(CN) – A California man sued the founder of home security company Ring in state court Friday, alleging that Jamie Siminoff, whose company was featured on the TV show “Shark Tank,” bilked him out of $300 million.

Russell Stephens, a Silicon Valley entrepreneur, said he was an early adviser to Siminoff and invested more than $100,000 into the company in exchange for stock after Siminoff failed to secure an investor on the popular TV show in 2013.