770,000 Shares NATUS MEDICAL INCORPORATED

Exhibit 1.01

770,000 Shares

NATUS MEDICAL INCORPORATED

Common Stock

PURCHASE AGREEMENT

April 4, 2008

ROTH CAPITAL PARTNERS, LLC

24 Corporate Plaza

Newport Beach, CA 92660

Ladies and Gentlemen:

Natus Medical Incorporated, a Delaware corporation (the “Company”) proposes, subject to the terms and conditions stated herein, to issue and sell to Roth Capital Partners, LLC (the “Underwriter”) an aggregate of 770,000 authorized but unissued shares (the “Securities”) of Common Stock, $.001 par value per share (the “Common Stock”), of the Company.

The Company and the Underwriter hereby confirm their agreement with respect to the purchase and sale of the Securities as follows:

1. Registration Statement and Prospectus. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) a registration statement on Form S-3 (File No. 333-133480) under the Securities Act of 1933, as amended (the “Securities Act”) and the rules and regulations (the “Rules and Regulations”) of the Commission thereunder, and such amendments to such registration statement as may have been required to the date of this Agreement. Such registration statement has been declared effective by the Commission. Such registration statement, at any given time, including amendments thereto to such time, the exhibits and any schedules thereto at such time, the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act at such time and the documents and information otherwise deemed to be a part thereof or included therein by Rule 430B under the Securities Act or otherwise pursuant to the Rules and Regulations at such time, is herein called the “Registration Statement.” The Registration Statement at the time it originally became effective is herein called the “Original Registration Statement.”

The Company is filing with the Commission pursuant to Rule 424 under the Securities Act a final prospectus supplement relating to the Securities to a form of prospectus included in the Registration Statement in the form heretofore delivered to the Underwriter. Such prospectus in the form in which it appears in the Registration Statement is hereinafter called the “Base Prospectus.” Such supplemental form of prospectus, in the form in which it shall be filed with the Commission pursuant to Rule 424(b) (including the Base Prospectus as so supplemented) is hereinafter called the “Prospectus.” Any reference herein to the Base Prospectus or the Prospectus shall be deemed to include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act as of the date of such prospectus.

For purposes of this Agreement, all references to the Registration Statement, the Base Prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval System (“EDGAR”). All references in this Agreement to amendments or supplements to the Registration Statement, the Base Prospectus or the Prospectus shall be deemed to mean and include the subsequent filing of any document under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) which is deemed to be incorporated therein by reference therein or otherwise deemed by the Rules and Regulations to be a part thereof.

2. Representations and Warranties of the Company.

(a) The Company represents and warrants to, and agrees with, the Underwriter as follows:

(i) No order preventing or suspending the use of any Prospectus has been issued by the Commission and each Prospectus, at the time of filing or the time of first use within the meaning of the Rules and Regulations, complied in all material respects with the requirements of the Securities Act and the Rules and Regulations and did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; except that the foregoing shall not apply to statements in or omissions from any Prospectus in reliance upon, and in conformity with, written information furnished to the Company by the Underwriter specifically for use in the preparation thereof.

(ii) The Company has complied to the Commission’s satisfaction with all requests of the Commission for additional or supplemental information. No stop order suspending the effectiveness of the Registration Statement is in effect and no proceedings for such purpose have been instituted or are pending or, to the best knowledge of the Company, are contemplated or threatened by the Commission.

(iii) Each part of the Registration Statement and any post-effective amendment thereto, at the time such part became effective (including each deemed effective date with respect to the Underwriter pursuant to Rule 430B under the Securities Act), at all other subsequent times until the expiration of the Prospectus Delivery Period (as defined below), and at the Closing Date (as hereinafter defined), and the Prospectus (or any amendment or supplement to the Prospectus), at the time of filing or the time of first use within the meaning of the Rules and Regulations, at all subsequent times until expiration of the Prospectus Delivery Period, and at the Closing Date complied and will comply in all material respects with the applicable requirements and provisions of the Securities Act, the Rules and Regulations and the Exchange Act and did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading. The

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Prospectus, as amended or supplemented, as of its date, or the time of first use within the meaning of the Rules and Regulations, at all subsequent times until the expiration of the Prospectus Delivery Period, and at the Closing Date, did not and will not contain 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. The representations and warranties set forth in the two immediately preceding sentences do not apply to statements in or omissions from the Registration Statement or any post-effective amendment thereto, or the Prospectus, or any amendments or supplements thereto, made in reliance upon and in conformity with written information furnished to the Company by the Underwriter, specifically for use in the preparation thereof.

(iv) Neither (A) the Issuer General Free Writing Prospectus(es) issued at or prior to the Time of Sale, the Statutory Prospectus and the information set forth in Schedule IV to this Agreement, all considered together (collectively, the “Time of Sale Disclosure Package”), nor (B) any individual Issuer Limited-Use Free Writing Prospectus, when considered together with the Time of Sale Disclosure Package, included as of the Time of Sale any untrue statement of a material fact or omitted as of the Time of Sale to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from any Statutory Prospectus included in the Registration Statement or any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by the Underwriter specifically for use therein. As used in this paragraph and elsewhere in this Agreement:

(1) “Time of Sale” means 7:00 pm (Eastern time) on the date of this Agreement.

(2) “Statutory Prospectus” as of any time means the Prospectus that is included in the Registration Statement immediately prior to that time. For purposes of this definition, information contained in a form of prospectus that is deemed retroactively to be a part of the Registration Statement pursuant to Rule 430B under the Securities Act shall be considered to be included in the Statutory Prospectus as of the actual time that form of prospectus is filed with the Commission pursuant to Rule 424(b) under the Securities Act.

(3) “Issuer Free Writing Prospectus” means any “issuer free writing prospectus,” as defined in Rule 433 under the Securities Act, relating to the Securities that (A) is required to be filed with the Commission by the Company, or (B) is exempt from filing pursuant to Rule 433(d)(5)(i) under the Securities Act because it contains a description of the Securities or of the offering that does not reflect the final terms, in each case in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g) under the Securities Act.

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(4) “Issuer General Free Writing Prospectus” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors, as evidenced by its being specified in Schedule I to this Agreement.

(5) “Issuer Limited-Use Free Writing Prospectus” means any Issuer Free Writing Prospectus that is not an Issuer General Free Writing Prospectus.

(v) (A) Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the Prospectus Delivery Period or until any earlier date that the Company notified or notifies the Underwriter as described in Section 4(a)(iii)(B), did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement, any Statutory Prospectus or the Prospectus. The foregoing sentence does not apply to statements in or omissions from any Issuer Free Writing Prospectus based upon and in conformity with written information furnished to the Company by the Underwriter specifically for use therein.

(B)(1) At the earliest time after the filing of the Registration Statement that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Securities Act) of the Securities and (2) at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405 under the Securities Act, including the Company or any subsidiary in the preceding three years not having been convicted of a felony or misdemeanor or having been made the subject of a judicial or administrative decree or order as described in Rule 405 (without taking account of any determination by the Commission pursuant to Rule 405 that it is not necessary that the Company be considered an ineligible issuer), nor an “excluded issuer” as defined in Rule 164 under the Securities Act.

