Singer is also involved in the medical software industry. In 1981, he co-founded Medical Manager, now called Greenway Health, which marketed software that helped medical practitioners manage and digitize their billing records. In 2002, Medical Manager and its subsidiaries were bought by WebMD, in an acquisition valued at roughly $5 billion. Singer continued his work in physician software strategies at WebMD, before resigning in 2005. In 2010, Singer was prosecuted in relation to securities fraud during his time at WebMD, and eventually forfeited $2.5 million in settlements.