaries taken as a whole or incurred or will incur any liability or obligation, direct or contingent, not in the ordinary course of business, that is material to the Company and its Subsidiaries taken as a whole; and (iii) neither the Company nor its Subsidiaries have sustained any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority.

(f)            Organization.  The Company and its Subsidiaries are duly organized, validly existing as a corporation and in good standing under the laws of their respective jurisdictions of organization.  The Company and its Subsidiaries are duly licensed or qualified as a foreign corporation for transaction of business and in good standing under the laws of each other jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such license or qualification, and have all corporate power and authority necessary to own or hold their respective properties and to conduct their respective businesses as described in the Registration Statement and the Prospectus, except where the failure to be so qualified or in good standing or have such power or authority would not, individually or in the aggregate, have a material adverse effect or would reasonably be expected to have a material adverse effect on the business, properties, prospects, management, consolidated financial position, stockholders’ equity or results of operations of the Company and its Subsidiaries taken as a whole (a “Material Adverse Effect”).

(g)           Capitalization.  The issued and outstanding shares of capital stock of the Company have been validly issued, are fully paid and nonassessable and, other than as disclosed in or contemplated by the Registration Statement or the Prospectus, are not subject to any preemptive or similar rights.  The Company has an authorized, issued and outstanding capitalization as set forth in the Registration Statement and the Prospectus as of the dates referred to therein (other than the grant of additional options under the Company’s existing stock option plans, or changes in the number of outstanding shares of Common Stock of the Company due to the issuance of shares under the Company’s employee stock purchase plan or upon the exercise or conversion of securities exercisable for, or convertible into, shares of Common Stock outstanding on the date hereof) and such authorized capital stock conforms to the description thereof set forth in the Registration Statement and the Prospectus.  The description of the securities of the Company in the Registration Statement and the Prospectus is complete and accurate in all material respects.  Except as disclosed in or contemplated by the Registration Statement or the Prospectus, as of the date referred to therein, the Company did not have outstanding any options to purchase, or any rights or warrants to subscribe for, or any securities or obligations convertible into, or exchangeable for, or any contracts or commitments to issue or sell, any shares of capital stock or other securities.

(h)           Due Authorization and Enforceability.  The Company has full legal power and authority to enter into this Agreement and any other ancillary agreements associated with the transaction (together, the “Transaction Documents”) and to consummate the transactions contemplated hereby and thereby.  The Transaction Documents have been duly authorized,

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executed and delivered by the Company and constitute legal, valid and binding obligations of the Company enforceable against the Company in accordance with their respective terms except as rights to indemnity and contribution thereunder may be limited by federal or state securities laws and matters of public policy and except as such enforceability may be subject to the effect of applicable bankruptcy, insolvency, reorganization or similar laws affecting creditors’ rights generally and equitable principles of general applicability.

(i)            The Shares.  The Shares have been duly authorized by the Company and, when issued and delivered and paid for as provided herein, will be validly issued, fully paid and nonassessable and will conform to the descriptions thereof in the Prospectus; and the issuance of the Shares is not subject to any preemptive or similar rights that have not been waived.

(j)            No Violation or Default.  Neither the Company nor its Subsidiaries are (i) in violation of its charter or by-laws or similar organizational documents; (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or its Subsidiaries are a party or by which the Company or its Subsidiaries are bound or to which any of the property or assets of the Company or its Subsidiaries are subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of each of clauses (ii) and (iii) above, for any such violation or default that would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(k)           No Conflicts.  The execution, delivery and performance by the Company of each of the Transaction Documents, the issuance and sale by the Company of the Shares and the consummation by the Company of the transactions contemplated by the Transaction Documents will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or its Subsidiaries pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or its Subsidiaries are a party or by which the Company or its Subsidiaries are bound or to which any of the property or assets of the Company or its Subsidiaries are subject; (ii) result in any violation of the provisions of the charter or by-laws or similar organizational documents of the Company or its Subsidiaries; or (iii) result in the violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of each of clauses (i) and (iii) above, for any such conflict, breach, violation, default, lien, charge or encumbrance that would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(l)            No Consents Required.  No consent, approval, authorization, order, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by the Company of each of the Transaction Documents, the issuance and sale by the Company of the Shares and the consummation by the Company of the transactions contemplated by the Transaction Documents, except for the registration of the Shares under the Act and such consents, approvals, authorizations, orders and registrations or qualifications as may be required under applicable state securities laws or by the

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by-laws and rules of the National Association of Securities Dealers, Inc. (“NASD”) in connection with the distribution of the Shares by the Placement Agents.

(m)          Legal Proceedings.  There are no legal, governmental or regulatory actions, suits or proceedings pending, nor, to the Company’s knowledge, any legal, governmental or regulatory investigations, to which the Company or its Subsidiaries are a party or to which any property of the Company or its Subsidiaries is the subject that, individually or in the aggregate, if determined adversely to the Company or its Subsidiaries, would reasonably be expected to have a Material Adverse Effect or materially and adversely affect the ability of the Company to perform its obligations under the Transaction Documents; to the Company’s knowledge, no such actions, suits or proceedings are threatened or contemplated by any governmental or regulatory authority or threatened by others; and (i) there are no current or pending legal, governmental or regulatory investigations, actions, suits or proceedings that are required under the Act to be described in the Prospectus that are not so described; and (ii) there are no contracts or other documents that are required under the Act to be filed as exhibits to the Registration Statement that are not so filed.

(n)           Independent Accountants.  PricewaterhouseCoopers LLP, who have audited certain consolidated financial statements of the Company, is an independent registered public accounting firm (the “Accountants”) with respect to the Company as required by the Act.

