Mark Rosen represents clients in high-stakes business litigation and provides counseling on complex legal challenges. Mark focuses on commercial and class action litigation as well as matters of corporate governance. He represents companies and financial services firms in class action litigation, securities litigation, and complex business litigation including breach of contract actions arising out of commercial transactions, business combinations, privatizations and financings. Mark also represents owners and contractors in construction disputes and litigation concerning complex commercial projects and the award of government contracts.

In his commercial litigation and government investigation practice, Mark routinely navigates complex electronic discovery issues, with a focus on the efficient execution of large-scale productions of electronically stored information while protecting client trade secrets and confidential material.

In addition to his litigation practice, Mark provides counseling on corporate governance matters, including the fiduciary duties of corporate directors and officers, regulatory compliance and insider trading issues. He has conducted internal investigations on behalf of boards of directors, audit committees and companies. Mark has also represented companies and individuals in SEC investigations. Before joining Pierce Atwood in 2010, Mark practiced in the Securities Litigation and Corporate Governance Group at Weil, Gotshal & Manges LLP in New York.

Professional Activities

Member, New Hampshire Bar Association

Civic Activities

  • Treasurer, Board of Directors, Tenants Association at Pease, Inc.
  • Secretary, Board of Directors, Brixham Montessori Friends School
  • Pro bono counsel for underserved clients referred by the New Hampshire Legal Advice and Referral Center

Practice Areas

Representative Experience

  • M&A and shareholder litigation: Represents the directors of a public company in the high tech and energy sectors in a shareholder class action alleging breach of fiduciary duties in the approval of a merger transaction. Also represents a minority shareholder of an automotive company in a dispute over the fairness and propriety of a recent management buyout. Successfully represented a medical devices company and its board of directors in a shareholder challenge to the company’s preferred stock financing. Routinely represents purchasers and target companies in disputes over corporate M&A transactions.
  • Government investigations:  Represents the former controller of a large New England ski resort in an SEC investigation into the resort’s use and accounting of capital funds obtained through two private offerings.   
  • Shareholder securities fraud class actions: In 2012-13, successfully defended a New Hampshire public company in a Rule 10b-5 class action alleging misrepresentations and omissions in the company’s SEC filings. In 2010, represented private real estate partnerships and their principals in a securities fraud suit brought by limited partner investors. In a complete victory, won dismissal, with prejudice, of the complaint's federal securities and state-law breach of fiduciary duty claims.
  • Construction litigation: Recently represented the local subsidiary of an international energy company in a dispute with a contractor over change order requests in a complex project involving improvements to a regional power grid. Representing the owner of a large biotech facility and its prime contractor in a breach of contract action brought by a subcontractor over denied change order requests, successfully appealed a judgment against the owner and prime contractor, with the judgment vacated by the New Hampshire Supreme Court. Recently represented an environmental company in a dispute with a general contractor over the award of a government contract. Currently represents a utility company in a dispute with a contractor over a denied change order request that sought to dramatically increase the contract price for the construction of electrical power transmission lines.
  • Consumer class actions: Recently defended an internet marketing company in a consumer fraud class action and obtained summary judgment in favor of the defendants.
  • Employment litigation: On behalf of an Arizona-based high-tech company, obtained dismissal of a former employee’s discrimination and retaliation claims. Also represented the former executive of a public company in a dispute over the executive's separation from the company and his entitlement to stock options, and successfully obtained dismissal of the company’s misappropriation of trade secrets, nondisclosure, and unfair trade practices claims.