(C) Each Issuer Free Writing Prospectus satisfied, as of its issue date and at all subsequent times through the Prospectus Delivery Period, all other conditions to use thereof as set forth in Rules 164 and 433 under the Securities Act.

(vi) The financial statements of the Company, together with the related notes, included or incorporated by reference in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus comply in all material respects with the requirements of the Securities Act and the Exchange Act and fairly present the financial condition of the Company as of the dates indicated and the results of operations and changes in cash flows for the periods therein specified in conformity with generally accepted accounting principles consistently applied throughout the periods involved; and the supporting schedules included in the Registration Statement present fairly the information required to be stated therein. No other financial statements or schedules are required to be included in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus. To the Company’s knowledge, Deloitte & Touche, LLP, which has expressed its opinion with respect to the financial statements and schedules filed as a part of the Registration Statement and included in the Registration Statement,

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the Time of Sale Disclosure Package and the Prospectus, is an independent public accounting firm within the meaning of the Securities Act and the Rules and Regulations and such accountants are not in violation of the auditor independence requirements of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act”).

(vii) Each of the Company and its subsidiaries has been duly organized and is validly existing as a corporation in good standing under the laws of its jurisdiction of incorporation. Each of the Company and its subsidiaries has the corporate power and authority to own its properties and conduct its business as currently being carried on and as described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, and is duly qualified to do business as a foreign corporation in good standing in each jurisdiction in which it owns or leases real property or in which the conduct of its business makes such qualification necessary and in which the failure to so qualify would have a material adverse effect upon the business, prospects, properties, operations, condition (financial or otherwise) or results of operations of the Company and its subsidiaries, taken as a whole, or in its ability to perform its obligations under this Agreement (“Material Adverse Effect”).

(viii) Except as contemplated in the Time of Sale Disclosure Package and in the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package, neither the Company nor any of its subsidiaries has incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, or declared or paid any dividends or made any distribution of any kind with respect to its capital stock; and there has not been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants or to the issuance of restricted stock under the Company’s existing stock awards plan), or any material change in the short-term or long-term debt, or any issuance of options, warrants, convertible securities or other rights to purchase the capital stock, of the Company or any of its subsidiaries (other than the issuance of options under the Company’s existing stock awards plans), or any material adverse change in the financial condition, business, prospects, property, operations or results of operations of the Company and its subsidiaries, taken as a whole (“Material Adverse Change”).

(ix) Except as set forth in the Time of Sale Disclosure Package and the Prospectus, there is not pending or, to the knowledge of the Company, threatened or contemplated, any action, suit or proceeding to which the Company or any of its subsidiaries is a party or of which any property or assets of the Company is the subject before or by any court or governmental agency, authority or body, or any arbitrator, which, individually or in the aggregate, might reasonably be expected to result in any Material Adverse Change.

(x) This Agreement has been duly authorized, executed and delivered by the Company, and constitutes a valid, legal and binding obligation of the Company, enforceable in accordance with its terms, except as rights to indemnity hereunder may be limited by federal or state securities laws and except as such enforceability may be limited by bankruptcy, insolvency, reorganization or similar laws affecting the rights of

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creditors generally and subject to general principles of equity. The execution, delivery and performance of this Agreement and the consummation of the transactions herein contemplated will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, any statute, any agreement or instrument to which the Company is a party or by which it is bound or to which any of its property is subject, or any order, rule, regulation or decree of any court or governmental agency or body having jurisdiction over the Company or any of its properties except for violations and defaults which individually or in the aggregate would not reasonably be expected to have a Material Adverse Effect. The execution, delivery and performance of this Agreement and the consummation of the transactions herein contemplated will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, the Company’s charter or by-laws. No consent, approval, authorization or order of, or filing with, any court or governmental agency or body is required for the execution, delivery and performance of this Agreement or for the consummation of the transactions contemplated hereby, including the issuance or sale of the Securities by the Company, except such as may be required under the Securities Act or state securities or blue sky laws; and the Company has the power and authority to enter into this Agreement and to authorize, issue and sell the Securities as contemplated by this Agreement.

(xi) All of the issued and outstanding shares of capital stock of the Company, including the outstanding shares of Common Stock, are duly authorized and validly issued, fully paid and nonassessable, have been issued in compliance with all federal and state securities laws, were not issued in violation of or subject to any preemptive rights or other rights to subscribe for or purchase securities that have not been waived in writing (a copy of which has been delivered to counsel to the Underwriter); the Securities which may be sold hereunder by the Company have been duly authorized and, when issued, delivered and paid for in accordance with the terms of this Agreement, will have been validly issued and will be fully paid and nonassessable; and the capital stock of the Company, including the Common Stock, conforms to the description thereof in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus. Except as otherwise stated in the Registration Statement, in the Time of Sale Disclosure Package or in the Prospectus, there are no preemptive rights or other rights to subscribe for or to purchase, or any restriction upon the voting or transfer of, any shares of Common Stock pursuant to the Company’s charter, by-laws or any agreement or other instrument to which the Company is a party or by which the Company is bound. Neither the filing of the Registration Statement nor the offering or sale of the Securities as contemplated by this Agreement gives rise to any rights for or relating to the registration of any shares of Common Stock or other securities of the Company that have not been waived. All of the issued and outstanding shares of capital stock of each of the Company’s subsidiaries have been duly and validly authorized and issued and are fully paid and nonassessable, and, except as otherwise described in the Registration Statement, in the Time of Sale Disclosure Package or in the Prospectus and except for any directors’ qualifying shares, the Company owns of record and beneficially, free and clear of any security interests, claims, liens, proxies, equities or other encumbrances, all of the issued and outstanding shares of such stock, except such as are described in the Registration Statement, in the Time of Sale Disclosure Package or in the Prospectus. Except as described in the Registration Statement, in the Time of Sale Disclosure Package or in the

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Prospectus, there are no options, warrants, agreements, contracts or other rights in existence to purchase or acquire from the Company or any subsidiary of the Company any shares of the capital stock of the Company or any subsidiary of the Company. The Company has an authorized and outstanding capitalization as set forth in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus (except as outstanding capitalization may have changed as a result of the exercise of stock options subsequent thereto).

(xii) The Company and each of its subsidiaries holds, and is operating in compliance in all material respects with, all franchises, grants, authorizations, licenses, permits, easements, consents, certificates and orders of any governmental or self-regulatory body required for the conduct of its business, and all such franchises, grants, authorizations, licenses, permits, easements, consents, certifications and orders are valid and in full force and effect in all material respects; and the Company and each of its subsidiaries is in compliance in all material respects with all applicable federal, state, local and foreign laws, regulations, orders and decrees.

(xiii) The Company and its subsidiaries have good and marketable title to all property (whether real or personal) described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus as being owned by them which are material to the business of the Company, in each case free and clear of all liens, claims, security interests, other encumbrances or defects except such as are described in the Registration Statement, in the Time of Sale Disclosure Package or in the Prospectus. The property held under lease by the Company and its subsidiaries is held by them under valid, subsisting and enforceable leases with only such exceptions with respect to any particular lease as do not interfere in any material respect with the conduct of the business of the Company or its subsidiaries.

