Biosig, a Canadian-based company, sued Nautilus in August 2004 alleging that various heart rate monitor devices sold by Nautilus with its exercise equipment infringe U.S. Patent Number 5,337,753. Klarquist Sparkman assumed the defense of the case from Ropes Gray in 2008, and promptly moved to put the patent in reexamination. Following the grant of the reexamination request, the parties agreed to dismiss the case without prejudice on March 26, 2009.