J.P. MORGAN SECURITIES INC.

Exhibit 1.1

J.P. MORGAN SECURITIES INC.

SONIC SOLUTIONS

1,300,000 Shares of Common Stock

Underwriting Agreement

June 23, 2004                

J.P. Morgan Securities Inc.

277 Park Avenue

New York, New York 10172

Ladies and Gentlemen:

Sonic Solutions, a California corporation (the “Company”), proposes to issue and sell to J.P. Morgan Securities Inc., as underwriter (the “Underwriter”), an aggregate of 1,300,000 shares of common stock, no par value (the “Common Stock”), of the Company (the “Underwritten Shares”).

The Company hereby confirms its agreement with the Underwriter concerning the purchase and sale of the Underwritten Shares, as follows:

1. Registration Statement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement (File No. 333-112523), including a prospectus relating to certain securities of the Company, including the Common Stock (the “Basic Prospectus”). Such registration statement, as amended as of the date of this Agreement and, in the event any post-effective amendment thereto becomes effective prior to the Closing Date (as defined in Section 2(c) hereof) is referred to herein as the “Registration Statement.” As used herein, the term “Preliminary Prospectus” means any preliminary prospectus supplement to the Basic Prospectus relating to the Underwritten Shares, together with the Basic Prospectus, and the term “Final Prospectus” means the final prospectus supplement to the Basic Prospectus relating to the Underwritten Shares in the form first used to confirm sales of the Underwritten Shares, together with the Basic Prospectus. If the Company has filed a registration statement pursuant to Rule 462(b) under the Securities Act (the “Rule 462 Registration Statement”), then any reference herein to the term “Registration Statement” shall be deemed to include such Rule 462 Registration Statement. Any reference in this Agreement to the Registration Statement, any

Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of such Preliminary Prospectus or the Final Prospectus, as the case may be, and any reference to “amend,” “amendment” or “supplement” with respect to the Registration Statement, any Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”) that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Final Prospectus.

2. Purchase of the Underwritten Shares by the Underwriter. (a) The Company agrees to issue and sell the Underwritten Shares to the Underwriter as provided in this Agreement, and the Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees to purchase from the Company the Underwritten Shares at a purchase price per share of $18.45 (the “Purchase Price”).

(b) The Company understands that the Underwriter intends to make a public offering of the Underwritten Shares as soon after the effectiveness of this Agreement as in the judgment of the Underwriter is advisable, and initially to offer the Underwritten Shares on the terms set forth in the Final Prospectus. The Company acknowledges and agrees that the Underwriter may offer and sell Underwritten Shares to or through any affiliate of the Underwriter and that any such affiliate may offer and sell Underwritten Shares purchased by it to or through the Underwriter.

(c) Payment for the Underwritten Shares shall be made by wire transfer in immediately available funds to the account specified by the Company to the Underwriter, at the offices of Davis Polk & Wardwell at 7:00 A.M. San Francisco time on June 28, 2004, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Underwriter and the Company may agree upon in writing. The time and date of such payment for the Underwritten Shares is referred to herein as the “Closing Date.”

Payment for the Underwritten Shares to be purchased on the Closing Date shall be made against delivery to the Underwriter for the account of the Underwriter of the Underwritten Shares to be purchased on such date through the facilities of The Depository Trust Company for the respective accounts and in such denominations as the Underwriter shall request in writing not later than two full business days prior to the Closing Date, with any transfer taxes payable in connection with the sale of the Underwritten Shares duly paid by the Company.

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

(a) Registration Statement and Final Prospectus. No order suspending the effectiveness of the Registration Statement has been issued by the Commission and no proceeding for that purpose has been initiated or, to the Company’s knowledge, threatened by the Commission; as of the applicable effective date of the Registration Statement and any amendment thereto, the Registration Statement complied and will comply in all material respects with the Securities 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 in order to make the statements therein not misleading; and as of the applicable filing date of the Final Prospectus and any amendment or supplement thereto and as of the Closing Date, the Final Prospectus will 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 the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to the Underwriter furnished to the Company in writing by the Underwriter expressly for use in the Registration Statement and the Final Prospectus and any amendment or supplement thereto.