(xiv) The Company and each of its subsidiaries owns or possesses or has valid right to use all patents, patent applications, trademarks, service marks, tradenames, trademark registrations, service mark registrations, copyrights, licenses, inventions, trade secrets and rights necessary for the conduct of the business of the Company and its subsidiaries as currently carried on and as described in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus; except as stated in the Registration Statement, in the Time of Sale Disclosure Package or in the Prospectus, to the knowledge of the Company, no name which the Company or any of its subsidiaries uses and no other aspect of the business of the Company or any of its subsidiaries will involve or give rise to any infringement of, or license or similar fees for, any patents, patent applications, trademarks, service marks, tradenames, trademark registrations, service mark registrations, copyrights, licenses, inventions, trade secrets or other similar rights of others material to the business or prospects of the Company and neither the Company nor any of its subsidiaries has received any notice alleging any such infringement or fee.

(xv) Neither the Company nor any of its subsidiaries is in violation of its respective charter or by-laws or in breach of or otherwise in default, and no event has occurred which, with notice or lapse of time or both, would constitute such a default, in

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the performance of any material obligation, agreement or condition contained in any bond, debenture, note, indenture, loan agreement or any other material contract, lease or other instrument to which it is subject or by which any of them may be bound, or to which any of the material property or assets of the Company or any of its subsidiaries is subject.

(xvi) The Company and its subsidiaries have timely filed all federal, state and local income tax returns required to be filed and are not in default in the payment of any taxes which were payable pursuant to said returns or any assessments with respect thereto, other than any which the Company or any of its subsidiaries is contesting in good faith.

(xvii) The Company has not distributed and will not distribute any prospectus or other offering material in connection with the offering and sale of the Securities other than any Preliminary Prospectus, the Time of Sale Disclosure Package or the Prospectus or other materials permitted by the Securities Act to be distributed by the Company; provided, however, that, except as set forth on Schedule I, the Company has not made and will not make any offer relating to the Securities that would constitute a “free writing prospectus” as defined in Rule 405 under the Securities Act, except in accordance with the provisions of Section 4(a)(xiv) of this Agreement.

(xviii) The Common Stock is registered pursuant to Section 12(b) of the Exchange Act and is included or approved for inclusion on the Nasdaq Global Market and the Company has taken no action designed to, or likely to have the effect of, terminating the registration of the Common Stock under the Exchange Act or delisting the Common Stock from the Nasdaq Global Market (although the Company may choose to list its securities on the NYSE) nor has the Company received any notification that the Commission or the Nasdaq Global Market is contemplating terminating such registration or listing. The Company has complied in all material respects with the applicable requirements of the Nasdaq Global Market for maintenance of inclusion of the Common Stock thereon. The Company has, to the extent required, filed an application to include the Securities on the Nasdaq Global Market.

(xix) Other than the subsidiaries of the Company listed on Schedule III hereto, the Company, directly or indirectly, owns no capital stock or other equity or ownership or proprietary interest in any corporation, partnership, association, trust or other entity.

(xx) The Company maintains a system of internal accounting controls sufficient to provide reasonable assurances that (A) transactions are executed in accordance with management’s general or specific authorization; (B) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain accountability for assets; (C) access to assets is permitted only in accordance with management’s general or specific authorization; and (D) the recorded accountability for assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as described in the Registration Statement, in the Time of Sale

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Disclosure Package or in the Prospectus, since December 31, 2007, there has been no change in the Company’s internal control over financial reporting that has materially affected, or is reasonably likely to materially affect, the Company’s internal control over financial reporting.

(xxi) Other than as contemplated by this Agreement, the Company has not incurred any liability for any finder’s or broker’s fee or agent’s commission in connection with the execution and delivery of this Agreement or the consummation of the transactions contemplated hereby.

(xxii) The Company carries, or is covered by, insurance in such amounts and covering such risks as is adequate for the conduct of its business and the value of its properties and as is customary for companies engaged in similar businesses in similar industries.

(xxiii) The Company is not and, after giving effect to the offering and sale of the Securities, will not be an “investment company,” as such term is defined in the Investment Company Act of 1940, as amended.

(xxiv) The conditions for use of Form S-3, set forth in the General Instructions thereto, have been satisfied. The Company also complies with the standards for using Form S-3 as in place prior to October 21, 1992, namely, as of a date within 30 days prior to the date of this Agreement, the aggregate market value of the voting and non-voting common equity of the Company held by non-affiliates of the Company exceeded $150,000,000 (as calculated by reference to the closing price of the Common Stock on the Nasdaq Global Market) and non-affiliates of the Company held more than 3,000,000 shares of the Common Stock on such date.

(xxv) The documents incorporated by reference in the Time of Sale Disclosure Package, the Registration Statement and in the Prospectus, when they became effective or were filed with the Commission, as the case may be, conformed in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, and were filed on a timely basis with the Commission and none of such documents contained an untrue statement of a material fact or omitted to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; any further documents so filed and incorporated by reference in the Time of Sale Disclosure Package, the Registration Statement or in the Prospectus, when such documents are filed with the Commission, will conform in all material respects to the requirements of the Exchange Act, and will not contain an untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(xxvi) The Company is in substantial compliance with all applicable provisions of the Sarbanes-Oxley Act and the rules and regulations of the Commission thereunder that are effective with respect to the Company and its subsidiaries on the date

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of this Agreement, except where such noncompliance would not have, individually or in the aggregate, a Material Adverse Effect.

(xxvii) The Company has established and maintains disclosure controls and procedures (as defined in Rules 13a-14 and 15d-14 under the Exchange Act) and such controls and procedures are effective in ensuring that material information relating to the Company, including its subsidiaries, is made known to the principal executive officer and the principal financial officer. The Company has utilized such controls and procedures in preparing and evaluating the disclosures in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus.

(b) Any certificate signed by any officer of the Company and delivered to the Underwriter or to the Underwriter’s Counsel shall be deemed a representation and warranty by the Company to the Underwriter as to the matters covered thereby.

3. Purchase, Sale and Delivery of Securities.

(a) On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Company agrees to issue and sell the Securities to the Underwriter, and the Underwriter agrees to purchase from the Company the Securities as set forth opposite the name of such Underwriter below on the signature page hereof. The purchase price for each share of the Securities shall be $18.27 per share. The Company agrees to pay the Underwriter’s compensation as set forth in Schedule IV hereto.

In addition, the Company hereby grants to the Underwriter the option to purchase an aggregate of up to 15% of the Securities purchased pursuant to this Agreement and, upon the basis of the warranties and representations and subject to the terms and conditions herein set forth, the Underwriter shall have the right to purchase, from the Company (subject to such adjustment as you shall determine to avoid fractional shares), all or a portion of additional shares (“Additional Shares”) as may be necessary to cover over-allotments made in connection with the offering of the Securities, at the same purchase price per share to be paid by the Underwriter to the Company for the Securities. This option may be exercised by you at any time (but not more than once) on or before the thirtieth day following the date hereof, by written notice to the Company. Such notice shall set forth the aggregate number of Additional Shares as to which the option is being exercised, and the date and time when the Additional Shares are to be delivered (such date and time being herein referred to as the “Option Closing Date”); provided, however, that the Option Closing Date shall not be earlier than the Closing Date (as defined below) nor earlier than the second business day after the date on which the option shall have been exercised nor later than the fifth business day after the date on which the option shall have been exercised unless the Company and you otherwise agree.

