Heyl Royster


Mark McClenathan

Mark McClenathan

Significant Cases

  • Represented a restaurant and bar at trial in a wrongful death lawsuit in Winnebago County, IL involving the shooting of the plaintiff decedent. Obtained summary judgment on the Dram Shop counts before trial, and obtained a defense verdict on the remaining negligence counts at trial.
  • Represented a trucking company at trial in a wrongful death lawsuit in LaSalle County, IL where the plaintiff claimed violations of numerous federal and state trucking regulations. At trial, Mark obtained a defense verdict.
  • Defended and obtained dismissal of a federal lawsuit filed against the designer and builder of an ethanol plant in which the owner claimed lost income and production resulting from several fires at the plant.
  • Represented civil engineers and highway construction contractors in defense of complex claims relating to road construction design, construction supervision,  and alleged road defects (such as failed concrete, pavement markings, construction signage), leading to personal injuries and wrongful death claims. Mark obtained dismissal of all claims.
  • Defended a complex claim, including claims for injunctive relief and breach of contract, brought by an Illinois municipality against its cable franchisee for alleged violations of a Franchise Agreement, including litigation over the interpretation of the amended Illinois Cable and Video Customer Protection Law, 220 ILCS 5/22-501(b)(3) and related municipal regulations.
  • Defended and obtained dismissal of a federal claim against a farm service for negligently spraying a farmer's corn crop with a herbicide in violation of federal statues, rules and regulations, and allegedly destroying his corn crop.
  • Defended and obtained dismissal of two separate preferential treatment claims in the U.S. Bankruptcy Court against creditors of companies filing for bankruptcy, and successfully prosecuted a Section 523 Complaint to Determine the Dischargeability of a Debt in a construction case.


  • Assisted various municipalities on incorporations; drafting new or amending existing zoning, subdivision, and general ordinances; drafting comprehensive plans; negotiating and drafting border agreements and annexation agreements.
  • Represented municipalities in court on border disputes.
  • Represented municipalities before administrative boards on disciplinary proceedings (including police issues).
  • Represented Ken Rock Community Center on sale of commercial/school property.


  • “Crossing the Line: Interference with Business and Contractual Relations,” Illinois Defense Counsel Quarterly Monograph (2017) - Download Article
  • "Proposed Law Would Not Allow Counties to Set Standards for Wind-Farms," Heyl Royster Governmental Practice Client Alert (2014) - Read Article
  • "Sale of Goods - Disclaiming of Warranties and Consequential Damages," Heyl Royster Business & Commercial Litigation Newsletter (2014) - Read Article
  • "Municipal Bankruptcy - Can an Illinois Municipality File for Bankruptcy Protection?," Heyl Royster Governmental Newsletter (2014) - Read Article
  • "Protect Your Business - The Three Component Test For Restrictive Covenants In Employment Contracts," Heyl Royster Business & Commercial Litigation Newsletter (2013) - Read Article
  • "The Effect of The Illinois Firearm Concealed Carry Act on Municipalities" (2013) - Download Article

Public Speaking

  • “Risk Transfer in Contracts ‘Key Provisions and Remedies You Must Have’”
    Heyl Royster “Avoiding Litigation Part Deux” Seminar 2018
  • “Liability Protection: ‘How to Prevent the Piercing of the Corporate Veil’”
    Heyl Royster “Avoiding Litigation Part Deux” Seminar 2018
  • “CyberLiability for Park Districts: How to Build Your Defenses for a Cyber Attack”
    IAPD and IPRA Soaring to New Heights Annual Conference 2018
  • “Cyber Liability”
    Heyl Royster Governmental Seminar 2017
  • “Best Practices for Minimizing Cyber Liability”
    Illinois Association of Park Districts Legal Symposium 2017
  • “We Need a New Stadium – If You Build It, Suits Will Come: Construction Coverage Issues”
    Heyl Royster's 32nd Annual Claims Handling Seminar 2017
  • “Get Organized”
    Heyl Royster Governmental Seminar 2016
  • “Liability Protection: How to Prevent the Piercing of the Corporate Veil”
    Northern Illinois Builders Contractors Association (NIBCA) 2016
  • “Preserving Electronic Information: Protect your business in the event of a lawsuit or the threat of a lawsuit.”
    Heyl Royster “Avoiding Litigation” Seminar (Urbana, IL) 2016
  • “Staying Out of Litigation: When to Require Liability Waivers”
    IAPD/IPRA "Soaring to New Heights" Conference 2016
  • “Alternative Dispute Resolution – 'Using mediation or arbitration early to avoid lawsuits later.'”
    Heyl Royster “Avoiding Litigation” Seminar, Rockford and Peoria 2016
  • “Vicarious Liability – 'Why Should I Care?'”
    Heyl Royster 'Avoiding Litigation” Seminar, Rockford and Peoria 2016
  • “Concealed Carry: Illinois Law in Review”
    Heyl Royster's 30th Annual Claims Handling Seminar 2015
  • “Discrimination and Retaliation (Civil Rights Act, ADEA, ADA, and other)”
    Recent Legal Decisions Affecting Businesses & Employers, Heyl Royster Seminar 2015
  • “Staying Out of Litigation: When to Require Liability Waivers”
    IAPD/IPRA “Soaring to New Heights” Conference 2015
  • “New Concealed Carry Law Considerations for Employers”
    Illinois Defense Counsel Seminar, Chicago 2014
  • “How to Use Technology Advancements in Construction Litigation”
    Illinois Association of Defense Counsel and the Illinois Insurance Association Spring Symposium 2014
  • “Medical Cannabis: A Primer For Employers and Governmental Entities”
    Heyl Royster Lunch & Learn Seminar/Webinar 2014
  • “Building Your Community's Future: Best Practices for Local Government Construction Projects”
  • “Uninsured and Underinsured Arbitration”
    ISBA Insurance Section, Chicago 2011
  • “Uninsured and Underinsured Motorist Law Update”
    Heyl Royster Claims Seminar 2010 and 2011
  • “Evidentiary Issues for the Claims Professional”
    Heyl Royster Claims Seminar 2008
  • “Premises Liability Update”
    Heyl Royster Claims Seminar 2007
  • “Mediation and Arbitration: When, Why & How?”
    Heyl Royster 2001
  • “Various presentations to local realtor company meetings on professional liability issues”
  • “Evidentiary Issues for the Fire Investigator”
    Northern Illinois Arson Investigator Association annual certification meetings