(o)           Title to Real and Personal Property.  The Company and its Subsidiaries own no real property.  Except as disclosed in Notes 4 and 8 to the Company’s consolidated financial statements for the year ended December 31, 2004 that are incorporated by reference into the Registration Statement, the Company and its Subsidiaries have good and valid title to all personal property owned by them, in each case free and clear of all liens, encumbrances and claims except those that (i) do not materially interfere with the use made and proposed to be made of such property by the Company and its Subsidiaries or (ii) would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.  Any real property leased by the Company and its Subsidiaries is held by them under valid, existing and enforceable leases, except those that (A) do not materially interfere with the use made or proposed to be made of such property by the Company or its Subsidiaries or (B) would not be reasonably expected, individually or in the aggregate, to have a Material Adverse Effect.

(p)           Title to Intellectual Property.  The Company and its Subsidiaries own or possess adequate rights to use all patents, patent applications, trademarks, service marks, trade names, trademark registrations, service mark registrations, copyrights, licenses and know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures) (collectively, the “Intellectual Property”), necessary for the conduct of their respective businesses as conducted as of the date hereof, except to the extent that the failure to own or possess adequate rights to use such Intellectual Property would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and the Company and its Subsidiaries have not received any written notice of any claim of infringement or conflict which asserted Intellectual Property rights of others, which infringement or conflict, if the subject of an unfavorable decision, would result in a Material Adverse Effect.

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(q)           No Undisclosed Relationships.  No relationship, direct or indirect, exists between or among the Company or its Subsidiaries, on the one hand, and the directors, officers and stockholders of the Company, on the other, which is required by the Act to be disclosed in the Registration Statement and the Prospectus and is not so disclosed.

(r)            Investment Company Act.  The Company is not and, after giving effect to the offering and sale of the Shares to be sold by the Company and the application of the proceeds thereof as described in the Prospectus, will not be an “investment company” within the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission promulgated thereunder.

(s)           Taxes.  The Company and its Subsidiaries have filed all federal, state, local and foreign tax returns (or timely filed applicable extensions therefor) which have been required to be filed and paid all taxes shown thereon through the date hereof, to the extent that such taxes have become due and are not being contested in good faith; and, except as otherwise disclosed in or contemplated by the Registration Statement or the Prospectus, no tax deficiency has been determined adversely to the Company or its Subsidiaries which has had, or would reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect.

(t)            Licenses and Permits.  The Company and its Subsidiaries possess or have obtained all licenses, certificates, permits and other authorizations issued by, and have made all declarations and filings with, the appropriate federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in the Registration Statement and the Prospectus (the “Permits”), except where the failure to possess, obtain or make the same would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and except as disclosed in or contemplated by the Registration Statement or the Prospectus, neither the Company nor its Subsidiaries have received written notice of any proceeding relating to revocation or modification of any such Permit or has any reason to believe that such Permit will not be renewed in the ordinary course, except where the failure to obtain any such renewal would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(u)           No Labor Disputes.  No labor disturbance by or dispute with employees of the Company or its Subsidiaries exists or, to the knowledge of the Company, is threatened which would reasonably be expected to result in a Material Adverse Effect.

(v)           Compliance With Environmental Laws.  The Company and its Subsidiaries (i) are in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, decisions and orders relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (collectively, “Environmental Laws”); (ii) have received and are in compliance with all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their respective businesses as described in the Registration Statement and the Prospectus; and (iii) have not received notice of any actual or potential liability for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, except, in the case of any of clauses (i), (ii) or (iii) above, for any such failure to comply or

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failure to receive required permits, licenses, other approvals or liability as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(w)          Compliance With ERISA.  Each material employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), that is maintained, administered or contributed to by the Company or any of its affiliates for employees or former employees of the Company and its Subsidiaries has been maintained in material compliance with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Internal Revenue Code of 1986, as amended (the “Code”); no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred which would result in a material liability to the Company with respect to any such plan excluding transactions effected pursuant to a statutory or administrative exemption; and for each such plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no “accumulated funding deficiency” as defined in Section 412 of the Code has been incurred, whether or not waived, and the fair market value of the assets of each such plan (excluding for these purposes accrued but unpaid contributions) exceeds the present value of all benefits accrued under such plan determined using reasonable actuarial assumptions.

(x)            Listing.  The Company has not, in the two years preceding the date hereof, received any notice (written or oral) from the Nasdaq National Market, any stock exchange, market or trading facility on which the Common Stock is or has been listed (or on which it has been quoted) to the effect that the Company is not in compliance with the listing or maintenance requirements of such exchange, market or trading facility.  The Company shall comply with all requirements of the Nasdaq National Market with respect to the issuance of Shares and shall use its best efforts to have the Shares listed on the Nasdaq National Market on or before the Closing Date.

(y)           Sarbanes-Oxley Act.  There is and has been no failure on the part of the Company, or to its knowledge after due inquiry, and any of the Company’s directors or officers, in their capacities as such, to comply with any applicable provisions of the Sarbanes Oxley Act of 2002 and the rules and regulations promulgated therewith (the “Sarbanes Oxley Act”).  Each of the principal executive officer and the principal financial officer of the Company (or each former principal executive officer of the Company and each former principal financial officer of the Company as applicable) has made all certifications required by Sections 302 and 906 of the Sarbanes-Oxley Act with respect to all reports, schedules, forms, statements and other documents required to be filed by it with the Commission.  For purposes of the preceding sentence, “principal executive officer” and “principal financial officer” shall have the meanings given to such terms in the Sarbanes-Oxley Act.