Payment of the purchase price and delivery for the Additional Shares shall be made at the Option Closing Date in the same manner and at the same office as the payment for the Securities as set forth in subparagraph (b) below. For the purpose of expediting the checking of the certificate for the Additional Shares by you, the Company agrees to make a form of such certificate available to you for such purpose at least one full business day preceding the Option Closing Date.

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(b) The Securities will be delivered by the Company to the Underwriter against payment of the purchase price therefor by wire transfer of same day funds payable to the order of the Company, as appropriate, at the offices of Roth Capital Partners, LLC, 24 Corporate Plaza, Newport Beach, CA 92660, or such other location as may be mutually acceptable, at 9:00 a.m. PST or Central time, respectively, on the third (or if the Securities are priced, as contemplated by Rule 15c6-1(c) under the Exchange Act, after 4:30 p.m. Eastern time, the fourth) full business day following the date hereof, or at such other time and date as the Underwriter and the Company determine pursuant to Rule 15c6-1(a) under the Exchange Act, such time and date of delivery being herein referred to as the “Closing Date.” If the Underwriter so elects, delivery of the Securities may be made by credit through full fast transfer to the account at The Depository Trust Company designated by the Underwriter. Certificates representing the Securities, in definitive form and in such denominations and registered in such names as the Underwriter may request upon at least two business days’ prior notice to the Company, will be made available for checking and packaging not later than 10:30 a.m., PST or Central time, as applicable, on the business day next preceding the Closing Date at the above addresses, or such other location as may be mutually acceptable.

4. Covenants.

(a) The Company covenants and agrees with the Underwriter as follows:

(i) During the period beginning on the date hereof and ending on the later of the Closing Date or such date, as in the opinion of counsel for the Underwriter, the Prospectus is no longer required by law to be delivered (or in lieu thereof the notice referred to in Rule 173(a) under the Securities Act is no longer required to be provided), in connection with sales by an underwriter or dealer (the “Prospectus Delivery Period”), prior to amending or supplementing the Registration Statement, the Time of Sale Disclosure Package or the Prospectus, the Company shall furnish to the Underwriter for review a copy of each such proposed amendment or supplement, and the Company shall not file any such proposed amendment or supplement to which the Underwriter reasonably object.

(ii) After the date of this Agreement, the Company shall promptly advise the Underwriter in writing (i) of the receipt of any comments of, or requests for additional or supplemental information from, the Commission, (ii) of the time and date of any filing of any post-effective amendment to the Registration Statement or any amendment or supplement to any Prospectus, the Time of Sale Disclosure Package or the Prospectus, (iii) of the time and date that any post-effective amendment to the Registration Statement becomes effective and (iv) of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or any post-effective amendment thereto or of any order preventing or suspending its use or the use of any Prospectus, the Time of Sale Disclosure Package, the Prospectus or any Issuer Free Writing Prospectus, or of any proceedings to remove, suspend or terminate from listing or quotation the Common Stock from any securities exchange upon which it is

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listed for trading or included or designated for quotation, or of the threatening or initiation of any proceedings for any of such purposes. If the Commission shall enter any such stop order at any time, the Company will use its reasonable efforts to obtain the lifting of such order at the earliest possible moment. Additionally, the Company agrees that it shall comply with the provisions of Rules 424(b), 430A and 430B, as applicable, under the Securities Act and will use its reasonable efforts to confirm that any filings made by the Company under Rule 424(b) or Rule 433 were received in a timely manner by the Commission (without reliance on Rule 424(b)(8) or Rule 164(b)).

(iii) (A) During the Prospectus Delivery Period, the Company will comply as far as it is able with all requirements imposed upon it by the Securities Act, as now and hereafter amended, and by the Rules and Regulations, as from time to time in force, and by the Exchange Act so far as necessary to permit the continuance of sales of or dealings in the Securities as contemplated by the provisions hereof, the Time of Sale Disclosure Package, and the Registration Statement and the Prospectus. If during such period any event occurs as a result of which the Prospectus (or if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package ) would include an untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances then existing, not misleading, or if during such period it is necessary or appropriate in the opinion of the Company or its counsel or the Underwriter or counsel to the Underwriter to amend the Registration Statement or supplement the Prospectus (or if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package ) to comply with the Securities Act or to file under the Exchange Act any document which would be deemed to be incorporated by reference in the Prospectus in order to comply with the Securities Act or the Exchange Act, the Company will promptly notify the Underwriter and will amend the Registration Statement or supplement the Prospectus (or if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) or file such document (at the expense of the Company) so as to correct such statement or omission or effect such compliance.

(B) If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information contained in the Registration Statement, the Statutory Prospectus or the Prospectus or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at that subsequent time, not misleading, the Company has promptly notified or promptly will notify the Underwriter and has promptly amended or will promptly amend or supplement, at its own expense, such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission.

(iv) The Company shall take or cause to be taken all necessary action to qualify the Securities for sale under the securities laws of such jurisdictions as the Underwriter reasonably designates and to continue such qualifications in effect so long as required for the distribution of the Securities, except that the Company shall not be required in connection therewith to qualify as a foreign corporation or to execute a general consent to service of process in any state.

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(v) The Company will furnish to the Underwriter and counsel for the Underwriter copies of the Registration Statement, the Prospectus, any Issuer Free Writing Prospectus, and all amendments and supplements to such documents, in each case as soon as available and in such quantities as the Underwriter may from time to time reasonably request.

(vi) The Company will make generally available to its security holders as soon as practicable, but in any event not later than 15 months after the end of the Company’s current fiscal quarter, an earnings statement (which need not be audited) covering a 12-month period that shall satisfy the provisions of Section 11(a) of the Securities Act and Rule 158 of the Rules and Regulations.

(vii) The Company, whether or not the transactions contemplated hereunder are consummated or this Agreement is terminated, will pay or cause to be paid (A) all expenses (including transfer taxes allocated to the respective transferees) incurred in connection with the delivery to the Underwriter of the Securities, (B) all expenses and fees (including, without limitation, fees and expenses of the Company’s counsel) in connection with the preparation, printing, filing, delivery, and shipping of the Registration Statement (including the financial statements therein and all amendments, schedules, and exhibits thereto), the Securities, the Prospectus, any Issuer Free Writing Prospectus and any amendment thereof or supplement thereto, and the printing, delivery, and shipping of this Agreement and other underwriting documents, including Blue Sky Memoranda (covering the states and other applicable jurisdictions), (C) all filing fees and fees and disbursements of the Underwriter’s counsel incurred in connection with the qualification of the Securities for offering and sale by the Underwriter or by dealers under the securities or blue sky laws of the states and other jurisdictions which the Underwriter shall designate, (D) the fees and expenses of any transfer agent or registrar, (E) the filing fees and fees and disbursements of Underwriter’s counsel incident to any required review and approval by the Financial Industry Regulatory Authority (“FINRA”) of the terms of the sale of the Securities, (F) listing fees, if any, and (G) all other costs and expenses incident to the performance of its obligations hereunder that are not otherwise specifically provided for herein. If this Agreement is terminated by the Underwriter pursuant to Section 8(i), (ii) or (iii) hereof or if the sale of the Securities provided for herein is not consummated by reason of any failure, refusal or inability on the part of the Company to perform any, agreement on its part to be performed, or because any other condition of the Underwriter’s obligations hereunder required to be fulfilled by the Company is not fulfilled, the Company will reimburse the Underwriter for all out-of-pocket disbursements (including but not limited to fees and disbursements of counsel, printing expenses, travel expenses, postage, facsimile and telephone charges) incurred by the Underwriter in connection with their investigation, preparing to market and marketing the Securities or in contemplation of performing their obligations hereunder. Notwithstanding anything contained herein, the maximum amount payable by the Company for Underwriter’s counsel fees, disbursements and expenses pursuant to this Section 4(a)(vii) shall be $50,000.

