News & Events

Stuart H. Sostmann, shareholder and co-chair of Marshall Dennehey’s Construction Injury Litigation Practice Group, has been named Managing Attorney of the the firm’s Pittsburgh office. He inherits the position from Scott G. Dunlop who served in the role for almost 30 years and will retire at the end of the year. Sostmann has served as Assistant Managing Attorney of the Pittsburgh office since 2023.

Marshall Dennehey is proud to highlight the firm’s 109 attorneys who have been recognized in the 2025 editions of The Best Lawyers in America® and the Best Lawyers: Ones to Watch® in America. Less than 6% of all practicing lawyers in the U.S. were selected by their peers for this recognition.

Additionally, five of the firm’s attorneys received the Best Lawyers® 2025 “Lawyer of the Year” awards in their respective practice areas and demographic regions. 

Veteran litigator Matthew K. Flanagan has joined Marshall Dennehey as a Shareholder and Co-Chair of the firm’s Disciplinary Board Representation Practice Group, joining Josh J.T. Byrne in leading the practice. He will divide his time between the firm’s Long Island (Melville) and New York City offices. Previously, he was a Partner at Catalano Gallardo & Petropoulos, LLP in Jericho, NY.  

Teresa O. Sirianni, shareholder in the Professional Liability Department in the Pittsburgh office of Marshall Dennehey, has been elected to membership of the Academy of Trial Lawyers of Allegheny County.

Marshall Dennehey was named the first place winner in the extra-large company category at the Philadelphia Business Journal’s Best Places to Work Awards, held July 25 at Rivers Casino in Philadelphia. The firm has been recognized among the Philadelphia region’s Best Places to Work every year since 2013 and this is the firm’s fourth time winning their company-size category.

A trio of attorneys – two with extensive trial experience in casualty litigation matters – has joined Marshall Dennehey’s Orlando office. Trial attorney Raychel Garcia joins as Shareholder; Brian Catelli as Special Counsel; and Matthew Wykes as Associate. All three previously practiced at Quintairos, Prieto, Wood & Boyer, P.A. in Orlando.