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.

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, 2012–18
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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: Member, Aviation Law Leadership Committee 
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)