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(viii) The Company will apply the net proceeds from the sale of the Securities to be sold by it hereunder for the purposes set forth in the Time of Sale Disclosure Package and in the Prospectus.

(ix) The Company has not taken and will not take, directly or indirectly, any action designed to or which might reasonably be expected to cause or result in, or which has constituted, the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities

(x) The Company will not incur any liability for any finder’s or broker’s fee or agent’s commission in connection with the execution and delivery of this Agreement or the consummation of the transactions contemplated hereby.

(xi) During the Prospectus Delivery Period, the Company will file on a timely basis with the Commission such periodic and special reports as required by the Rules and Regulations.

(xii) The Company and its subsidiaries will maintain such controls and other procedures, including without limitation those applicable to the Company and required by Sections 302 and 906 of the Sarbanes-Oxley Act and the applicable regulations thereunder, that are designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, including without limitation, controls and procedures designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the Company’s management, including its principal executive officer and its principal financial officer, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure, to ensure that material information relating to Company, including its subsidiaries, is made known to them by others within those entities.

(xiii) The Company and its subsidiaries will substantially comply with all effective applicable provisions of the Sarbanes-Oxley Act.

(xiv) The Company represents and agrees that, unless it obtains the prior written consent of the Underwriter, and the Underwriter represents and agrees that, unless it obtains the prior written consent of the Company, it has not made and will not make any offer relating to the Securities that would constitute an “issuer free writing prospectus,” as defined in Rule 433 under the Securities Act, or that would otherwise constitute a “free writing prospectus,” as defined in Rule 405 under the Securities Act, required to be filed with the Commission; provided that the prior written consent of the parties hereto shall be deemed to have been given in respect of the free writing prospectuses included in Schedule I. Any such free writing prospectus consented to by the Company and the Underwriter is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company represents that it has treated or agrees that it will treat each Permitted Free Writing Prospectus as an “issuer free writing prospectus,” as defined in Rule 433, and has complied and will comply with the requirements of Rule 433 applicable to any Permitted Free Writing Prospectus, including timely Commission filing where required, legending and record keeping.

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5. Conditions of the Underwriter’s Obligations. The obligations of the Underwriter hereunder are subject to the accuracy, as of the date hereof and at the Closing Date (as if made at the Closing Date), of and compliance with all representations, warranties and agreements of the Company contained herein, to the performance by the Company of its obligations hereunder and to the following additional conditions:

(a) If filing of the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus, is required under the Securities Act or the Rules and Regulations, the Company shall have filed the Prospectus (or such amendment or supplement) or such Issuer Free Writing Prospectus with the Commission in the manner and within the time period so required (without reliance on Rule 424(b)(8) or Rule 164(b)); the Registration Statement shall remain effective; no stop order suspending the effectiveness of the Registration Statement or any part thereof, or any amendment thereof, nor suspending or preventing the use of the Time of Sale Disclosure Package, the Prospectus or any Issuer Free Writing Prospectus shall have been issued; no proceedings for the issuance of such an order shall have been initiated or threatened; any request of the Commission for additional information (to be included in the Registration Statement, the Time of Sale Disclosure Package, the Prospectus, any Issuer Free Writing Prospectus or otherwise) shall have been complied with to the Underwriter’s satisfaction; and the FINRA shall have raised no objection to the fairness and reasonableness of the underwriting terms and arrangements.

(b) The Underwriter shall not have reasonably determined, and advised the Company, that the Registration Statement, the Time of Sale Disclosure Package or the Prospectus, or any amendment thereof or supplement thereto, or any Issuer Free Writing Prospectus, contains an untrue statement of fact which, in the Underwriter’s reasonable opinion, is material, or omits to state a fact which, in the Underwriter’s reasonable opinion, is material and is required to be stated therein or necessary to make the statements therein not misleading.

(c) Except as contemplated in the Time of Sale Disclosure Package or in the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package, neither the Company nor any of its subsidiaries shall have incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, or declared or paid any dividends or made any distribution of any kind with respect to its capital stock; and there shall not have been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants), or any material change in the short-term or long-term debt of the Company, or any issuance of options, warrants, convertible securities or other rights to purchase the capital stock of the Company or any of its subsidiaries, or any Material Adverse Change (whether or not arising in the ordinary course of business), or any loss by strike, fire, flood, earthquake, accident or other calamity, whether or not covered by insurance, incurred by the Company or any subsidiary, the effect of which, in any such case described above, in the Underwriter’s judgment, makes it impractical or inadvisable to offer or deliver the Securities on the terms and in the manner contemplated in the Time of Sale Disclosure Package, the Registration Statement and in the Prospectus.

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(d) On or after the Time of Sale (i) no downgrading shall have occurred in the rating accorded any of the Company’s securities by any “nationally recognized statistical organization,” as that term is defined by the Commission for purposes of Rule 436(g)(2) under the Securities Act, and (ii) no such organization shall have publicly announced that it has under surveillance or review, with possible negative implications, its rating of any of the Company’s securities.

(e) On the Closing Date, there shall have been furnished to the Underwriter the opinion of Fenwick & West LLP, counsel for the Company, dated the Closing Date and addressed to the Underwriter, in form and substance reasonably satisfactory to the Underwriter, to the effect set forth in Schedule II.

In rendering such opinion such counsel may rely (i) as to matters of law other than California, Delaware and federal law, upon the opinion or opinions of local counsel provided that the extent of such reliance is specified in such opinion and that such counsel shall state that such opinion or opinions of local counsel are satisfactory to them and that they believe they and the Underwriter are justified in relying thereon and (ii) as to matters of fact, to the extent such counsel deems reasonable upon certificates of officers of the Company and its subsidiaries provided that the extent of such reliance is specified in such opinion.

(f) On the Closing Date, the Underwriter shall have received a letter of Deloitte & Touche LLP, dated the Closing Date and addressed to the Underwriter, confirming that they are independent public accountants within the meaning of the Securities Act and are in compliance with the applicable requirements relating to the qualifications of accountants under Rule 2-01 of Regulation S-X of the Commission, and stating, as of the date of such letter (or, with respect to matters involving changes or developments since the respective dates as of which specified financial information is given in the Time of Sale Disclosure Package, as of a date not prior to the date hereof or more than five days prior to the date of such letter), the conclusions and findings of said firm with respect to the financial information and other matters typically covered by “comfort letters” delivered by accountants in connection with the type of transaction contemplated by this Agreement.

