Announcements
Sidley Represents Fitness Industry Veteran Mark Mastrov in Acquisition of 24 Hour Fitness
January 12, 2026
Sidley represented Mark Mastrov and his affiliated investment entities in the strategic acquisition of 24 Hour Fitness, partnering with LongRange Capital to bring the iconic fitness brand’s founder back into an ownership and leadership role. More information on the transaction can be found here.
The Sidley team was led by Michael Podolny (Emerging Companies and Venture Capital) and Mark Castiglia (Private Equity); and included Vadim Brusser (Antitrust and Competition); Nicholas Frey (Employee Benefits and Executive Compensation); Eric Kauffman (Labor, Employment and Immigration); and Thomas Guzman (M&A).
The Sidley team was led by Michael Podolny (Emerging Companies and Venture Capital) and Mark Castiglia (Private Equity); and included Vadim Brusser (Antitrust and Competition); Nicholas Frey (Employee Benefits and Executive Compensation); Eric Kauffman (Labor, Employment and Immigration); and Thomas Guzman (M&A).
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