(b) Incorporated Documents. The documents incorporated by reference in the Final 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, when read together with the other information in the Prospectus, do 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.

(c) Financial Statements. The Company’s financial statements and the related notes thereto included or incorporated by reference in the Registration Statement and the Final Prospectus comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and present fairly, in all material respects, the financial position of the Company and its subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified, subject to normal year-end adjustments; such financial statements have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods covered thereby, and the supporting schedules included or incorporated by reference in the Registration Statement present fairly, in all material respects, the information required to be stated therein; and the other financial information included or incorporated by reference in the Registration Statement and the Final Prospectus has been derived from the accounting records of the Company and its subsidiaries and presents fairly, in all material respects, the information of the Company shown thereby.

(d) No Material Adverse Change. Since the date of the most recent financial statements of the Company included or incorporated by reference in the Registration Statement

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and the Final Prospectus, (i) there has not been any change in the capital stock (other than pursuant to the exercise of stock options or warrants to purchase Common Stock and purchases of Common Stock pursuant to the Company’s employee stock purchase plan as disclosed in the Registration Statement and the Final Prospectus) or long-term debt of the Company or any 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 which could reasonably be expected to have a material adverse change, in or affecting the business, properties, management, financial position, stockholders’ equity or results of operations of the Company and its subsidiaries, taken as a whole; (ii) neither the Company nor any of its subsidiaries has entered into any transaction or agreement that is material to the Company and its subsidiaries taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiaries taken as a whole which is not disclosed in the Registration Statement and the Final Prospectus; and (iii) neither the Company nor any of its subsidiaries has 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, except in each case as otherwise disclosed in the Registration Statement and the Final Prospectus.

(e) Organization and Good Standing. The Company and each of its subsidiaries have been duly organized and are validly existing and in good standing under the laws of their respective jurisdictions of organization, are duly qualified to do business and are in good standing in each jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such qualification, and have all corporate power and authority necessary to own or hold their respective properties and to conduct the businesses in which they are engaged, except where the failure to be so qualified or have such power or authority would not, individually or in the aggregate, have a material adverse effect on the business, properties, management, financial position, stockholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole (a “Material Adverse Effect”).

(f) Capitalization. The Company has an authorized capitalization as set forth in the Final Prospectus under the heading “Capitalization” (other than for subsequent issuances, if any, pursuant to employee benefit plans described in the Final Prospectus or upon the exercise of outstanding options or warrants described in the Final Prospectus); all the outstanding shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable and are not subject to any pre-emptive or similar rights; except as described in or expressly contemplated by the Final Prospectus, there are no outstanding rights (including, without limitation, pre-emptive rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other equity interest in the Company or any of its subsidiaries, or any contract, commitment, agreement, understanding or arrangement of any kind relating to the issuance of any capital stock of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock of the Company conforms in all material respects to the description thereof contained in the Registration Statement and the Final Prospectus; and all the outstanding shares of capital stock or other equity interests of each subsidiary of the Company have been duly and validly authorized and

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issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party.

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

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

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

(j) No Violation or Default. Neither the Company nor any of its subsidiaries is (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 any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject; 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 clauses (ii) and (iii) above, for any such default or violation 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 this Agreement, the issuance and sale of the Underwritten Shares to be sold by the Company hereunder and the consummation by the Company of the transactions contemplated by this Agreement 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 any of its subsidiaries pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, (ii) result in any violation of the provisions of the charter or by-laws or similar organizational documents of the Company or any of its subsidiaries or (iii) except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect, 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.

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(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 this Agreement, the issuance and sale of the Underwritten Shares to be sold by the Company hereunder and the consummation by the Company of the transactions contemplated hereby, except for the registration of the Underwritten Shares under the Securities Act and such consents, approvals, authorizations, orders and registrations or qualifications as may be required under applicable state securities laws in connection with the purchase and distribution of the Underwritten Shares by the Underwriter or the failure to obtain which would not reasonably be expected to have a Material Adverse Effect or materially adversely affect the transactions contemplated hereby.

