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Sean T. Prosser

Class Action, Derivative & Corporate Control Litigation

  • Secured a complete motion to dismiss victory in a securities class action case on behalf of a large multinational operator of membership warehouse clubs, and its former executives. The case, brought in the Southern District of California, centered on allegations that the company misled the public about its performance, among other missteps.
  • Represented a worldwide provider of global IT and enterprise application solutions and its officers and directors in a federal shareholder class action in the Central District of California and in shareholder derivative litigation in California and Nevada state courts. The matters settled on favorable terms.
  • Represented a leading investment company in a pension plan lawsuit filed in the Central District of California. The plaintiff voluntarily dismissed the complaint.
  • Represented investment partnerships in shareholder litigation in the Western District of Washington and District of Idaho arising from EB-5 program and SEC enforcement proceedings.
  • Represented former officers and directors of a restaurant chain operator in connection with breach of fiduciary duty claims by the bankruptcy trustee. The matter was successfully resolved with no payment from the clients.
  • Represented a global specialty pharmaceutical company in a shareholder class action lawsuit arising from its $1.3 billion acquisition of another pharmaceutical company.
  • Represented a manufacturer of specialty chemicals and its directors in shareholder class action lawsuits filed in Nevada State Court and Delaware Chancery Court arising from a $400 million tender offer by investment funds.
  • Represented a multinational holding conglomerate  and its subsidiaries in shareholder class action lawsuits filed in Kansas state and federal courts arising from the company’s $22 billion acquisition of a large US telecommunications company. Successfully won a stay of a parallel federal court proceeding.
  • Represented a multinational holding conglomerate and its subsidiary in a shareholder lawsuit arising from a large US telecommunications company’s $4 billion acquisition of another telecommunications provider.
  • Represented a provider of surgical aesthetics products and its directors in shareholder class actions arising from a $1.1 billion acquisition by a multinational medical devices, pharmaceutical, and consumer packaged goods manufacturing company. Successfully obtained orders denying a motion for preliminary injunction in a California action and staying a parallel Minnesota action. Won summary judgment in the clients’ favor following discovery. Affirmed on appeal.
  • Represented a leading provider of fingerprint identification systems and its directors in shareholder class action lawsuits filed in California state and federal courts and in Delaware Chancery Court arising from the company’s $943 million acquisition by a leading R&D company making a wide range of products. Successfully defeated the plaintiffs’ motion to enjoin the transaction, negotiated voluntary dismissal of the federal lawsuit, and obtained a stay of the parallel California lawsuit. Negotiated a favorable settlement.
  • Represented a company providing fundraising software and its directors and officers in a shareholder derivative lawsuit in San Diego County Superior Court. Following a successful motion to stay discovery and demurrers on behalf of the company and the individuals, the plaintiff dismissed the case.
  • Represented a multinational IT equipment provider and its officers and directors in a federal class action (Central District of California) and state shareholder derivative (Orange County, California) litigation. Favorably settled all litigation following successful federal motions to dismiss.
  • Represented a San Diego–based defense solutions provider and its officers and directors in multiple federal class actions (Southern District of California) and federal and state court shareholder derivative actions (Southern District of California/San Diego Superior Court). Following successful motions, negotiated a favorable global settlement of all matters, including resolution of complex insurance issues.
  • Represented two former officers of a multinational gaming company in connection with a federal class action (District of Nevada) and Nevada state and federal derivative actions. Dismissal of the cases was affirmed on appeal.
  • Represented the former CEO of a diagnostics solutions company in California state court shareholder litigation. Settled with no payment by the client.
  • Represented a company in a control lawsuit involving a closely held company in Delaware Chancery Court before Vice Chancellor Parsons. At trial, the jury decided in the client’s favor.