(z)            Internal Controls.  The Company and its Subsidiaries maintain systems of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and

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appropriate action is taken with respect to any differences.  The Company has established disclosure controls and procedures (as defined in Exchange Act Rules 13a-14 and 15d-14) for the Company and designed such disclosure controls and procedures to ensure that material information relating to the Company and its Subsidiaries is made known to the certifying officers by others within those entities, particularly during the period in which the Company’s Annual Report on Form 10-K or Quarterly Report on Form 10-Q, as the case may be, is being prepared.  The Company’s certifying officers have evaluated the effectiveness of the Company’s controls and procedures as of the end of the period covered by the Form 10-Q for the quarter ended March 31, 2005 (such date, the “Evaluation Date”).  The Company presented in its Form 10-Q for the quarter ended March 31, 2005 the conclusions of the certifying officers about the effectiveness of the disclosure controls and procedures based on their evaluations as of the Evaluation Date.  Since the Evaluation Date, there have been no significant changes in the Company’s internal controls (as such term is defined in Item 307(b) of Regulation S-K under the Exchange Act) or, to the Company’s knowledge, in other factors that could significantly affect the Company’s internal controls.

(aa)         Operations.  The operations of the Company and its Subsidiaries are and have been conducted at all times in material compliance with applicable financial record keeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions to which the Company or its Subsidiaries are subject, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its Subsidiaries with respect to the Money Laundering Laws is pending or, to the best knowledge of the Company, threatened.

(bb)         Off-Balance Sheet Arrangements.  There are no transactions, arrangements and other relationships between and/or among the Company, and/or, to the knowledge of the Company, any of its affiliates and any unconsolidated entity, including, but not limited to, any structural finance, special purpose or limited purpose entity (each, an “Off Balance Sheet Transaction”) that could reasonably be expected to affect materially the Company’s liquidity or the availability of or requirements for its capital resources, including those Off Balance Sheet Transactions described in the Commission’s Statement about Management’s Discussion and Analysis of Financial Conditions and Results of Operations (Release Nos. 33-8056; 34-45321; FR-61), required to be described in the Prospectus which have not been described as required.

(cc)         Foreign Corrupt Practices.  Neither the Company, nor any of its Subsidiaries, nor, to the knowledge of the Company, any director, officer, agent, employee or other Person acting on behalf of the Company or any of its Subsidiaries have, in the course of its actions for, or on behalf of, the Company (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expenses relating to political activity; (ii) made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; (iii) violated or is in violation of any provision of the U.S. Foreign Corrupt Practices Act of 1977, as amended; or (iv) made any unlawful bribe, rebate, payoff, influence payment, kickback or other unlawful payment to any foreign or domestic government official or employee.

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(dd)         Insurance.  The Company and its Subsidiaries carry, or are covered by, insurance in such amounts and covering such risks as the Company and its Subsidiaries reasonably believe are adequate for the conduct of their respective businesses as described in the Registration Statement and the Prospectus and the value of their properties and as is customary for companies engaged in similar businesses in similar industries.

(ee)         No Broker’s Fees.  Neither the Company nor its Subsidiaries are a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against the Company or its Subsidiaries or the Placement Agents for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Shares.

(ff)           No Registration Rights.  No person has the right to require the Company or its Subsidiaries to register any securities for sale under the Act by reason of the filing of the Registration Statement with the Commission or by reason of the issuance and sale of the Shares, except for rights which have been waived.

(gg)         No Stabilization.  The Company has not taken, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of the Shares.

(hh)         Forward-Looking Statements.  No forward-looking statement (within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act) (a “Forward Looking Statement”) contained in the Registration Statement and the Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(ii)           Contracts.  All contracts that are filed as exhibits to the Company’s Annual Report on Form 10-K for the year ended December 31, 2004 have been duly authorized, executed and delivered by the Company, constitute valid and binding agreements of the Company, and are enforceable against the Company in accordance with the terms thereof, subject to the effect of applicable bankruptcy, insolvency or similar laws affecting creditors’ rights generally and equitable principles of general applicability.

(jj)           Certificates.  No statement, representation or warranty made in the certificate to be delivered to the Placement Agents pursuant to Section 6(g) below will be, when made, inaccurate, untrue or incorrect in any material respect.

4.             Further Agreements of the Company.  The Company covenants and agrees with the Placement Agents that:

(a)           Effectiveness.  The Registration Statement has become effective, and if Rule 430A is used or the filing of the Prospectus is otherwise required under Rule 424(b), the Company will file the Prospectus (properly completed if Rule 430A has been used) pursuant to Rule 424(b) within the prescribed time period and will provide a copy of such filing to the Placement Agents promptly following such filing.

(b)           Amendments or Supplements.  The Company will not, during such period as the Prospectus would be required by law to be delivered in connection with sales of the Shares by an

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underwriter or dealer in connection with the offering contemplated by this Agreement, file any amendment or supplement to the Registration Statement or the Prospectus, except as required by law, unless a copy thereof shall first have been submitted to the Placement Agents within a reasonable period of time prior to the filing thereof and the Placement Agents shall not have reasonably objected thereto in good faith.