(m) Legal Proceedings. Except as described in the Final Prospectus or Registration Statement, there are no legal, governmental or regulatory investigations, actions, suits or proceedings pending to which the Company or any of its subsidiaries is or may be a party or to which any property of the Company or any of its subsidiaries is or may be the subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, could reasonably be expected to have a Material Adverse Effect or materially and adversely affect the ability of the Company to perform its obligations hereunder; to the Company’s knowledge, no such investigations, actions, suits or proceedings have been threatened or, to the knowledge of the Company, contemplated by any governmental or regulatory authority or threatened by others and (x) there are no current or pending legal, governmental or regulatory actions, suits or proceedings that are required under the Securities Act to be described in the Final Prospectus or Registration Statement that are not so described and (y) there are no statutes, regulations or contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement or described in the Registration Statement or the Final Prospectus that are not so filed or described.

(n) Independent Accountants. KPMG LLP, who have certified certain financial statements (including the related notes) of the Company and its subsidiaries, are independent public accountants with respect to the Company and its subsidiaries as required by the Securities Act.

(o) Title to Real and Personal Property. The Company and its subsidiaries have good title in fee simple to, or have valid rights to lease or otherwise use, all items of real and personal property that are material to the respective businesses of the Company and its subsidiaries, in each case free and clear of all liens, encumbrances, claims and defects and imperfections of title 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) could not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(p) Rights to Intellectual Property. Except as described in the Final Prospectus, the Company and its subsidiaries own or possess the right to use all patents, trademarks, trademark registrations, service marks, service mark registrations, trade names,

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copyrights, licenses, inventions, trade secrets, know-how and other intellectual property rights which are necessary for their respective businesses as described in the Final Prospectus, including, without limitation, those intellectual property rights described in the Final Prospectus as being owned by them for the conduct of their respective businesses, except where the failure to own or possess such intellectual property rights would not reasonably be expected to, individually or in the aggregate, have a Material Adverse Effect. Except as described in the Final Prospectus, the Company is not aware of any claim filed against the Company to the contrary or any written challenge by any other person to the rights of the Company or its subsidiaries, with respect to the foregoing, other than any such claim or challenge that would not reasonably be expected to, individually or in the aggregate, have a Material Adverse Effect. To the knowledge of the Company, neither the Company nor any of its subsidiaries infringes any trademarks, service marks, trade names, copyrights, trade secrets, licenses, know-how or patents or other intellectual property or franchise right of any person, other than any infringement or conflict that would not reasonably be expected to, individually or in the aggregate, have a Material Adverse Effect.

(q) No Undisclosed Relationships. No relationship, direct or indirect, exists between or among the Company or any of its subsidiaries, on the one hand, and the directors, officers, stockholders, customers or suppliers of the Company or any of its subsidiaries, on the other, that is required by the Securities Act to be described in the Registration Statement and the Final Prospectus and that is not so described.

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

(s) Taxes. The Company and its subsidiaries have paid all federal, state, local and foreign taxes and filed all tax returns required to be paid or filed through the date hereof, and except where the failure to file such returns and make such payments would not, individually or in the aggregate reasonably be expected to have a Material Adverse Effect. Except as otherwise disclosed in the Final Prospectus, there is no tax deficiency that has been, or could reasonably be expected to be, asserted against the Company or any of its subsidiaries or any of their respective properties or assets.

(t) Licenses and Permits. The Company and its subsidiaries possess 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 Final Prospectus, except where the failure to possess or make the same would not, individually or in the aggregate, have a Material Adverse Effect; and except as described in the Final Prospectus, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such license,

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certificate, permit or authorization or has any reason to believe that any such license, certificate, permit or authorization will not be renewed in the ordinary course, subject in each case to such qualification as may be set forth in the Registration Statement or the Final Prospectus and except to the extent that any such revocation, individually or in the aggregate, could not reasonably be expected to have a Material Adverse Effect.

(u) No Labor Disputes. No material labor disturbance by or dispute with employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is contemplated or threatened.

