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Brian O’Neill represents corporations, LLCs, partnerships, directors, officers, and business owners in complex litigation in the Delaware Court of Chancery, Superior Court, U.S. District Court, and Pennsylvania state and federal courts.

Brian serves as counsel to corporations and their directors and officers in litigation arising from deadlocked boards, contested director elections and officer appointments, and breach of fiduciary duty claims. He also represents clients in dissolution proceedings, books and records actions, advancement litigation, and earn-out disputes.

Brian also routinely represents commercial and residential property owners in tax assessment appeal litigation. He has obtained millions of dollars in tax reductions on behalf of his clients collectively over the past twenty years. Brian also defends property owners against tax appeals filed by taxing authorities.

Education

LL.M., Georgetown University Law Center, Washington, DC, 2013, Securities and Financial Regulation
J.D., magna cum laude, Boston University School of Law, Boston, Massachusetts, 1996
B.A., University of Pennsylvania, Philadelphia, Pennsylvania, 1993

State Bar Licenses

Pennsylvania, Delaware, New Jersey

Court Admissions

U.S. Court of Appeals, 3rd Circuit
U.S. District Ct., E.D. of Pennsylvania
U.S. District Ct., District of Delaware
U.S. District Ct., District of New Jersey
  • Lead counsel in the Court of Chancery for a Delaware corporation and its board of directors in a stockholder ownership dispute involving the operations of an Argentine vineyard. Successfully obtained dismissal of the Complaint seeking foreign recognition and enforcement of a judgment from an English Court. D’Aulan v. D’Aulan, 2024 Del. Ch. LEXIS 231 (Del. Ch. June 27, 2024).
  • Lead trial counsel in the Delaware Court of Chancery for a municipality in an action to compel a countywide property tax reassessment based upon non-uniformity under the Delaware State Constitution. Case of first impression under Delaware law whether a municipality has standing to sue for a reassessment. Favorable ruling after the liability phase of trial. Countywide reassessment ordered. In re Delaware Public Schools Litigation, 239 A.3d 451 (Del. Ch. 2020).
  • Lead counsel for a former Mayor of Wilmington in defense of a Section 1983 action involving death and injuries to municipal firefighters. Obtained dismissal of the Complaint in the U.S. District Court of Delaware. Speakman, et al. v. Williams, et al., 2019 WL 4751939 (D. De. Sept. 30, 2019). Dismissal affirmed on appeal to the Third Circuit Court of Appeals. 2021 WL 49947 (3d. Cir. Jan. 6, 2021).
  • Successful defense of a commercial property owner in Montgomery County, Pennsylvania from a challenge by a school district to increase the property tax assessment from $22 million to $38 million.
  • Lead plaintiffs’ counsel in a Section 226 action for five individual directors of a Delaware corporation seeking the appointment of a custodian by the Delaware Court of Chancery to break a deadlock among the ten board members. The action settled favorably after positive pre-trial rulings from the Court.
  • Lead defense counsel in a Section 225 action in the Delaware Court of Chancery defending five managers/directors of a Delaware limited liability company from a challenge to their status as duly elected managers. Action resolved in clients’ favor following positive pre-trial rulings and aggressive discovery strategy.
  • Plaintiff’s counsel to U.S. based investors against a foreign corporation and U.S. based advisors for fraud and breach of contract action in the U.S. District Court for the Eastern District of Pennsylvania. Action settled following favorable rulings on summary judgment motions.