Internal Investigations

  • Represented a Fortune 100 company in connection with a stockholder books and records inspection demand under Delaware corporate law.
  • Represented the board of a NASDAQ company in connection with stockholder demand under Nevada corporate law.
  • Represented multiple public companies in internal investigations and response to stockholder demands regarding stock option plans.
  • Represented chairman of the board of a multibillion-dollar medical diagnostic company in connection with an internal audit committee investigation and a NASDAQ investigation regarding disclosure issues.
  • Represented a special committee of a public biotechnology company regarding an internal investigation in response to a shareholder demand letter regarding a stock option plan.
  • Represented the chief executive officer of a public technology company in connection with an internal audit committee investigation.
  • Represented the audit committee of a $1 billion public communications company in connection with an internal investigation and an SEC inquiry arising from an accounting restatement.
  • Represented the special committee of a public technology company in connection with an internal investigation and an SEC inquiry regarding stock option backdating issues.
  • Represented multiple public companies in connection with internal investigations stemming from purported whistleblower complaints.
  • Represented multiple individual officers, directors, and employees of public companies in connection with internal investigations.

White Collar & Regulator Enforcement Investigations and Proceedings

  • Represented a US-based trader in an SEC lawsuit and a DOJ investigation arising from the Ukrainian hack of the SEC’s EDGAR database (District of New Jersey).
  • Represented foreign defendants in an SEC insider-trading action arising from alleged misappropriation of an investment bank’s information (Southern District of New York).
  • Represented multiple companies and executives in US Attorney investigations and Grand Jury proceedings.
  • Represented the Corporate Monitor of a large multinational medical device company arising from joint SEC and DOJ actions under the US Foreign Corrupt Practices Act (FCPA).
  • Represented the appointed Independent Manager of EB-5 Funds and related companies arising from SEC enforcement action.
  • Represented multiple securities traders in SEC insider-trading investigations.
  • Represented an individual regarding an investigation by the SEC’s Los Angeles office into capital raising by an electronics company.
  • Represented securities traders in an investigation by the SEC’s Chicago office related to alleged market manipulation activities.
  • Represented an NYSE-listed company in an investigation by the Financial Industry Regulatory Authority (FINRA) regarding disclosure and securities trading activities.
  • Represented investment advisors and brokers in multiple FINRA investigations.
  • Represented a major apparel company in an investigation by the SEC’s Los Angeles office related to securities disclosure issues.
  • Represented the CFO of a technology company in an investigation by the SEC’s Home Office regarding selective disclosure issues.
  • Represented a medical device company in a med corporation in a public SEC investigation related to matters concerning a then-pending FDA application for approval of silicone breast implant devices. The investigation closed with no enforcement recommendation.
  • Represented a $1+ billion foreign company and a principal shareholder in a DOJ investigation, grand jury, and asset-blocking action by the Office of Foreign Assets Control (OFAC).
  • Represented a former general counsel of a public biotechnology company in connection with a joint SEC and DOJ investigation into Foreign Corrupt Practices Act (FCPA) issues involving China.
  • Represented a former general manager of a Chinese company in connection with an SEC investigation into FCPA issues involving a US public company.
  • Represented the chief scientist of a public life sciences company in connection with SEC and DOJ investigations regarding test data. The investigations closed with no enforcement recommendations as to the client.
  • Represented an entertainment company in an SEC investigation regarding film financing.
  • Represented a public accounting firm and CPAs in multiple SEC investigations conducted by Denver, New York, Washington, DC, Chicago, and Miami offices.
  • Represented a securities trading software and education company in an SEC investigation.
  • Represented a broker-dealer in an SEC investigation regarding cherry-picking activities by hedge fund customers. No enforcement action was taken against the broker-dealer client.
  • Represented a broker-dealer and an investment advisor in connection with federal grand jury and other government proceedings relating to potential money laundering issues.
  • Represented a broker-dealer in a FINRA investigation regarding registered foreign agents and anti-money laundering issues.
  • Represented a secretary of a former senior US House of Representatives member in connection with grand jury proceedings.
  • Represented a former officer of a public gaming company in an SEC enforcement action and litigation alleging insider trading based on non-public material information concerning the company’s financial performance.
  • Represented a publishing company in connection with an investigation by the SEC’s Pacific Regional Office arising from a $250 million accounting restatement.
  • Represented a San Diego City Council member and former acting mayor in an SEC investigation related to municipal bond offering disclosures.
Case Study
Mintz’s Securities Litigation team achieved a full dismissal at the pleading stage of a putative securities class action case filed against client PriceSmart, Inc. and its former executives.