(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; 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 any such case for any such failure to comply, or failure to receive required permits, licenses or approvals, or liability as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

(w) Compliance with ERISA. Except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect, each 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 affiliates has been maintained in compliance in all material respects 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 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) Accounting 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 appropriate action is taken with respect to any differences.

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(y) Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, which insurance is in amounts and insures against such losses and risks as the Company reasonably considers are adequate, and are reasonably consistent with industry standards, to protect the Company and its subsidiaries and their respective businesses; and neither the Company nor any of its subsidiaries has (i) received notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in order to continue such insurance or (ii) any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage at reasonable cost from similar insurers as may be necessary to continue its business.

(z) No Restrictions on Subsidiaries. No subsidiary of the Company is currently prohibited, directly or indirectly, under any agreement or other instrument to which it is a party or is subject, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s properties or assets to the Company or any other subsidiary of the Company.

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

(bb) No Registration Rights. No person has the right to require the Company or any of its subsidiaries to register any securities for sale under the Securities Act by reason of the filing of any Preliminary Prospectus or the Final Prospectus with the Commission or the issuance and sale of the Underwritten Shares to be sold by the Company hereunder.

(cc) 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 Underwritten Shares.

(dd) Margin Rules. Neither the issuance, sale and delivery of the Underwritten Shares nor the application of the proceeds thereof by the Company as described in the Registration Statement and the Final Prospectus will violate Regulation T, U or X of the Board of Governors of the Federal Reserve System or any other regulation of such Board of Governors.

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

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(ff) Statistical and Market Data. Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included in the Registration Statement and the Final Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

(gg) Sarbanes-Oxley. There is and has been no failure on the part of the Company or any of the Company’s directors or officers, in their capacities as such, to comply with any provision of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith (the “Sarbanes-Oxley Act”), that are effective as of the date hereof, including Section 402 related to loans and Sections 302 and 906 related to certifications.

(hh) Nasdaq. The Underwritten Shares have been approved for listing on the Nasdaq National Market (the “Nasdaq”), subject to notice of issuance. There is and has been no failure on the part of the Company to comply with the applicable rules and regulations relating to independence and corporate governance of Nasdaq.

(ii) No Rated Securities. There are no securities or preferred stock of or guaranteed by the Company or any of its subsidiaries accorded a rating by a “nationally recognized statistical rating organization,” as such term is defined by the Commission for purposes of Rule 436(g)(2) under the Securities Act.

(jj) No Significant Subsidiaries. There is no subsidiary of the Company that would constitute a “significant subsidiary” as such term is defined under Rule 1-02(w) of Regulation S-X of the Commission as in effect on the date of the Registration Statement and Final Prospectus.

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

(a) Effectiveness of the Registration Statement. The Company will file the Final Prospectus with the Commission within the time periods specified by Rule 424(b) and will file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Final Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Underwritten Shares; and the Company will furnish copies of the Final Prospectus to the Underwriter in New York City prior to 10:00 A.M., New York City time, on the business day next succeeding the date of this Agreement in such quantities as the Underwriter may reasonably request.

(b) Delivery of Copies. The Company will deliver, without charge, (i) to the Underwriter, a signed copy of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith and documents incorporated by reference therein, and (ii) to the Underwriter (A) a conformed copy of the Registration Statement as originally filed and each amendment thereto (without exhibits) and (B)

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during the Prospectus Delivery Period, as many copies of the Final Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein) as the Underwriter may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Underwritten Shares as in the opinion of counsel for the Underwriter a prospectus relating to the Underwritten Shares is required by law to be delivered in connection with sales of the Underwritten Shares by the Underwriter or any dealer.

(c) Amendments or Supplements. Before filing any amendment or supplement to the Registration Statement or the Final Prospectus, the Company will furnish to the Underwriter and counsel for the Underwriter a copy of the proposed amendment or supplement for review and will not file any such proposed amendment or supplement to which the Underwriter reasonably objects.