(c)           Notice to Placement Agents.  The Company will notify the Placement Agents promptly, and will, if requested, confirm such notification in writing, (1) when any post-effective amendment to the Registration Statement becomes effective, but only during the period mentioned in Section 4(b); (2) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or for additional information, but only during the period mentioned in Section 4(b); (3) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or the initiation of any proceedings for that purpose or the threat thereof, but only during the period mentioned in Section 4(b); (4) of becoming aware of the occurrence of any event during the period mentioned in Section 4(b) that in the judgment of the Company makes any statement made in the Registration Statement or the Prospectus untrue in any material respect or that requires the making of any changes in the Registration Statement or the Prospectus in order to make the statements therein, in light of the circumstances in which they are made, not misleading; and (5) of receipt by the Company of any notification with respect to any suspension of the qualification of the Shares for offer and sale in any jurisdiction.  If at any time the Commission shall issue any order suspending the effectiveness of the Registration Statement in connection with the offering contemplated hereby, the Company will make every reasonable effort to obtain the withdrawal of any such order at the earliest possible moment.  If the Company has omitted any information from the Registration Statement, pursuant to Rule 430A, it will use its best efforts to comply with the provisions of and make all requisite filings with the Commission pursuant to said Rule 430A and to notify the Placement Agents promptly of all such filings.

(d)           Ongoing Compliance of the Prospectus.  If, at any time when a Prospectus relating to the Shares is required to be delivered under the Act, the Company becomes aware of the occurrence of any event as a result of which the Prospectus, as then amended or supplemented, would, in the reasonable judgment of counsel to the Company or counsel to the Placement Agents, include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, or the Registration Statement, as then amended or supplemented, would, in the reasonable judgment of counsel to the Company or counsel to the Placement Agents, include any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein not misleading, or if for any other reason it is necessary, in the reasonable judgment of counsel to the Company or counsel to the Placement Agents, at any time to amend or supplement the Prospectus or the Registration Statement to comply with the Act or the Rules and Regulations, the Company will promptly notify the Placement Agents and, subject to Section 4(b) hereof, will promptly prepare and file with the Commission, at the Company’s expense, an amendment to the Registration Statement or an amendment or supplement to the Prospectus that corrects such statement or omission or effects such compliance and will deliver to the Placement Agents, without charge, such number of copies thereof as the Placement Agents may reasonably request.  The Company consents to the

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use of the Prospectus or any amendment or supplement thereto by the Placement Agents, and the Placement Agents agree to provide to each Investor, prior to the Closing, a copy of the Prospectus and any amendments or supplements thereto.

(e)           Delivery of Copies.  The Company will furnish to the Placement Agents and their counsel, without charge (i) one copy of the Registration Statement, including financial statements and schedules, and all exhibits thereto and (ii) so long as a prospectus relating to the Shares is required to be delivered under the Act, as many copies of each Preliminary Prospectus or the Prospectus or any amendment or supplement thereto as the Placement Agents may reasonably request.

(f)            Compliance with Undertakings.  The Company will comply with all the undertakings contained in the Registration Statement.

(g)           Blue Sky Compliance.  Prior to the sale of the Shares to the Investors, the Company will cooperate with the Placement Agents and their counsel in connection with the registration or qualification of the Shares for offer and sale under the state securities or Blue Sky laws of such jurisdictions as the Placement Agents may reasonably request; provided, that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action which would subject it to general service of process in any jurisdiction where it is not now so subject.

(h)           Use of Proceeds.  The Company will apply the net proceeds from the offering and sale of the Shares in the manner set forth in the Prospectus under the caption “Use of Proceeds.”

(i)            Exchange.  The Company will use its best efforts to ensure that the Shares are quoted on the Nasdaq National Market at the time of the Closing.

(j)            Reports.  For a period of three years from the Closing Date, the Company will furnish to the Placement Agents, as soon as they are available, copies of all reports or other communications (financial or other) furnished to holders of the Shares, other than any such reports or communications filed with the Commission pursuant to the Commission’s EDGAR system.

(k)           Lock-up Period.  For a period of 60 days after the date hereof, the Company will not (1) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock; or (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise, without the prior written consent of Deutsche Bank Securities Inc. and SG Cowen & Co., LLC, other than (i) the Shares to be sold hereunder, (ii) securities issued pursuant to stock option plans, deferred compensation plans, restricted stock plans and employee stock purchase plans existing on, or upon the conversion or exchange of convertible or exchangeable securities outstanding as of, the date of this Agreement; (iii) the issuance by the Company of any

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shares of Common Stock as consideration for mergers, acquisitions, other business combinations, or strategic alliances, occurring after the date of this Agreement, provided that each recipient of shares pursuant to this clause (iii) agrees that all such shares remain subject to restrictions substantially similar to those contained in this subsection; (iv) the offer, issuance or sale of any securities of the Company in exchange for any “underwater” options of the Company; or (v) the purchase or sale of the Company’s securities pursuant to a plan, contract or instruction that satisfies all of the requirements of Rule 10b5-1(c)(1)(i)(B) that was in effect prior to the date hereof.

5.             Expenses.  Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay all costs and expenses incident to the performance of the obligations of the Company under this Agreement, including but not limited to costs and expenses of or relating to (i) the preparation, printing and filing of the Registration Statement (including each pre- and post-effective amendment thereto) and exhibits thereto, each Preliminary Prospectus, the Prospectus and any amendment or supplement to the Prospectus, (ii) the preparation and delivery of certificates representing the Shares, (iii) furnishing (including costs of shipping and mailing) such copies of the Registration Statement (including all pre- and post-effective amendments thereto), the Prospectus and any Preliminary Prospectus, and all amendments and supplements to the Prospectus, as may be requested for use in connection with the direct placement of the Shares, (iv) the quotation of the Common Stock on the Nasdaq National Market, (v) the registration or qualification of the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions designated pursuant to Section 4(g), including the preparation and printing of preliminary, supplemental and final Blue Sky memoranda, (vi) fees, disbursements and other charges of counsel to the Company, and (vii) fees and disbursements of the Accountants incurred in delivering the letter(s) described in 6(f) of this Agreement.  In addition, whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company shall reimburse the Placement Agents for fees and expenses (including the fees, disbursements and other charges of legal counsel to the Placement Agents), up to a maximum of $75,000.

