(a) Legal Power. Shareholder has the requisite legal power and authority to enterinto this Agreement, to deliver the Shares and to carry out and perform its obligations under theterms of this Agreement, without obtaining the approval or consent of any other party or authority.          (b) Title to Shares. Shareholder owns the Shares free and clear of all liens,charges, claims, encumbrances, security interests, equities, restrictions on transfer or otherdefects in title of any kind or description and, upon delivery of the Shares and receipt of theRepurchase Price therefor, Shareholder will convey to the Company valid and marketable title to theShares, free and clear of all liens, charges, claims, encumbrances, security interests, equities,restrictions on transfer or other defects in title or description.          (c) Investment Representations.               (i) Shareholder is a company in the pharmaceutical industry. Due to Shareholder’spharmaceutical experience, including its experience in maintaining and divesting equity positionsin other pharmaceutical companies, Shareholder possesses the expertise to be able to fend foritself in the transaction contemplated by this Agreement, and is capable of evaluating and bearingthe risks and merits of selling the Shares for the Repurchase Price and pursuant to the terms ofthis Agreement.               (ii) Shareholder has had, during the course of this transaction and prior hereto, theopportunity to ask questions of, and receive answers from, the Company and its managementconcerning the Company, its operations and prospects, and the terms and conditions of thisAgreement.               (iii) Shareholder believes that it has received all such information as it considers necessaryfor evaluating the risks and merits of selling the Shares for the Repurchase Price and pursuant tothe terms of this Agreement and for verifying the accuracy of any information furnished to it or towhich it had access.               (iv) Neither the Company, nor any affiliate of the Company, has made any representations orwarranty, express or implied, regarding any aspect of the transaction except as set forth hereinthis Agreement, and Shareholder is not relying on any such representation or warranty not containedin this Agreement.               (v) Shareholder acknowledges that this Agreement is being entered into during a regularlyscheduled trading black-out under the Company’s Insider Trading Compliance Program and that theCompany may possess or have access to material non-public information which has not beencommunicated to Shareholder.          (d) Acceptance of Risk. Shareholder is entering into this Agreement freely andunderstands and expressly accepts and assumes the economic and market risk associated with sellingthe Shares for the Repurchase Price and agrees that this Agreement shall be in all respectseffective and not subject to termination or rescission under any circumstances.          (e) Tax Consequences. Shareholder acknowledges that the Company is making norepresentation or warranty as to the tax consequences for Shareholder in selling the Shares for theRepurchase Price pursuant to this Agreement. Shareholder further acknowledges that it has had anopportunity to seek independent counsel and advisors with respect to tax and other matters relatingto
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this Agreement, and Shareholder acknowledges and agrees that it shall bear the full taxconsequences, if any, of selling the Shares for the Repurchase Price and pursuant to the terms ofthis Agreement in all circumstances.          (f) US Person. Shareholder is a “United States person” within the meaning of Section7701(a)(30) of the Internal Revenue Code of 1986 as amended.          (g) Indemnification Covenant. Shareholder is aware that the Company is relying uponthe truth of the foregoing representations in this Section 3 in connection with the transaction.Shareholder shall indemnify, protect, defend and hold free and harmless the Company from andagainst all losses resulting from the defense, settlement or compromise of a claim or demand orassessment incurred by the Company as a result of any breach by Shareholder of any of itsrepresentations, warranties or covenants contained in this Agreement.     4. Company Representations. Company represents and warrants to Shareholder that thisAgreement has been duly executed and delivered by the Company and constitutes a legal, valid andbinding obligation of the Company enforceable against the Company in accordance with its terms.     5. Mutual Release.     (a) Except for the duties, obligations and representations set forth in this Agreement, theparties hereto hereby release, discharge and acquit each other, as well as, to the extentapplicable, their respective officers, directors, shareholders, partners, employees, agents,successors and assigns, and any parent, subsidiary or affiliated entity, past, present, or future,from any and all claims, demands, costs, contracts, liabilities, objections, actions and causes ofaction of every nature, whether in law or in equity, known or unknown, suspected or unsuspected,which the parties ever had or now have or may claim to have against each other of any type, natureor description prior to the execution and delivery hereof with respect to or arising from thepurchase or ownership of the Shares by Shareholder. In addition, Shareholder waives any and allclaims it may have or may hereafter acquire against the Company, relating to any failure todisclose non-public information in connection with the transaction.     (b) Waiver of §1542 – Each of the parties acknowledges that each is aware that they mayhereafter discover facts different from or in addition to what such party knows or believes to betrue with respect to the matters released in this Agreement. Each of the parties agrees andacknowledges that the releases granted herein are general releases as to all matters released inthis Agreement. Each of the parties acknowledges that such party has been informed of Section 1542of the Civil Code of the State of California, and does hereby expressly waive and relinquish allrights and benefits which such Party has or may have under that Section, which reads as follows:**“A general release does not extend to claims which thecreditor does not know or suspect to exist in his or her favor at thetime of executing the release, which if known by him or her musthave materially affected his or her settlement with the debtor..”**          6. Miscellaneous.          (a) Entire Agreement. This Agreement represents and contains the full, final andcomplete agreement and understanding between the parties hereto relating to or connected with the