(d) Notice to the Underwriter. The Company will advise the Underwriter promptly, and confirm such advice in writing, (i) when any amendment to the Registration Statement has been filed or becomes effective; (ii) when any amendment or supplement to the Final Prospectus has been filed; (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Final Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (iv) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus or the Final Prospectus or the initiation or threatening of any proceeding for that purpose; (v) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Final Prospectus as then amended or supplemented would 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 existing when the Final Prospectus is delivered to a purchaser, not misleading; and (vi) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Underwritten Shares for offer and sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and the Company will use its best efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus or the Final Prospectus or suspending any such qualification of the Underwritten Shares and, if any such order is issued, will obtain as soon as possible the withdrawal thereof.

(e) Ongoing Compliance. If during the Prospectus Delivery Period (i) any event shall occur or condition shall exist as a result of which the Final Prospectus as then amended or supplemented would include an 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 the light of the circumstances existing when the Final Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Final Prospectus to comply with law, the Company will immediately notify the Underwriter thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission and furnish to the Underwriter and to such dealers as the Underwriter may designate, such amendments or supplements to the Final Prospectus as may be necessary so that the statements in the Final Prospectus as so amended or supplemented will not, in the light of the circumstances existing when the Final Prospectus is delivered to a purchaser, be misleading or so that the Final Prospectus will comply with law.

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(f) Further Filings with the Commission. Any further documents filed with the Commission and incorporated by reference in the Final Prospectus, when such documents become effective or are filed with the Commission, as the case may be, will conform in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, 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, in the light of the circumstances under which they were made, not misleading.

(g) Blue Sky Compliance. The Company will qualify the Underwritten Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Underwriter shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Underwritten Shares; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(h) Earning Statement. The Company will make generally available to its security holders and the Underwriter as soon as practicable an earning statement that satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 of the Commission promulgated thereunder covering a period of at least twelve months beginning on the first day of the first full fiscal quarter after the date of this Agreement.

(i) Use of Proceeds. The Company will apply the net proceeds from the sale of the Underwritten Shares as described in the Final Prospectus under the heading “Use of Proceeds.”

(j) No Stabilization. The Company will not take, 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 Underwritten Shares.

(k) Listing of Underwritten Shares. The Company will use its best efforts to list, subject to notice of issuance, the Underwritten Shares on the Nasdaq.

5. Conditions of Underwriter’s Obligations. The obligation of the Underwriter to purchase the Underwritten Shares on the Closing Date, as provided herein, is subject to the performance by the Company of its covenants and other obligations hereunder and to the following additional conditions:

(a) Registration Compliance; No Stop Order. No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose shall be pending before or threatened by the Commission; the Final Prospectus shall have been

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timely filed with the Commission under the Securities Act and in accordance with Section 4(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Underwriter.

(b) Representations and Warranties. The representations and warranties of the Company contained herein shall be true and correct on the date hereof and on and as of the Closing Date; and the statements of the Company and its officers made in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date.

(c) No Material Adverse Change. Subsequent to the execution and delivery of this Agreement, no event or condition of a type described in Section 3(e) hereof shall have occurred or shall exist, which event or condition is not described in the Final Prospectus (excluding any amendment or supplement thereto) and the effect of which in the judgment of the Underwriter makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Underwritten Shares on the Closing Date, on the terms and in the manner contemplated by this Agreement and the Final Prospectus.

(d) Officer’s Certificate. The Underwriter shall have received on and as of the Closing Date a certificate of the chief executive officer and the chief financial officer of the Company (i) confirming that such officers have carefully reviewed the Registration Statement and the Final Prospectus and, to the best knowledge of such officers, the representation of the Company set forth in Section 3(b) hereof is true and correct, (ii) confirming that the other representations and warranties of the Company in this Agreement are true and correct and that the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to such Closing Date and (iii) to the effect set forth in paragraphs (a), (b), (c) and (d) above.

(e) Comfort Letters. On the date of this Agreement and on the Closing Date, KPMG LLP shall have furnished to the Underwriter, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriter, in form and substance reasonably satisfactory to the Underwriter, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Registration Statement and the Final Prospectus; provided that the letter delivered on the Closing shall use a “cut-off” date no more than three business days prior to such Closing Date.