6.             Conditions of the Obligations of the Placement Agent.  The obligations of the Placement Agents hereunder are subject to the following conditions:

(a)           (i)  No stop order suspending the effectiveness of the Registration Statement or the qualification or registration of the Shares under the securities or Blue Sky laws of any jurisdiction shall be in effect and no proceedings for that purpose shall be pending or threatened by any securities or other governmental authority (including, without limitation, the Commission), (ii) any request for additional information on the part of the staff of any securities or other governmental authority (including, without limitation, the Commission) shall have been complied with to the satisfaction of the staff of the Commission or such authorities and (iii) after the date hereof no amendment or supplement to the Registration Statement or the Prospectus shall have been filed unless a copy thereof was first submitted to the Placement Agents and the Placement Agents did not reasonably object thereto in good faith.

(b)           Since the respective dates as of which information is given in the Registration Statement and the Prospectus, (i) there shall not have been a Material Adverse Change whether or not arising from transactions in the ordinary course of business, in each case other than as set

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forth in or contemplated by the Registration Statement or the Prospectus, and (ii) the Company shall not have sustained any material loss or interference with its business or properties from fire, explosion, flood or other casualty, whether or not covered by insurance, or from any labor dispute or any court or legislative or other governmental action, order or decree, which is not set forth in the Registration Statement or the Prospectus, if in the judgment of the Placement Agents any such development makes it impracticable or inadvisable to consummate the sale and delivery of the Shares to Investors at the public offering price.

(c)           Since the respective dates as of which information is given in the Registration Statement and the Prospectus, there shall have been no litigation or other proceeding instituted against the Company or any of its officers or directors in their capacities as such, before or by any federal, state or local court, commission, regulatory body, administrative agency or other governmental body, domestic or foreign, which litigation or proceeding is reasonably expected by management to have a Material Adverse Effect.

(d)           Each of the representations and warranties of the Company contained herein shall be true and correct at the Closing Date, as if made on such date, and all covenants and agreements herein contained to be performed on the part of the Company and all conditions herein contained to be fulfilled or complied with by the Company at or prior to the Closing Date shall have been duly performed, fulfilled or complied with.

(e)           The Placement Agents shall have received an opinion, dated the Closing Date, of Palmer & Dodge LLP, counsel to the Company, in form and substance reasonably satisfactory to the Placement Agents, with respect to the matters set forth in Exhibit A hereto.

(f)            Concurrently with the execution and delivery of this Agreement, or, if the Company elects to rely on Rule 430A, on the date of the Prospectus, the Accountants shall have furnished to the Placement Agents a letter, dated the date of its delivery (the “Original Letter”), addressed to the Placement Agents and in form and substance reasonably satisfactory to the Placement Agents, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters.  At the Closing Date, the Accountants shall have furnished to the Placement Agents a letter, dated the date of its delivery, which shall confirm, on the basis of a review in accordance with the procedures set forth in the Original Letter, that nothing has come to their attention during the period from the date of the Original Letter referred to in the prior sentence to a date (specified in the letter) not more than five days prior to the Closing Date which would require any change in the Original Letter if it were required to be dated and delivered at the Closing Date.

(g)           At the Closing Date, there shall be furnished to the Placement Agents a certificate, dated the date of its delivery, signed by each of the Chief Executive Officer and the Chief Financial Officer of the Company, each in his capacity as such, in form and substance reasonably satisfactory to the Placement Agents to the effect that each signer has carefully examined the Registration Statement and the Prospectus and that to each of such person’s knowledge:

(i)            (A) As of the date of such certificate, (x) the Registration Statement does not contain any untrue statement of a material fact or omit to state a material fact required

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to be stated therein or necessary in order to make the statements therein not misleading and (y) the Prospectus does not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading and (B) no event has occurred as a result of which it is necessary to amend or supplement the Prospectus in order to make the statements therein not untrue or misleading in any material respect.

(ii)           Each of the representations and warranties of the Company contained in this Agreement are true and correct as if such representations and warranties were made on the Closing Date.

(iii)          Each of the covenants and agreements required in this Agreement to be performed by the Company on or prior to the Closing Date and each condition required herein to be fulfilled or complied with by the Company on or prior to the Closing Date has been duly performed, fulfilled or complied with.

(iv)          No stop order suspending the effectiveness of the Registration Statement or of any part thereof has been issued and no proceedings for that purpose have been instituted or, to the Company’s knowledge, are contemplated by the Commission.

(v)           Subsequent to the date of the most recent financial statements in the Prospectus, there has been no material adverse change in the financial position or results of operations of the Company, except as set forth in or contemplated by the Prospectus.

(h)           The Shares shall be qualified for sale in such states as the Placement Agents may reasonably request and each such qualification shall be in effect and not subject to any stop order or other proceeding on the Closing Date; provided that in no event shall the Company be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action which would subject it to taxation or general service of process in any jurisdiction where it is not now so subject.

(i)            The Company shall have furnished or caused to be furnished to the Placement Agents such certificates, in addition to those specifically mentioned herein, as the Placement Agent may have reasonably requested as to the accuracy and completeness, at the Closing Date of any statement in the Registration Statement or the Prospectus, as to the accuracy, at the Closing Date of the representations and warranties of the Company, as to the performance by the Company of its obligations hereunder, or as to the fulfillment of the conditions concurrent and precedent to the obligations hereunder of the Placement Agents.