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subject matter hereof. Notwithstanding the foregoing, each party agrees that, at any time and fromtime to time after the date hereof, it will take any and all actions and execute and deliver to anyother party such further instruments or documents as may reasonably be required to give effect tothe intentions of the parties as contemplated under this Agreement. This Agreement shall not beamended except in a writing signed by the parties hereto.          (b) Governing Law and Venue. This Agreement was entered into in the State ofCalifornia, and its validity, construction, interpretation and legal effect shall be governed bythe laws and judicial decisions of the State of California applicable to contracts entered into andperformed entirely within the State of California and by applicable federal law, and thechoice-of-law provisions of California law shall not be applied to substitute the law of any otherState or nation. The parties expressly agree that any action arising out of or relating to thisAgreement shall be filed and maintained only in the courts of the State of California for theCounty of Alameda, or the United States District Court for the Northern District of California.The parties hereby consent and submit to the personal jurisdiction of such courts for the purposesof litigating any such action, and that each such court is a proper venue for litigating any suchaction. Notwithstanding the foregoing, each party agrees that in the event that a party hereto(the “Involved Party”) becomes involved in any legal action with a third party, and either:(i) the other party hereto (the “Non-involved Party”) is a necessary party to theresolution of such legal action, or (ii) the particular legal action gives rise to legal claimsbetween the parties hereto arising out of or relating to this Agreement, then the Non-involvedParty will submit to the personal jurisdiction of the court in which such action is maintained, andaction to resolve such legal claims between the parties may be brought or maintained in the samecourt in which the legal action involving the third party is maintained.          (g) Severability. In the event that any of the provisions of this Agreement shall beheld by a court or other tribunal of competent jurisdiction to be unenforceable, the remainingportions of this Agreement shall remain in full force and effect.          (h) Attorneys’ Fees. In the event that either party to this Agreement shall commenceany action to interpret or enforce this Agreement or any action to enforce or appeal any decisionor judgment rendered in connection therewith, the party in any such action or actions shall recoversuch party’s reasonable costs and expenses incurred in connection therewith, including reasonablyattorneys’ fees.          (i) Specific Performance. Shareholder acknowledges that money damages would not be asufficient remedy for any breach of this Agreement and that irreparable harm would result if thisAgreement were not specifically enforced. Therefore, the rights of the Company and the obligationsof Shareholder under this Agreement shall be enforceable by a decree of specific performance issuedby any court of competent jurisdiction, and appropriate injunctive relief may be applied for andgranted in connection therewith. The Company’s right to specific performance shall be in additionto all other legal or equitable remedies available to the Company.          (j) Headings. The headings of the Sections and subsections contained in thisAgreement are for reference purposes only, and shall not affect the meaning or interpretation ofthis Agreement.          (k) Counterparts. This Agreement may be executed in two or more counterparts, whichshall together constitute one and the same agreement.
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     IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the date first writtenabove.         “COMPANY” “SHAREHOLDER”           QUESTCOR PHARMACEUTICALS, INC.a California corporation SHIRE PHARMACEUTICALS, INC.a Delaware corporation           /s/ George M. Stuart   /s/ Scott Applebaum         George M. Stuart   BY: Scott Applebaum  Senior Vice President, Finance   ITS: Secretary  and Chief Financial Officer        
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EXHIBIT ASTOCK ASSIGNMENT SEPARATE FROM CERTIFICATE     FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers unto QUESTCORPHARMACEUTICALS, INC., a California corporation (the “Company”), 2,155,715 shares of theSeries A Preferred Stock, no par value, of the Company, standing in the undersigned’s name on thebooks of the Company, represented by Certificate No. A-2 herewith, and does hereby irrevocablyconstitute and appoint George M. Stuart, as attorney-in-fact, to transfer said stock on the booksof the Company with full power of substitution in the premises.         Dated: 19 February, 2008   /s/ Scott Applebaum                      SHIRE PHARMACEUTICALS, INC.               BY: Scott Applebaum               ITS: Secretary