(f) Opinion of Counsel for the Company. Morrison & Foerster LLP, counsel for the Company, shall have furnished to the Underwriter, at the request of the Company, their written opinion, dated the Closing Date, and addressed to the Underwriter, in form and substance reasonably satisfactory to the Underwriter, to the effect set forth in Exhibit A hereto.

(g) Opinion of Counsel for the Underwriter. The Underwriter shall have received on and as of the Closing an opinion of Davis Polk & Wardwell, counsel for the Underwriter, with respect to such matters as the Underwriter may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

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(h) No Legal Impediment to Issuance. No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would, as of the Closing Date, prevent the issuance or sale of the Underwritten Shares; and no injunction or order of any federal, state or foreign court shall have been issued that would, as of the Closing Date.

(i) Additional Documents. On or prior to the Closing Date, the Company shall have furnished to the Underwriter such further certificates and documents as the Underwriter may reasonably request.

All opinions, letters, certificates and evidence mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriter.

6. Indemnification and Contribution.

(a) Indemnification of the Underwriter. The Company agrees to indemnify and hold harmless the Underwriter, its affiliates, directors and officers and each person, if any, who controls the Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement, any Preliminary Prospectus or the Final Prospectus (or any amendment or supplement thereto), 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 relating to the Underwriter furnished to the Company in writing by the Underwriter expressly for use therein, it being understood and agreed that the only such information furnished by the Underwriter consists of the information described as such in subsection (b) below; provided that with respect to any such untrue statement in or omission from any Preliminary Prospectus, the indemnity agreement contained in this paragraph (a) shall not inure to the benefit of the Underwriter from whom the person asserting any such losses, claims, damages or liabilities purchased Underwritten Shares, or any person controlling the Underwriter, if a copy of the Prospectus (as then amended or supplemented if the Company shall have furnished any amendments or supplements thereto) was not sent or given by or on behalf of the Underwriter to such person, if required by law so to have been delivered, at or prior to the written confirmation of the sale of the Underwritten Shares to such person, and if the Final Prospectus (as so amended or supplemented) would have cured the defect giving rise to such losses, claims, damages or liabilities, unless such failure is the result of noncompliance by the Company with the provisions of Section 4 hereof.

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(b) Indemnification of the Company. The Underwriter agrees to indemnify and hold harmless the Company, its directors, its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Securities 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 relating to the Underwriter furnished to the Company in writing by the Underwriter expressly for use in the Registration Statement, any Preliminary Prospectus and the Final Prospectus (or any amendment or supplement thereto), it being understood and agreed upon that the only such information furnished by the Underwriter consists of the following information in the Final Prospectus furnished on behalf of the Underwriter: paragraph 7 under the caption “Underwriting.”

(c) Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought 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 6 except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; 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 6. If any such proceeding shall be brought 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 6 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 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 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 Underwriter, its affiliates,

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directors and officers and any control persons of the Underwriter shall be designated in writing by J.P. Morgan Securities Inc. 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 effected without its written consent, but if settled with such consent or if there be a final judgment 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 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 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. 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 hand and the Underwriter on the other from the offering of the Underwritten 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 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 respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Underwritten Shares and the total underwriting discounts and commissions received by the Underwriter in connection therewith, in each case as set forth in the table on the cover of the Final Prospectus, bear to the aggregate offering price of the Underwritten Shares. The relative fault of the Company on the one hand and the Underwriter 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 Underwriter and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

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(e) Limitation on Liability. The Company and the Underwriter agree that it would not be just and equitable if contribution pursuant to this Section 6 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 6, in no event shall the Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by the Underwriter with respect to the offering of the Underwritten Shares 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.

(f) Non-Exclusive Remedies. The remedies provided for in this Section 6 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.

7. Termination. This Agreement may be terminated in the absolute discretion of the Underwriter, by notice to the Company, if after the execution and delivery of this Agreement and prior to the Closing Date, (i) trading generally shall have been suspended or materially limited on or by any of the New York Stock Exchange, the American Stock Exchange, the National Association of Securities Dealers, Inc., the Chicago Board Options Exchange, the Chicago Mercantile Exchange or the Chicago Board of Trade; (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 shall have occurred any outbreak or escalation of hostilities or any change in financial markets or any calamity or crisis, either within or outside the United States, that, in the judgment of the Underwriter, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Underwritten Shares on the Closing Date, on the terms and in the manner contemplated by this Agreement and the Final Prospectus.