(g) On the Closing Date, there shall have been furnished to the Underwriter a certificate, dated the Closing Date and addressed to the Underwriter, signed by the chief executive officer or the chief financial officer of the Company, in their capacity as officers of the Company, to the effect that:

(i) The representations and warranties of the Company in this Agreement are true and correct, in all material respects, as if made at and as of the Closing Date, and the Company has complied with all the agreements and satisfied all the conditions on its part to be performed or satisfied at or prior to the Closing Date;

(ii) No stop order or other order suspending the effectiveness of the Registration Statement or any part thereof or any amendment thereof or the qualification

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of the Securities for offering or sale nor suspending or preventing the use of the Time of Sale Disclosure Package, the Prospectus or any Issuer Free Writing Prospectus, has been issued, and no proceeding for that purpose has been instituted or, to the best of their knowledge, is contemplated by the Commission or any state or regulatory body; and

(iii) The signers of said certificate have carefully examined the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, and any amendments thereof or supplements thereto (including any documents filed under the Exchange Act and deemed to be incorporated by reference into the Time of Sale Disclosure Package, the Registration Statement or the Prospectus), and

(A) each part of the Registration Statement and the Prospectus, and any amendments thereof or supplements thereto (including any documents filed under the Exchange Act and deemed to be incorporated by reference into the Prospectus) contain, and contained, when such part of the Registration Statement (or such amendment) became effective, all statements and information required to be included therein, each part of the Registration Statement, or any amendment thereof, does not contain, and did not contain, when such part of the Registration Statement (or such amendment) became effective, any untrue statement of a material fact or omit to state, and did not omit to state when such part of the Registration Statement (or such amendment) became effective, any material fact required to be stated therein or necessary to make the statements therein not misleading, and the Prospectus, as amended or supplemented, does not include and did not include as of its date, or the time of first use within the meaning of the Rules and Regulations, any untrue statement of a material fact or omit to state and did not omit to state as of its date, or the time of first use within the meaning of the Rules and Regulations, a material fact necessary to make the statements therein, in light of the circumstances under which they were made,

(B) neither (1) the Time of Sale Disclosure Package nor (2) any individual Issuer Limited-Use Free Writing Prospectus, when considered together with the Time of Sale Disclosure Package, include, nor included as of the Time of Sale any untrue statement of a material fact or omits, or omitted as of the Time of Sale, to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(C) since the Time of Sale, there has occurred no event required to be set forth in an amended or supplemented prospectus which has not been so set forth, and no event which has required that there be filed under the Exchange Act any report that upon such filing would be deemed to be incorporated by reference into the Time of Sale Disclosure Package, the Registration Statement or into the Prospectus that has not been so filed,

(D) subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package, neither the Company nor any of its subsidiaries has incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, not in the ordinary course of

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business, or declared or paid any dividends or made any distribution of any kind with respect to its capital stock, and except as disclosed in the Time of Sale Disclosure Package or in the Prospectus, there has not been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants), or any material change in the short-term or long-term debt, or any issuance of options, warrants, convertible securities or other rights to purchase the capital stock, of the Company, or any of its subsidiaries, or any Material Adverse Change or any development involving a prospective Material Adverse Change (whether or not arising in the ordinary course of business), or any loss by strike, fire, flood, earthquake, accident or other calamity, whether or not covered by insurance, incurred by the Company or any subsidiary, and

(E) except as stated in the Time of Sale Disclosure Package or in the Prospectus, there is not pending, or, to the knowledge of the Company, threatened or contemplated, any action, suit or proceeding to which the Company or any of its subsidiaries is a party before or by any court or governmental agency, authority or body, or any arbitrator, which could reasonably be expected to result in any Material Adverse Change.

(h) The Company shall have furnished to the Underwriter and counsel for the Underwriter such additional documents, certificates and evidence as the Underwriter or counsel for the Underwriter may have reasonably requested.

All such opinions, certificates, letters and other documents will be in compliance with the provisions hereof only if they are satisfactory in form and substance to the Underwriter and counsel for the Underwriter. The Company will furnish the Underwriter with such conformed copies of such opinions, certificates, letters and other documents as the Underwriter shall reasonably request.

6. Indemnification and Contribution.

(a) The Company agrees to indemnify and hold harmless the Underwriter against any losses, claims, damages or liabilities to which the Underwriter may become subject, under the Securities Act or otherwise (including in settlement of any litigation if such settlement is effected with the written consent of the Company), insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon (i) an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, including the information deemed to be a part of the Registration Statement at the time of effectiveness and at any subsequent time pursuant to Rules 430A and 430B of the Rules and Regulations, the Time of Sale Disclosure Package, the Prospectus, or any amendment or supplement thereto (including any documents filed under the Exchange Act and deemed to be incorporated by reference into the Prospectus), any Issuer Free Writing Prospectus or in any materials or information provided to investors by, or with the approval of, the Company in connection with the marketing of the offering of the Common Stock (“Marketing Materials”), including any roadshow or investor presentations made to investors by the Company (whether in person or electronically) or arise out of or are based upon the omission or alleged omission to state therein a material fact required

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to be stated therein or necessary to make the statements therein not misleading, and will reimburse the Underwriter for any legal or other expenses reasonably incurred by it in connection with investigating or defending against such loss, claim, damage, liability or action; or (ii) in whole or in part upon any inaccuracy in the representations and warranties of the Company contained herein; or (iii) in whole or in part upon any failure of the Company to perform its obligations hereunder or under law; provided, however, that the Company shall not be liable in any such case to the extent that any such loss, claim, damage, liability or action arises out of or is based upon an untrue statement or alleged untrue statement or omission or alleged omission made in the Registration Statement, any Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, or any such amendment or supplement, any Issuer Free Writing Prospectus or in any Marketing Materials, in reliance upon and in conformity with written information furnished to the Company by the Underwriter specifically for use in the preparation thereof.

The Company agrees that, as an interim measure during the pendency of any claim, action, investigation, inquiry or other proceeding arising out of or based upon any statement or omission, or any alleged statement or omission, described in this Section 6(a), it will reimburse the Underwriter on a monthly basis for all reasonable legal fees or other expenses incurred in connection with investigating or defending any such claim, action, investigation, inquiry or other proceeding, notwithstanding the absence of a judicial determination as to the propriety and enforceability of the Company’s obligation to reimburse the Underwriter for such expenses and the possibility that such payments might later be held to have been improper by a court of competent jurisdiction. To the extent that any such interim reimbursement payment is so held to have been improper, the Underwriter shall promptly return it to the Company, together with interest, compounded daily, determined on the basis of the prime rate (or other commercial lending rate for borrowers of the highest credit standing) announced from time to time by Wells Fargo Bank, N.A. (the “Prime Rate”). Any such interim reimbursement payments which are not made to the Underwriter within 30 days of a written request for reimbursement shall bear interest at the Prime Rate from the date of such request. This indemnity agreement shall be in addition to any liabilities which the may otherwise have.