(j)            The Placement Agents shall have received executed “lock-up” agreements, each substantially in the form of Exhibit B hereto, from the executive officers and directors of the Company relating to sales and certain other dispositions of shares of Common Stock or certain other securities, and such lock-up agreements shall be full force and effect on the Closing Date.

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7.             Indemnification and Contribution.

(a)           Indemnification of the Placement Agent.  The Company agrees to indemnify and hold harmless the Placement Agents, its affiliates, directors, officers, employees, agents and each person, if any, who controls such Placement Agents within the meaning of Section 15 of the Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities, joint or several (including, without limitation, reasonable fees of outside legal counsel and other expenses reasonably incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred) that arise out of, or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or the Prospectus (or any amendment or supplement thereto) or any Preliminary Prospectus, or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information furnished to the Company in writing by the Placement Agents expressly for use therein, it being understood and agreed that the only such information furnished by the Placement Agents consists of the information described as such in subsection (b) below.

(b)           Indemnification of the Company.  The Placement Agents agree to indemnify and hold harmless the Company, its affiliates, directors and officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act to the same extent as the indemnity set forth in paragraph (a) above, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information furnished to the Company in writing by the Placement Agents expressly for use in the Registration Statement or the Prospectus (or any amendment or supplement thereto) or any Preliminary Prospectus, it being understood and agreed upon that the only such information furnished by the Placement Agents consists of the last paragraph on the cover page of the Prospectus.

(c)           Notice and Procedures.  If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought, threatened or asserted against any person in respect of which indemnification may be sought pursuant to either paragraph (a) or (b) above, such person (the “Indemnified Person”) shall promptly notify the person against whom such indemnification may be sought (the “Indemnifying Person”) in writing; provided that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under this Section 7 except to the extent that it has been prejudiced thereby; and provided, further, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under this Section 7.  If any such proceeding shall be brought, threatened or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person to represent the Indemnified Person and any others entitled to indemnification pursuant to this Section 7 that the Indemnifying Person may designate in such proceeding and shall pay the fees and expenses of such counsel related to such proceeding, as incurred.  In any such proceeding, any Indemnified Person shall have the

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right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary; (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the Indemnified Person shall have reasonably concluded, which conclusion shall have been confirmed in the reasonable judgment of its counsel, that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them.  It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceeding in the same jurisdiction, be liable for the fees and expenses of more than one separate firm (in addition to any local counsel) for all Indemnified Persons, and that all such fees and expenses shall be paid or reimbursed as they are incurred.  Any such separate firm for the Placement Agents, their affiliates, directors, officers, employees and agents and any control persons of the Placement Agents shall be designated in writing by Deutsche Bank Securities Inc. and SG Cowen & Co., LLC and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company shall be designated in writing by the Company.  The Indemnifying Person shall not be liable for any settlement of any proceeding with respect to which indemnification is available hereunder effected without its written consent, but if any such proceeding is settled with such consent or if there be a final judgment in any such proceeding for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment.  Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel in connection with any such proceeding as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 45 days after receipt by the Indemnifying Person of such request, (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement and (iii) the Indemnified Person shall have given the Indemnifying Person at least 30 days prior notice of its intention to settle.  No Indemnifying Person shall, without the written consent of the Indemnified Person (which consent shall not be unreasonably withheld, conditioned or delayed), effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance reasonably satisfactory to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.

(d)           Contribution.  If the indemnification provided for in paragraphs (a) and (b) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such paragraph, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one

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hand and the Placement Agents on the other from the offering of the Shares or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company on the one hand and the Placement Agents on the other in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations.  The relative benefits received by the Company on the one hand and the Placement Agents on the other shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Shares and the total fee received by the Placement Agents in connection therewith, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate offering price of the Shares.  The relative fault of the Company on the one hand and the Placement Agents on the other 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 or by the Placement Agents and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(e)           Limitation on Liability.  The Company and the Placement Agents agree that it would not be just and equitable if contribution pursuant to this Section 7 were determined by pro rata allocation or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (d) above.  The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses incurred by such Indemnified Person in connection with any such action or claim.  Notwithstanding the provisions of this Section 7, in no event shall the Placement Agents be required to contribute any amount in excess of the fee received by it with respect to the offering of the Shares exceeds the amount of any damages that the Placement Agents have 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.

(f)            Non-Exclusive Remedies.  The remedies provided for in this Section 7 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any Indemnified Person at law or in equity.

8.             Termination.

(a)           The obligations of the Placement Agents under this Agreement may be terminated, in the absolute discretion of the Placement Agents, at any time prior to the Closing Date, by notice to the Company from the Placement Agents, without liability on the part of the Placement Agents to the Company if, prior to delivery and payment for the Shares, (i) trading generally shall have been suspended or materially limited on or by any of the New York Stock Exchange, the American Stock Exchange or the National Association of Securities Dealers, Inc.; (ii) trading of any securities issued or guaranteed by the Company shall have been suspended on any exchange or in any over-the-counter market; (iii) a general moratorium on commercial banking activities shall have been declared by federal or New York State authorities; or (iv) there

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shall have occurred any outbreak or escalation of hostilities within or outside the United States, that, in the judgment of the Placement Agents, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date on the terms and in the manner contemplated by this Agreement and the Prospectus.