8. Payment of Expenses. (a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay or cause to be paid all costs and expenses incident to the performance of its obligations hereunder, including without limitation, (i) the costs incident to the authorization, issuance, sale, preparation and delivery of the Underwritten Shares and any taxes payable in that connection; (ii) the costs incident to the preparation, printing and filing under the Securities Act of the Registration Statement and the Final Prospectus (including all exhibits, amendments and supplements thereto) and the

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distribution thereof; (iii) the fees and expenses of the Company’s counsel and independent accountants; (iv) the fees and expenses incurred in connection with the registration or qualification and determination of eligibility for investment of the Underwritten Shares under the laws of such jurisdictions as the Underwriter may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related fees and expenses of counsel for the Underwriter); (v) the cost of preparing stock certificates; (vi) the costs and charges of any transfer agent and any registrar; (vii) all expenses and application fees incurred in connection with any filing with, and clearance of the offering by, the National Association of Securities Dealers, Inc.; and (viii) all expenses and application fees related to the listing of the Underwritten Shares on the Nasdaq.

(b) If (i) this Agreement is terminated pursuant to Section 7, (ii) the Company for any reason fails to tender the Underwritten Shares for delivery to the Underwriter or (iii) the Underwriter declines to purchase the Underwritten Shares for any reason permitted under this Agreement, the Company agrees to reimburse the Underwriter for all out-of-pocket costs and expenses (including the fees and expenses of their counsel) reasonably incurred by the Underwriter in connection with this Agreement and the offering contemplated hereby.

9. 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 the officers and directors and any controlling persons referred to in Section 6 hereof. Nothing 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 provision contained herein. No purchaser of Underwritten Shares from the Underwriter shall be deemed to be a successor merely by reason of such purchase.

10. Survival. The respective indemnities, rights of contribution, representations, warranties and agreements of the Company and the Underwriter contained in this Agreement or made by or on behalf of the Company or the Underwriter pursuant to this Agreement or any certificate delivered pursuant hereto shall survive the delivery of and payment for the Underwritten Shares and shall remain in full force and effect, regardless of any termination of this Agreement or any investigation made by or on behalf of the Company or the Underwriter.

11. Certain Defined Terms. For purposes of this Agreement, (a) except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under the Securities Act; (b) the term “business day” means any day other than a day on which banks are permitted or required to be closed in New York City.

12. Miscellaneous.

(a) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriter shall be given to it at J.P. Morgan Securities Inc., 277 Park Avenue, New York, New York 10172 (fax: (212) 622-2071), Attention: Equity Capital Markets; with a copy to Davis Polk & Wardwell, 1600 El Camino

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Real, Menlo Park, California 94025 (fax: (650) 752-2111), Attention: Francis S. Currie. Notices to the Company shall be given to it at Sonic Solutions, 101 Rowland Way, Suite 110, Novato, California 94945 (fax: (415) 893-3008), Attention: Robert J. Doris; with a copy to Morrison & Foerster LLP, 1290 Avenue of the Americas, New York, New York 10104 (fax: (212) 468-7900), Attention: James R. Tanenbaum.

(b) Governing Law. This Agreement shall be governed by and construed in accordance with the laws of the State of New York.

(c) Counterparts. This Agreement may be signed in counterparts (which may include counterparts delivered by any standard form of telecommunication), each of which shall be an original and all of which together shall constitute one and the same instrument.

(d) Amendments or Waivers. No amendment or waiver of any provision of this Agreement, nor any consent or approval to any departure therefrom, shall in any event be effective unless the same shall be in writing and signed by the parties hereto.

(f) Headings. The headings herein are included for convenience of reference only and are not intended to be part of, or to affect the meaning or interpretation of, this Agreement.

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If the foregoing is in accordance with your understanding, please indicate your acceptance of this Agreement by signing in the space provided below.

Accepted: June 23, 2004