(b) The Underwriter will indemnify and hold harmless the Company against any losses, claims, damages or liabilities to which the Company may become subject, under the Securities Act or otherwise (including in settlement of any litigation, if such settlement is effected with the written consent of such Underwriter), insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, the Time of Sale Disclosure Package, the Prospectus, or any amendment or supplement thereto any Issuer Free Writing Prospectus or any marketing materials, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in the Registration Statement, the Time of Sale Disclosure Package, the Prospectus, or any amendment or supplement thereto, or any Issuer Free Writing Prospectus or any marketing materials in reliance upon and in conformity with written information furnished to the Company by the Underwriter specifically for use in the preparation thereof, and will reimburse the Company for any legal or other expenses reasonably incurred by the Company in connection with investigating or defending against any such loss, claim, damage, liability or action.

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The Company agrees that, as an interim measure during the pendency of any claim, action, investigation, inquiry or other proceeding arising out of or based upon any statement or omission, or any alleged statement or omission, described in this Section 6(b), it will reimburse the Underwriter on a monthly basis for all reasonable legal fees or other expenses incurred in connection with investigating or defending any such claim, action, investigation, inquiry or other proceeding, notwithstanding the absence of a judicial determination as to the propriety and enforceability of the Company’s obligation to reimburse the Underwriter for such expenses and the possibility that such payments might later be held to have been improper by a court of competent jurisdiction. To the extent that any such interim reimbursement payment is so held to have been improper, the Underwriter shall promptly return it to the Company, together with interest, compounded daily, determined on the basis of the prime rate (or other commercial lending rate for borrowers of the highest credit standing) announced from time to time by Wells Fargo Bank, N.A. (the “Prime Rate”). Any such interim reimbursement payments which are not made to the Underwriter within 30 days of a written request for reimbursement shall bear interest at the Prime Rate from the date of such request. This indemnity agreement shall be in addition to any liabilities which the may otherwise have.

(c) Promptly after receipt by an indemnified party under subsection (a) or (b) above of notice of the commencement of any action, such indemnified party shall, if a claim in respect thereof is to be made against the indemnifying party under such subsection, notify the indemnifying party in writing of the commencement thereof; but the omission so to notify the indemnifying party shall not relieve the indemnifying party from any liability that it may have to any indemnified party except to the extent such indemnifying party has been materially prejudiced by such failure. In case any such action shall be brought against any indemnified party, and it shall notify the indemnifying party of the commencement thereof, the indemnifying party shall be entitled to participate in, and, to the extent that it shall wish, jointly with any other indemnifying party similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party, and after notice from the indemnifying party to such indemnified party of the indemnifying party’s election so to assume the defense thereof, the indemnifying party shall not be liable to such indemnified party under such subsection for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof other than reasonable costs of investigation; provided, however, that if (i) the indemnified party has reasonably concluded (based on advice of counsel) that there may be legal defenses available to it or other indemnified parties that are different from or in addition to those available to the indemnifying party, (ii) or a conflict or potential conflict exists (based on advice of counsel to the indemnified party) between the indemnified party and the indemnifying party (in which case the indemnifying party will not have the right to direct the defense of such action on behalf of the indemnified party), or (iii) the indemnifying party has not in fact employed counsel reasonably satisfactory to the indemnified party to assume the defense of such action with a reasonable time after receiving notice of the commencement of the action, the indemnified party shall have the right to employ a single counsel to represent it in any claim in respect of which indemnity may be sought under subsection (a) or (b) of this Section 6, in which event the reasonable fees and expenses of such separate counsel shall be borne by the indemnifying party or parties and reimbursed to the indemnified party as incurred (in accordance with the provisions of the second paragraph in subsection (a) above).

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The indemnifying party under this Section 6 shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the indemnifying party agrees to indemnify the indemnified party against any loss, claim, damage, liability or expense by reason of such settlement or judgment. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement, compromise or consent to the entry of judgment in any pending or threatened action, suit or proceeding in respect of which any indemnified party is or could have been a party and indemnity was or could have been sought hereunder by such indemnified party, unless such settlement, compromise or consent (a) includes an unconditional release of such indemnified party from all liability on claims that are the subject matter of such action, suit or proceeding and (b) does not include a statement as to or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party.

(d) If the indemnification provided for in this Section 6 is unavailable or insufficient to hold harmless an indemnified party under subsection (a) or (b) above, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party as a result of the losses, claims, damages or liabilities referred to in subsection (a) or (b) above, (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriter on the other from the offering of the Securities or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company on the one hand and the Underwriter 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 Underwriter on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company bear to the total underwriting discounts and commissions received by the Underwriter, in each case as set forth in the table on the cover page of the Prospectus. The relative fault shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or the Underwriter and the parties’ relevant intent, knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The Company and the Underwriter agree that it would not be just and equitable if contributions pursuant to this subsection (d) were to be determined by pro rata allocation or by any other method of allocation which does not take account of the equitable considerations referred to in the first sentence of this subsection (d). The amount paid by an indemnified party as a result of the losses, claims, damages or liabilities referred to in the first sentence of this subsection (d) shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending against any action or claim which is the subject of this subsection (d). Notwithstanding the provisions of this subsection (d), the Underwriter shall not be required to contribute any amount in excess of the amount by which the total price at which the Securities were offered to the public exceeds the amount of any damages that the Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

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(e) The obligations of the Company under this Section 6 shall be in addition to any liability which the Company may otherwise have and the benefits of such obligations shall extend, upon the same terms and conditions, to each person, if any, who controls the Underwriter within the meaning of the Securities Act; and the obligations of the Underwriter under this Section 6 shall be in addition to any liability that the Underwriter may otherwise have and the benefits of such obligations shall extend, upon the same terms and conditions, to each director of the Company (including any person who, with his consent, is named in the Registration Statement as about to become a director of the Company), to each officer of the Company who has signed the Registration Statement and to each person, if any, who controls the Company within the meaning of the Securities Act.

(f) The Underwriter confirms and the Company acknowledges that there is no information concerning the Underwriter furnished in writing to the Company by the Underwriter specifically for inclusion in the Registration Statement, the Time of Sale Disclosure Package, the Prospectus or any Issuer Free Writing Prospectus.

7. Representations and Agreements to Survive Delivery. All representations, warranties, and agreements of the Company herein or in certificates delivered pursuant hereto, including but not limited to the agreements of the Underwriter and the Company contained in Section 6 hereof, shall remain operative and in full force and effect regardless of any investigation made by or on behalf of the Underwriter or any controlling person thereof, or the Company or any of its officers, directors, or controlling persons, and shall survive delivery of, and payment for, the Securities to and by the Underwriter hereunder.

