Mark O. Denehy

Mark O. Denehy: Attorney with Adler Pollock & Sheehan P.C.
  • Shareholder at Adler Pollock & Sheehan P.C. (67 Attorneys)
  • One Citizens Plaza, 8th Floor, Providence, RI 02903
    View Mark O. Denehy's office location
  • Peer Reviews
    5.0/5.0 (1)
    Client Reviews
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Trial counsel in noted national Superfund cases and toxic tort and environmental insurance coverage litigation, Mark Denehy has successfully represented manufacturers and others in a wide range of complex, high-stakes product liability matters involving asbestos, Silica, DES, radiation exposure, toxic shock litigation and more.

Author of the Toxic Tort Law Desk Reference’s Rhode Island Section, Mark gives his insurance, Superfund and industrial clients informed, connected and accomplished counsel in critical matters that require regional and national management and coordination.

Mark served as Adler Pollock & Sheehan’s Managing Shareholder from 2003-2012 and has won recognition from his peers and professional organizations for his high ethical and legal standards and performance.

The Latest

•10.18.18 / News

AP&S Attorneys Named 2018 Super Lawyers and Rising Stars

•08.15.18 / News

27 AP&S Attorneys Selected for 2019 Edition of Best Lawyers in America

•08.15.18 / News

7 AP&S Attorneys Named “Lawyer of the Year” from Best Lawyers in America

•10.31.17 / News

AP&S Attorneys Named 2017 Super Lawyers and Rising Stars


Best Lawyers' 2019 Lawyer of the Year, Environmental Law, Providence.
Best Lawyers' 2018 Lawyer of the Year, Mass Tort Litigation / Class Actions - Defendants, Providence.
Best Lawyers' 2016 Lawyer of the Year, Products Liability Litigation - Defendants, Providence.
•AV rated by Martindale-Hubbell, its highest rating for attorneys.
•Selected by his peers for inclusion in the 2007-2019 editions of The Best Lawyers in America in the field of commercial litigation, environmental law and mass tort litigation.
•Recognized in the Chambers USA America’s Leading Business Lawyers in the area of litigation/general and commercial law since 2006.
•Selected as a Rhode Island Super Lawyer, 2007-2018.

In the Community

•Member, Board of Directors of the R.I. Public Expenditure Council.

Seminars / Publications

•Annually Mark authors the Rhode Island Section of the Toxic Tort Law Desk Reference manual, a 50-state compendium of toxic tort laws.

Areas of Practice (6)

  • Litigation
  • Products Liability/Toxic Tort/Mass Torts
  • White Collar Criminal Defense
  • Complex & Business Litigation
  • Insurance Coverage & Defense
  • Environmental

Education & Credentials

Contact Information:
401.274.7200  Phone
401.351.4607  Fax
University Attended:
University of Connecticut, B.A., 1975
Law School Attended:
Suffolk University, J.D., cum laude, 1979
Year of First Admission:
U.S District Court, Eastern and Southern Districts of New York; U.S. District Court, District of Connecticut; U.S. Court of Appeals, First, Third and Fourth Circuits and U.S. Supreme Court; U.S. District Court, District of Massachusetts; U.S. District Court, Western District of Pennsylvania; 1980, Massachusetts and Pennsylvania; U.S. District Court, Western District of South Carolina; U.S. District Court, District of Rhode Island; U.S. District Court, Eastern District of Pennsylvania; 1979, Connecticut; 1986, Rhode Island

Professional Affiliations

•Member, Rhode Island Bar Association Committee on Environmental Law.
•American Bar Association's Torts and Insurance practice section member.
•Member, ABA's section on Natural Resources, Energy and Environmental Law.

Birth Information:
Boston, Massachusetts, 1954
Reported Cases:
Representative Matters: Mark served as trial counsel in Violet v. Picillo, one of the leading Superfund cases in the nation.; He acted as liaison counsel to 130 defendants in the Davis Landfill Superfund case.; He has represented owners, operators, generators, and transporters in numerous Superfund Sites, including; the Cannons Engineering Site (Massachusetts and New Hampshire); the Kingston Steel Drum Site (New Hampshire); the Union Chemical Site (Maine); the Western Sand & Gravel Site (Rhode Island); the BestFoods Site (Rhode Island) and; the Rose Hill Landfill Site (Rhode Island).; Mark has successfully represented numerous industrial clients in litigation against their insurance carriers to obtain coverage for environmental claims.; Mark serves as national coordinating counsel for several clients in toxic tort matters.
Payment Information:

    Peer Reviews

    • 5.0/5.0 (1 review)
    • A Martindale-Hubbell Peer Rating reflects a combination of achieving a Very High General Ethical Standards rating and a Legal Ability numerical rating.
    • Legal Knowledge

    • Analytical Capability

    • Judgment

    • Communication

    • Legal Experience


    *Peer Reviews provided before April 15, 2008 are not displayed.

    Client Reviews

    This attorney does not have client reviews.


    Lex Mundi

    Providence, Rhode Island

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