Jonathan Ziss is a partner in Goldberg Segalla’s Philadelphia office. He chairs the firm’s Management and Professional Liability Practice Group, chairs the firm’s Aviation Litigation Practice Group, and is a member of its Commercial Litigation and Cybersecurity Practice Groups.

Jonathan devotes much of his practice to the representation of professionals, including accountants, attorneys, bankers, design professionals, insurance agents/brokers, directors and officers, and fiduciaries, in administrative and civil proceedings. He counsels and defends not-for-profit entities including homeowners' associations, faith-based organizations, and others, in management liability litigation as well as non-litigated disputes. Jonathan also counsels clients and litigates, arbitrates, and mediates commercial disputes in a wide range of industries, from healthcare to hospitality. In addition, as a member of the firm's cyber incident response team, he manages compliance and loss mitigation campaigns in the aftermath of data breaches.

Jonathan has represented many local, regional, and national accounting firms in a wide variety of matters and in a number of forums, including all forms of ADR. In professional negligence matters, he has represented accountants in lawsuits brought by former clients; by purchasers or sellers in disputes arising out of business combinations; by factors, banks, and other lenders; by creditors in bankruptcy and bankruptcy trustees; and by other affiliated professionals. In addition, Jonathan is frequently called upon to represent accountants in investigations by federal, state, and local authorities, including the Internal Revenue Service, the FBI, and the Department of Labor, as well as investigations by bankruptcy trustees and creditors’ committees. He has worked with accounting firms preparing for grand jury appearances.

Jonathan has also represented lawyers and law firms in professional negligence matters, including one matter involving an alleged staged motor vehicle accident ring, for which a federal grand jury had been convened. He is also hired by law firm managing partners to handle their firm's business and employment-related litigation.

In the field of aviation litigation, Jonathan has represented regional, national, and international air carriers, as well as under wing service providers, municipal authorities, general aviation owners and pilots, and fixed base operators, in connection with property and casualty liability litigation. He also acts as coverage counsel. In addition to handling disputed matters, he counsels commercial airlines in connection with industry-related consumer compliance and contractual matters. Jonathan’s transportation litigation experience also includes handling high-profile cases for the Southeastern Pennsylvania Transportation Authority (SEPTA) involving rail and bus accidents. In addition, he has handled recreational boating and trucking claims.

Jonathan is a former chair of the CLM’s Professional Liability Committee as well as the immediate-past President of the Professional Liability Defense Federation (PLDF), and he is also a past chair of the Professional Liability Underwriting Society (PLUS) Mid-Atlantic Steering Committee. Jonathan is a frequent author and lecturer on the subject of professional standards, professional liability risk, and aviation liability. He has been quoted in, Dow Jones News Service, Law360, The Legal Intelligencer, and Reuters, among others.

  • AV Preeminent Peer-Review Rating; Philadelphia's Top-Rated Lawyers, 2017 (Martindale-Hubbell)
  • Pennsylvania Super Lawyers, Professional Liability: Defense, 2012–19
  • View peer-review methodologies at and No aspect of this advertisement has been approved by the Supreme Court of New Jersey. 
Professional Affiliations
  • American Bar Association: Member, Tort and Insurance Practice Section, Aviation Litigation Committee
  • Professional Liability Defense Federation (PLDF): Immediate-Past President
  • Professional Liability Underwriting Society (PLUS): Past Chair, PLUS Mid-Atlantic Steering Committee
  • Claims and Litigation Management Alliance (CLM): Former Chair, Professional Liability Committee
  • Defense Research Institute (DRI): Member, Aviation Law Leadership Committee 
  • Aviation Insurance Association
Admitted to Practice
  • Pennsylvania
  • New Jersey 
  • U.S. District Courts for the Eastern and Middle Districts of Pennsylvania
  • U.S. District Court for the District of New Jersey
  • U.S. Court of Appeals for the Third Circuit
  • U.S. Tax Court
  • Villanova University School of Law, J.D., 1984 (Staff Member, Villanova Law Review)
  • Franklin and Marshall College, B.A., cum laude, 1981 (Elected Phi Beta Kappa)
  • "Professional Liability Risk Management for Tax Preparers," PA Society of Tax and Accounting Professionals Tax Potpourri Seminar, Springfield, PA, February 1, 2019
  • "Taming the Beast — Best Practices When Defending a Not-For-Profit Board," PLPF Annual Meeting, New Orleans, LA, October 3, 2018
  • "Airline Passenger Rights (and Wrongs) in the Age of Expulsion," Lawline Webinar, New York, NY, November 10, 2017
  • "Cyber Attacks: Protecting Your Practice on the New Frontier of Professional Risk," King of Prussia, PA, November 2, 2017
  • "Accountants' / Tax Preparers' Exposure to Cyber Risk (Including Identity Theft) — Defending Best Practices and Compliance," CLM Webinar, October 26, 2017
  • "Litigating the Unruly or Disruptive Passenger Lawsuit – Strategies and Tactics," Air Law Symposium, Irving, Texas, March 31, 2017
  • "The Dawn of the Drone Age — Part 2: Emerging Developments in the UAS Insurance Market and Where Drone Insurance Underwriting Stands Today,"  American Conference Institute's 8th National Forum on Aviation Claims & Litigation, New York, NY, June 27, 2016
  • "The Impact of Aging on Professional Liability Claims," 10th Annual Errors & Omissions Insurance ExecuSummit, Uncasville, CT, June 7, 2016
  • "The Intersection of Social Media and Medicine, and the Latest Implications of Online Communication Between Doctor and Patient," ACI Medical Liability Conference, New York, NY, October 26, 2015
  • Panelist, "Drones in the Construction Industry: Regulatory Compliance and Risk Mitigation," Associated General Contractors of America IT Forum, Chicago, July 30, 2015
  • "Claims and Litigation," ACI's Claims and Litigation Conference, New York, NY, June1, 2015
  • "MedPL: Mo' Money, Mo' Problems: Do Limits Increase Claims Values?," 2015 Medical PL Symposium, Atlanta, GA, April 29, 2015
  • Panelist, "Hot Data Breach Litigation Issues," 4th Annual National Cyber Liabilities Insurance ExecuSummit, Uncasville, CT, April 21, 2015