David B. Mack

Partner with OCM since 2005
781.359.9005 | 781.359.9001 | dmack@ocmlaw.net
david mack

David has been a commercial litigator since 1995, and has extensive trial and appellate experience in both the state and federal courts. Mr. Mack advises individuals, public and private companies on a wide range of matters, with a particular emphasis on landlord-tenant, real estate and insurance coverage disputes. Mr. Mack provides practical, efficient advice to clients suitable to the particular circumstances at hand.

In 2009, a Massachusetts court, in awarding attorneys fees to OCM’s client in an insurance coverage dispute, enhanced the fee award by 50% on account of the effectiveness and efficiency of the services provided. Mr. Mack joined the Firm in 2005 after spending ten years in the litigation departments of the Boston firms Hutchins, Wheeler & Dittmar, P.C. and Nixon Peabody LLP.

Some of Mr. Mack’s recent accomplishments include:

  • Jury verdict in a commercial lease dispute on behalf of a shopping mall owner.
  • $4.5 million judgment against a prominent life insurance company for unfair claims settlement practices.
  • Jury verdict in federal court on behalf of a large consulting firm in a contract dispute.
  • Prevailed in the Southern District of New York on motion to dismiss federal securities law claims against the former officers of a regional telecommunications company.
  • Obtained summary judgment in insurance coverage dispute on behalf of the New Hampshire Insurance Guaranty Association.
  • Prevailed on motion for summary judgment on behalf of regional developer in a matter concerning the validity of a local zoning amendment.
  • Victorious motion for summary judgment in federal court, dismissing claims against public company under guaranty.
  • Contributing Author to Massachusetts Continuing Legal Education’s treatise entitled Damages, Interest and Attorney Fees in Massachusetts Litigation (authored chapter entitled Settlement Evaluation and Negotiation).
  • Apprentice in North Shore Community Mediation Center (NSCMC) (October 2015 – Present).
  • Frequently quoted in Massachusetts Lawyers’ Weekly on commercial litigation decisions.
  • Completed Mediation Training Program Administered by MWI (May 2015).
  • Panelist in numerous MCLE and BBA seminars.

Work Experience

O’Connor, Carnathan and Mack, LLC Partner
Quigley, O’Connor and Carnathan, LLC Partner
Nixon Peabody, LLP
Hutchins, Wheeler & Dittmar, P.C.
Norfolk County District Attorney’s Office Assistant District Attorney



Board of Directors, Affinor Growers, Inc. (Vancouver, BC) (2015-Present)

American Bar Association and Massachusetts Bar Association

City of Beverly Planning Board (2005-Present)

Board of Directors of Camp Bauercrest (2004-2015)

Honors and Awards

  • Martindale Hubbell Distinguished Rating
  • Massachusetts Super Lawyer
    • 2010 to date
  • Voted Massachusetts “Rising Star” attorney
    • 2005


  • J.D., University of Connecticut School of Law
  • A.B., Dartmouth College

Bar Admission

  • Massachusetts