Mark J. Sullivan


9130 South Dadeland Boulevard Datran Two - Suite 2000 Miami FL 33156





Since 2009 Mark Sullivan’s practice has been devoted primarily to the defense of lawyers at all levels of state and federal courts, and administrative proceedings. Those representations have included professional negligence and breach-of-fiduciary-duty suits, defamation claims, bar grievances, and representations regarding fee disputes, disqualification attempts, and significant sanctions.

Mark’s work for attorneys is not limited to litigation, but also includes prospectively advising attorney clients on ethical issues and general risk mitigation, such as emerging trends in lawyer liability like e-discovery and cyber-liability.

Mark routinely speaks and writes on topics related to lawyer’s liability, and was the one of the primary organizers for all three years of the Florida Lawyers’ Professional Liability Seminar with University of Miami and other Florida firms that focus on lawyer liability. He is active in the national malpractice defense community, and has spoken at the American Bar Association’s national legal-malpractice conference.

Mark earned his Juris Doctor, with honors, from the University of Texas School of Law, and his B.A. in English Literature with minor in Russian Language from the University of Tennessee. While in law school he was an associate editor and notes editor for The Review of Litigation, and was awarded the Dean’s Achievement Award in Mass Media Law.

Mark was also deployed to Guantanamo Bay, Cuba from February to December of 2002 while a reservist in the United States Marine Corps, and previously distinguished himself by graduating first in his class of approximately 200 Marines at the Marine Corps School of Infantry in 1999.

Practice Areas :

  • Professional Liability Defense
  • Defense of Bar Grievances
  • Commercial Litigation
  • Defamation and other Speech-related causes of action
  • Appellate Practice


  • Texas Bar, 2006 (inactive).
  • Florida Bar, 2008.
  • U.S. District Court, Southern District of Florida, 2009.
  • Eleventh Circuit Court of Appeals, 2010.
  • American Bar Association Lawyer Professional Liability section.
  • Association of Professional Responsibility Lawyers.

Education :

  • B.A. English Literature, minor: Russian Language, University of Tennessee, 2001.
  • J.D., with honors, University of Texas School of Law, 2006.

Distinctions  :

  • Dean’s Achievement Award, Mass Media Law, Spring 2004.
  • Company Honor Graduate, USMC School of Infantry, 1999.

Publications :

Speaking engagements:

  • July 2014 – Miami Lakes Bar Association: Legal Malpractice and Ethical Issues (with Alex Diaz).
  • October 2015 – Florida Defense Lawyer’s Association Advanced Litigation Boot Camp: “Staying out of Trouble: Practical Attorney Guidance for Avoiding Civil and Ethical Exposure.” (with Alex Diaz).
  • November 2015 – University of Miami Professional Responsibility & Ethics Program (PREP) clinic with Professor Jan Jacobowitz: Discussion on the relationship between ethical rules and civil liability (with Andrew Feldman).
  • December 2015 — Dade County Bar Association, Young Lawyer Section: “Staying out of Trouble: Practical Attorney Guidance for Avoiding Civil and Ethical Exposure.” (with Alex Diaz).
  • October 2016 – Orlando, FL – FDLA Advanced Litigation Boot Camp: “Retiring with Your Law License” (with Alex Diaz).
  • December 2016 – Miami, FL – GILSBAR Ahead of the Curve series: Ethics of Technological Competency (with Rob Klein).
  • May 2017 – New York, NY – Navigating the Tropics of Bad Faith (with Rob Klein).
  • August 2017  – Miami, FL – University of Miami PREP clinic: Ethical vs. Civil liability (with Florida Bar staff counsel Jennifer Falcone).
  • August 2017 – Ft. Lauderdale, FL – GILSBAR Ahead of the Curve series: Ethics and Civil Exposure for Outsourced Legal Work (with Rob Klein).
  • September 2017 – River Ranch, FL – – Florida Defense Lawyers’ Annual Meeting: Misadventures in Malpractice (with Alex Diaz).
  • October 2017 – Miami, FL – GILSBAR Ahead of the Curve series: Outsourcing, and File Maintenance and Retention (with Alex Diaz).
  • February 15, 2018 – Miami, FL – Desayuno con CABA: Misadventures in Legal Malpractice (with Lelia Schleier).
  • April 26, 2018 – Washington DC – American Bar Association Lawyer Professional Liability National Conference: Greatest Case Law Update Ever!
  • May 17, 2018 – Miami, FL – University of Miami School of Law Legal Malpractice & Professional Liability Roundtable “From Hello to Goodbye.” (“Goodbye” panel with Anthony Alfieri, Deborah Corbishley, Bob Martinez, and Judge Thomas Rebull).

Noteworthy cases :

Reported decisions  :

  • Newman v. Ormond, 456 Fed. Appx. 866 (11th Cir. 2012).
  • Newman v. Ormond, 396 Fed. Appx. 636 (11th Cir. 2010)Newman v. Ormond, 396 Fed. Appx. 636 (11th Cir. 2010).
  • Watson v. Stewart Tilghman Fox & Bianchi, P.A., 4D14-957, 2015 WL 6738760 (Fla. 4th DCA 2015).