(b)           If this Agreement shall be terminated pursuant to any of the provisions hereof (other than a termination of the Placement Agents’ Engagement pursuant to Section 8(a)), or if the sale of the Shares provided for herein is not consummated because any condition to the obligations of the Placement Agents set forth herein is not satisfied or because of any refusal, inability or failure on the part of the Company to perform any agreement herein or comply with any provision hereof, the Company will, subject to demand by the Placement Agents, reimburse them for all reasonable out-of-pocket expenses incurred in connection herewith.

9.             Notices.  Notice given pursuant to any of the provisions of this Agreement shall be in writing and, unless otherwise specified, shall be mailed or delivered (a) if to the Company, at the office of the Company, 300 Technology Square, Cambridge, Massachusetts 02139, Attention: Henry E. Blair (facsimile:  (617) 225-2501), with a copy to Palmer & Dodge LLP, Attention:  Nathaniel S. Gardiner, Esq. (facsimile:  (617) 227-4420), or (b) if to the Placement Agents, at the office of Deutsche Bank Securities Inc., 60 Wall Street, New York, New York 10019, Attention:  Equity Capital Markets (facsimile:  (212) 797-9344) with a copy to General Counsel (facsimile:  (212) 797-4564)), and at the office of SG Cowen & Co., LLC, 1221 Avenue of the Americas, New York, New York 10020, Attention: Geoff Goodman (facsimile:  (212) 278-5503), with a copy to Morrison & Foerster LLP, 1290 Avenue of the Americas, New York, New York, 10104, Attention:  Anna T. Pinedo, Esq. (facsimile:  (212) 468-7900).  Any such notice shall be effective only upon receipt.  Any notice under Section 7 may be made by facsimile or telephone, but if so made shall be subsequently confirmed in writing.

10.           Survival.  The respective representations, warranties, agreements, covenants, indemnities and other statements of the Company and the Placement Agents 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 (i) any investigation made by or on behalf of the Company, any of its officers or directors, the Placement Agents or any controlling person referred to in Section 7 hereof and (ii) delivery of and payment for the Shares.  The respective agreements, covenants, indemnities and other statements set forth in Sections 5, 7 and 8 hereof shall remain in full force and effect, regardless of any termination or cancellation of this Agreement.

11.           Successors.  This Agreement shall inure to the benefit of and shall be binding upon the Placement Agents, the Company and their respective successors and legal representatives, and nothing expressed or mentioned in this Agreement is intended or shall be construed to give any other person any legal or equitable right, remedy or claim under or in respect of this Agreement, or any provisions herein contained, this Agreement and all conditions and provisions hereof being intended to be and being for the sole and exclusive benefit of such persons and for the benefit of no other person except that (i) the indemnification and contribution contained in Sections 7(a) and (d) of this Agreement shall also be for the benefit of the directors, officers, employees and agents of the Placement Agents and any person or persons who control

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the Placement Agents within the meaning of Section 15 of the Act or Section 20 of the Exchange Act and (ii) the indemnification and contribution contained in Sections 7(b) and (d) of this Agreement shall also be for the benefit of the directors of the Company, the officers of the Company who have signed the Registration Statement and any person or persons who control the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act.  No purchaser of Shares shall be deemed to be a successor by reason merely of such purchase.

12.           Applicable Law.  The validity and interpretations of this Agreement, and the terms and conditions set forth herein, shall be governed by and construed in accordance with the laws of the State of New York, without giving effect to the conflicts of laws provisions thereof.

13.           Counterparts.  This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

14.           Entire Agreement.  This Agreement constitutes the entire understanding between the parties hereto as to the matters covered hereby and supersedes all prior understandings, written or oral, relating to such subject matter.

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Please confirm that the foregoing correctly sets forth the agreement between the Company and the Placement Agents.

EXHIBIT A

Matters to be Covered in the Palmer & Dodge LLP Legal Opinion

1.                                       The Company is validly existing as a corporation in good standing under the laws of the State of Delaware.

2.                                       The Company is in good standing as a foreign corporation, is duly licensed or qualified and has the corporate power and authority to own, lease and operate its properties and to conduct its business in each jurisdiction in which the nature of the activities conducted by it or the character of the assets owned or leased by it makes such licensing or qualification necessary.  The Company has corporate power and authority to enter into and perform its obligations under the Placement Agency Agreement.

3.                                       The shares of issued and outstanding capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable; and to our knowledge, none of the outstanding shares of capital stock of the Company was issued in violation of any statutory, contractual preemptive or other similar rights of any securityholder of the Company.

4.                                       The Shares have been duly authorized and, when issued and delivered by the Company pursuant to the Placement Agency Agreement against payment of the consideration set forth on the cover of the Prospectus, will be validly issued, fully paid and non-assessable.

5.                                       The issuance of the Shares is not subject to any statutory preemptive right or, to our knowledge, other similar rights of any securityholder of the Company.

6.                                       The Placement Agency Agreement and the Purchase Agreements have been duly authorized, executed and delivered by the Company.

7.                                       To our knowledge, no stop order suspending the effectiveness of the Registration Statement has been issued under the Securities Act of 1933, as amended (the “Act”) and no proceedings for that purpose have been instituted or are pending or threatened by the Commission.

8.                                       The Registration Statement, including the Prospectus, including each of the documents incorporated by reference therein, and each amendment or supplement to the Registration Statement and Prospectus, as the case may be, including the documents incorporated by reference therein, as of their respective effective or issue dates, or as of the dates they were filed with the Commission, as the case may be (other than the financial statements and supporting schedules included therein or omitted therefrom, as to which we express no opinion), complied as to form in all material respects with the requirements of the Act and the rules and regulations of the Commission promulgated thereunder (the “Rules and Regulations”).

