Mark C. O’Connor is a member/shareholder of the firm. Mark is an experienced trial attorney representing clients in a wide range of complex business and commercial matters, providing aggressive and cost-effective representation of clients before federal and state trial courts, government agencies and boards, and arbitration proceedings. He has represented a broad range of clients, from publicly traded corporations to closely-held businesses and entrepreneurial individuals, in many areas of commercial law, including contract disputes, real estate matters, business torts, employment law, intellectual property, telecommunications, environmental, collections, insurance coverage, trusts and estates, and bankruptcy.

Mark also represents employers and employees in all types of litigation involving all aspects of the employment relationship and in a wide variety of employment matters, including, wrongful termination, discrimination, retaliation, breach of employment contract, failure to pay wages, non-compete and non-solicitation agreements, severances, reductions in force, termination and discipline.

He represents and counsels individuals in a wide variety of personal matters and areas including family and domestic matters, partnerships, closely held corporations, limited liability companies, real estate, probate and estate matters, personal injury, and students or minors facing school suspension or school expulsion.

Representative Matters

Representation of Estates and Trusts in litigation with beneficiaries and heirs

Representation of creditors of Chapter 11 and Chapter 7 debtors and defending against claims of preferences

Client counseling and employment litigation involving termination and enforcement of trade secrets and covenants not to compete

Adjudicatory proceedings before the Massachusetts Commission Against Discrimination concerning discrimination in lending practices

Representation of leading mortgage broker in dispute arising out of reverse mortgages

Representation of commercial real estate developers

Successfully represented Boston Latin School student facing expulsion

Successfully represented commercial property owner in construction litigation

Successfully defended a major energy procurement and management firm in a commercial dispute with a customer


Co-Chairperson of the Litigation Practice Group of Ally Law (formerly the International Alliance of Law Firms).

Named a “New England Super Lawyer” by Boston Magazine 2005-2012.

Community Involvement

Trial Court Conferencer for the Boston Municipal Court and active participant of the Massachusetts Boston Municipal Court ADR Program

Judge and former coach of the Massachusetts High School Mock Trials sponsored by the Massachusetts Bar Association

Town of Medfield, Massachusetts, former Housing Authority Trustee

Chairperson of the Noble & Greenough School Parent Fund Raising Committee, 1998

Former member of the President’s Council for the College of the Holy Cross

Coach of the Boston College Mock Trial team in the Regional and National Mock Trial Tournaments

Adjunct Professor of Trial Advocacy at Boston College

Arbitrator for the Massachusetts Executive Office of Consumer Affairs

Professional Affiliations

Massachusetts Defense Lawyers Association

Boston Inn of Court

Churchill Center and Museum

The New England Churchillians

Wisconsin Historical Society

Illinois State Historical Society

Abraham Lincoln Society and Museum

Lincoln Forum, member

Boston Bar Association

Massachusetts Bar Association