Stuart H. Sostmann

Co-Chair, Construction Injury Practice Group

    With over two decades of experience as a litigator, Stuart concentrates his practice in the area of commercial general liability. He routinely handles high exposure matters in the fields of product liability, premises liability, auto liability, construction litigation, marine liability, dram shop and commercial litigation. This includes cases involving personal injuries and property damage claims. Additionally, Stuart serves as the firm's casualty supervising attorney in the Pittsburgh office, ensuring that client matters are handled promptly, professionally and effectively.

    In his career, Stuart has represented manufacturers, suppliers and retailers in product liability matters, including electronics, medical equipment, food products, appliances, farm equipment, plumbing equipment, power tools, toys and sports and recreational equipment. He frequently represents property owners, retailers, pharmacies, general contractors, subcontractors and utilities in premises liability litigation. He has tried numerous cases to verdict in counties throughout Western Pennsylvania.

    In addition, a large portion of Stuart’s practice is devoted to construction litigation. These claims are highly involved cases that require deep knowledge and an extensive background in all areas of the construction industry. As co-chair of the Construction Injury Practice Group, Stuart handles a wide variety of construction injury as well as defect cases, defending contractors, subcontractors, material suppliers, engineers, architects, and other construction trade professionals throughout the State of Pennsylvania against such claims. The scope of his representation includes common claims of construction defect issues like water intrusion due to faulty roofing or window/door seals, cracked foundation or improper water proofing, structural issues, design issues, mold intrusion, drywall problems, and soil subsidence, heaving or movement.

    Stuart attended the University of Pittsburgh graduating with a B.A. in Political Science. He then attended the University of Pittsburgh School of Law where he participated in the Appellate Moot Court Program, Student Bar Association and the Health Law Certificate Program. He obtained his juris doctor from the University of Pittsburgh School of Law.

    Stuart is the current President of the Pennsylvania Defense Institute, the state’s leading organization devoted to improving the administration of justice and educating those who defend clients in civil cases. He is also a member of the Allegheny County Bar Association and the Academy of Trial Lawyers of Allegheny County. Among his many honors, he is Rated  AV® Preeminent™ by LexisNexis Martindale-Hubbell and is recognized among the Best Lawyers in America for his work in product liability litigation. Stuart is additionally recognized as Pennsylvania Super Lawyer.

    Significant Representative Matters

    Successfully argued a precedent-setting case in the Pennsylvania Superior Court where a waiver of subrogation clause in a construction contract was applied to building damages caused by a windstorm three years after the project was completed. 

    Successfully defended a product installer at trial in a single vehicle accident, where the placement of the product in the vehicle was claimed to be the cause of the crash at high speed.  A defense verdict was obtained after a 5 day jury trial where the demand was $800,000 prior to trial.

    Classes/Seminars Taught

    Civil Litigation State of Affairs – The Impact of COVID-19 in Pennsylvania and New Jersey & What’s Next, Marshall Dennehey Client Webinar, May, 2021

    An Overview of Construction Defect Litigation in Pennsylvania, Nationwide Insurance Company, December 16, 2014

    Commercial Defense Practice in New York, New Jersey & Pennsylvania, Nationwide Insurance Company, December 5, 2014

    Brief Overview of Pennsylvania Contractual Indemnity and Additional Insured Issues, Nationwide Insurance Company, April 2012

    Discoverability and Proper Use of Claim Notes, Berkley Mid-Atlantic, October 2011

    Published Works

    “Yes! Waivers of Liability for Recreational Activities Are Still Effective in Pennsylvania,” Defense Digest, Vol. 23, No. 1, March 2017

    "Timing Is Everything, Even for Bad Faith Claims," Defense Digest, Vol. 6, No. 1, February 2000 

    Supreme Court of the United States
    University of Pittsburgh School of Law (J.D., 1999)
    University of Pittsburgh (B.A., cum laude, 1996)
    Honors & awards
    The Best Lawyers in America©, Product Liability Litigation - Defendants
    Pennsylvania Super Lawyers
    Associations & memberships
    Allegheny County Bar Association
    American Bar Association
    Pennsylvania Defense Institute, President 2022-2023; Executive VP of Operations 2021-2022; Executive VP of Programming 2020-2021
    Year joined