8. Termination of this Agreement.

(a) The Underwriter shall have the right to terminate this Agreement by giving notice to the Company as hereinafter specified at any time at or prior to the Closing Date, if (i) the Company shall have failed, refused or been unable, at or prior to the Closing Date, to perform any material agreement on its part to be performed hereunder, (ii) any condition of the Underwriter’s obligations hereunder is not fulfilled, (iii) trading in the Company’s Common Stock shall have been suspended by the Commission or the American Stock Exchange or trading in securities generally on the Nasdaq Global Market, New York Stock Exchange or the American Stock Exchange shall have been suspended, (iv) minimum or maximum prices for trading shall have been fixed, or maximum ranges for prices for securities shall have been required, on the Nasdaq Global Market, New York Stock Exchange or the American Stock Exchange, by such Exchange or by order of the Commission or any other governmental authority having jurisdiction, (v) a banking moratorium shall have been declared by federal or California or New York state authorities, or (vi) there shall have occurred any attack on, outbreak or escalation of hostilities or act of terrorism involving the United States, any declaration by the United States of a national emergency or war, any change in financial markets, any substantial change or development involving a prospective substantial change in United States or international political, financial or economic conditions, or any other calamity or crisis that, in the Underwriter’s judgment, is material and adverse and makes it impractical or inadvisable to

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proceed with the completion of the sale of and payment for the Securities. Any such termination shall be without liability of any party to any other party except that the provisions of Section 4(a)(vii) and Section 6 hereof shall at all times be effective and shall survive such termination.

(b) If the Underwriter elects to terminate this Agreement as provided in this Section, the Company shall be notified promptly by the Underwriter by telephone, confirmed by letter.

9. Default the Company. If the Company shall fail at the Closing Date to sell and deliver the Securities which it is obligated to sell hereunder, then this Agreement shall terminate without any liability on the part of the Underwriter or, except as provided in Section 4(a)(vii), any non-defaulting party. No action taken pursuant to this Section shall relieve the Company from liability, if any, in respect of such default.

10. Notices. Except as otherwise provided herein, all communications hereunder shall be in writing and, if to the Underwriter, shall be mailed, delivered or telecopied to Roth Capital Partners, LLC, 24 Corporate Plaza, Newport Beach, CA 92660, Attn: Aaron Gurewitz; if to the Company, shall be mailed, delivered or telecopied to it at 1501 Industrial Road, San Carlos, California 94070, Attention: James B. Hawkins; or in each case to such other address as the person to be notified may have requested in writing. Any party to this Agreement may change such address for notices by sending to the parties to this Agreement written notice of a new address for such purpose.

11. Persons Entitled to Benefit of Agreement. This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and assigns and the controlling persons, officers and directors referred to in Section 6. Nothing in this Agreement is intended or shall be construed to give to any other person, firm or corporation any legal or equitable remedy or claim under or in respect of this Agreement or any provision herein contained. The term “successors and assigns” as herein used shall not include any purchaser, as such purchaser, of any of the Securities from the Underwriter.

12. Absence of Fiduciary Relationship. The Company acknowledges and agrees that: (a) the Underwriter has been retained solely to act as underwriter in connection with the sale of the Securities and that no fiduciary, advisory or agency relationship between the Company and the Underwriter has been created in respect of any of the transactions contemplated by this Agreement, irrespective of whether the Underwriter has advised or is advising the Company on other matters; (b) the price and other terms of the Securities set forth in this Agreement were established by the Company following discussions and arms-length negotiations with the Underwriter and the Company is capable of evaluating and understanding and understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement; (c) it has been advised that the Underwriter and its affiliates are engaged in a broad range of transactions which may involve interests that differ from those of the Company and that the Underwriter has no obligation to disclose such interest and transactions to the Company by virtue of any fiduciary, advisory or agency relationship; (d) it has been advised that the Underwriter is acting, in respect of the transactions contemplated by this Agreement, solely for the benefit of the Underwriter, and not on behalf of the Company.

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13. Governing Law. This Agreement shall be governed by and construed in accordance with the laws of the State of California.

14. Counterparts. This Agreement may be executed in one or more counterparts and, if executed in more than one counterpart, the executed counterparts shall each be deemed to be an original and all such counterparts shall together constitute one and the same instrument.

[Signature Page Follows]

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Please sign and return to the Company the enclosed duplicates of this letter whereupon this letter will become a binding agreement between the Company and the Underwriter in accordance with its terms.

Number of Securities Purchased 770,000

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SCHEDULE I

Issuer General Free Writing Prospectuses

None.

SCHEDULE II

Opinions

SCHEDULE III

NATUS MEDICAL INCORPORATED

List of Subsidiaries

Natus Acquisition Corporation (d/b/a Neometrics, Inc., a Division of Natus) (Delaware)

Natus Neonatal Ltd. (United Kingdom)

Fischer-Zoth Diagnosesysteme GmbH (Germany)

Fischer-Zoth GmbH (Austria)

Fischer-Zoth Modulare Hordiagnostik GmBH & Co KG (German limited partnership)

Deltamed S.A. (France)

Excel Tech Ltd. (Canada)

SCHEDULE IV

On April 4, 2008, the Company priced the transaction that we previously discussed with you. The public offering price was determined to be $18.27 per share or an aggregate $14,067,900 for the 770,000 shares offered. Our underwriting discount is 5%, amounting to a rate of $0.9135 per share (except for the 175,000 shares sold to D³ Family Fund, L.P., D³ Family Canadian Fund, L.P., D³ Family Bulldog Fund, L.P., DIII Offshore Fund, L.P., or affiliated individuals and investment funds, collectively the “D³ Family Funds”) or $543,532.50. The proceeds, before expenses to the Company, are $18.27 on those shares sold to the D³ Family Funds and $17.3565 per share on all other shares sold, or in the aggregate $13,524,368. On April 3, 2008, the last reported sale price of the Company’s common stock on the Nasdaq Global Market was $18.27 per share.

The Company has entered into an underwriting agreement with us with respect to 770,000 shares of common stock which are being offered pursuant to a prospectus supplement. Pursuant to the underwriting agreement the Company has agreed to sell to us, and we have agreed to purchase from the Company, an aggregate of 770,000 shares of common stock.

We propose to offer to the public (including the shares sold to D ³ Family Funds) the shares of common stock purchased pursuant to the underwriting agreement at the public offering price of $18.27 per share. In connection with the sale of the shares of common stock to be purchased by us, we will be deemed to have received compensation in the form of underwriting discounts (except for the shares sold to D³ Family Funds). Our commission and discount (except for the shares sold to D³ Family Funds) will be 5%, amounting to $0.9135 per share of common stock for a total of $543,532.50. The Company will bear the expenses of the offering which are estimated to be $100,000. The net proceeds to the Company, after our commission and discount and the offering expenses, will be $13,424,368.

Pursuant to the underwriting agreement, the Company has agreed to indemnify us, in our role as underwriter, and certain other parties against certain liabilities, including liabilities under the Securities Act, or to contribute to payments which we or such other indemnified parties may be required to make in respect of any such liabilities.

The estimated net proceeds to the Company if it sells the maximum number of shares offered in this offering, including the over-allotment option, will be $15,429,043.25, after deducting our commission and discount and estimated offering expenses of $749,041.75. The Company expects to use the net proceeds to it from this offering for general corporate purposes, which may include the financing of acquisitions of, or investments in, companies and technologies that complement its business, capital expenditures or additions to its working capital.