He is the founder, president, board member and, with his family, the largest shareholder of Medallion Financial Corp., an investment company publicly traded on the Nasdaq stock exchange under the symbol MFIN.

[10][19] The company has financed the purchase of thousands more in Newark, Cambridge, Philadelphia, Chicago, Boston and New York City, is an established industry leader.

The subsidiary, eventually named Medallion Taxi Media, was enhanced in 1996 with the acquisition of See Level Advertising.

[26] By December 12, 2017, 9% senior notes issued by Medallion Financial traded for over 100% of par value, which is a significant recovery from distressed levels reached earlier in 2017, and an indication of improved investor confidence.

After a dip at the onset of the COVID-19 pandemic, Medallion Financial's stock price (NASDAQ: MFIN) increased by 5x in the following year.[when?]

[28] In 2008, Murstein along with former baseball player Hank Aaron, former New York Governor Mario Cuomo, both Medallion Financial board members, and former football star and Congressman Jack Kemp, formed a special-purpose acquisition company (SPAC) which raised $230 million to buy a professional sports team.

The team played at Hofstra University on Long Island and won the MLL championship for the third time in 2015.

43 car, becoming the first African-American driver to drive regularly in NASCAR's premier Cup Series in over 40 years.