9.                                       To our knowledge, there is not pending or threatened any action, suit, proceeding, inquiry or investigation, to which the Company or any of its Subsidiaries are parties, or to which the property of the Company or its Subsidiaries are subject, before or brought by any court or governmental agency or body, domestic or foreign, that is required to be disclosed in the Prospectus and is not disclosed therein.

10.                                 The information in the Prospectus under the caption “Description of Common Stock” and “Anti-Takeover Effects of Delaware Law,” to the extent it constitutes matters of law or legal conclusions, has been reviewed by us and presents a fair summary.

11.                                 To our knowledge, there are no franchises, contracts, indentures, mortgages, loan agreements, notes, leases or other instruments required to be described or referred to in the Registration Statement or the Prospectus or to be filed as exhibits thereto other than those described or referred to therein or filed or incorporated by reference as exhibits thereto.

12.                                 No filing with, or authorization, approval, consent. license, order. registration, qualification or decree of, any domestic court or governmental authority or agency, domestic or foreign (other than under the Act and the Rules and Regulations, which have been obtained, or as may be required under the securities or blue sky laws of the various states, as to which we express no opinion) is necessary or required in connection with the due authorization, execution and delivery of the Placement Agency Agreement or for the offering, issuance, sale or delivery of the Shares.

13.                                 The execution, delivery and performance of the Transaction Documents and the consummation of the transactions contemplated therein (including the issuance and sale of the Shares to the Investors) and compliance by the Company with its obligations under the Placement Agency Agreement and in connection with the offering, issuance and sale of the Shares to the Investors do not and will not (i) result in a default under agreements to which the Company is a party that are filed as exhibits to the Company’s Annual Report on Form 10-K for the year ended December 31, 2004 (except for such defaults that would not have a Material Adverse Effect), (ii) result in any violation of the provisions of the charter or by-laws of the Company, or (iii) to our knowledge, result in any material violation of any applicable law, statute, rule, regulation, judgment, order, writ or decree of any government, government instrumentality or court, domestic or foreign, having jurisdiction over the Company or any of its assets, properties or operations.

14.                                 The Company is not an “investment company” as such term is defined in the Investment Company Act of 1940, as amended.

In addition, such counsel shall state that while such counsel is not passing upon and does not assume any responsibility for the accuracy, completeness or fairness of the statements contained in the Registration Statement or the Prospectus, or any supplements or amendments thereto, no facts have come to the attention of such counsel which have caused her to believe

that either the Registration Statement or any amendments thereto, at the time the Registration Statement or any such amendments became effective, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading or that the Prospectus, as of the Closing, contained an untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading (it being understood that such counsel need express no belief as to the financial statements, including the notes and schedules thereto, or any other financial or accounting information, or the information regarding the Placement Agents or the method of distribution of the Shares included in the Registration Statement or the Prospectus or any such amendments or supplements thereto).

EXHIBIT B

LOCK UP LETTERS

May   , 2005

Deutsche Bank Securities Inc.
60 Wall Street
New York, New York  10019

SG Cowen & Co., LLC
1221 Avenue of Americas
New York, New York  10020

Ladies and Gentlemen:

The undersigned understands that you, as Placement Agents, propose to enter into a Placement Agency Agreement (the “Placement Agency Agreement”) with Dyax Corp., a Delaware corporation (the “Company”), providing for the offering (the “Offering”) of 6,315,000 shares (the “Shares”) of common stock, par value $0.01 per share (the “Common Stock”), of the Company.  Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Placement Agency Agreement.

In consideration of the foregoing, and in order to induce you to act as Placement Agents in the offering, and for other good and valuable consideration receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of Deutsche Bank Securities Inc. and SG Cowen & Co., LLC, the undersigned will not, during the period beginning on the date of the final prospectus supplement relating to the Offering of the Shares and ending on the date 60 days after the date of such final prospectus supplement, (1) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (including without limitation, Common Stock which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued upon exercise of a stock option or warrant), or (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise.  In addition, the undersigned agrees that, without the prior written consent of Deutsche Bank Securities Inc. and SG Cowen & Co., LLC, it will not, during the period ending 60 days after the date of the Prospectus, make any demand for or exercise any right with respect to, the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock.

Notwithstanding the foregoing, the restrictions set forth in clause (1) and (2) above shall not apply to (a) transfers (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 Deutsche Bank Securities Inc. and SG Cowen & Co., LLC, or (iv) effected pursuant to any exchange of “underwater” options with the Company, (b) the acquisition or exercise of any stock option issued pursuant to the Company’s existing stock option plan, including any exercise effected by the delivery of Shares of the Company held by the undersigned, or (c) the purchase or sale of the Company’s securities pursuant to a plan, contract or instruction that satisfies all of the requirements of Rule 10b5-1(c)(1)(i)(B) that was in effect prior to the date hereof.  For purposes of this letter agreement, “immediate family” shall mean any relationship by blood, marriage or adoption, not more remote than first cousin.  None of the restrictions set forth in this letter agreement shall apply to Common Stock acquired in open market transactions.

In furtherance of the foregoing, the Company, and any duly appointed transfer agent for the registration or transfer of the securities described herein, are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this letter agreement.

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

The undersigned understands that, if the Placement Agency Agreement does not become effective, or if the Placement Agency Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Shares to be sold thereunder, the undersigned shall be released form all obligations under this letter agreement.

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This lock-up agreement shall be governed by and construed in accordance with the laws of the State of New York, without regard to the conflict of laws principles thereof.

Accepted as of the date
first set forth above:

DEUTSCHE BANK SECURITIES INC.

SG COWEN & CO., LLC

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