According to a report in the New York Post, a sea change in the taxi business has blindsided one of the industry's most powerful players. Evgeny "Gene" Friedman built an empire on taxi medallions, the gold badges issued by the city which are required to operate a yellow cab. Now he is accused by his creditors of falling behind on tens of millions in loans.

Even as the population grew, the number of New York City taxi medallions remained fairly limited, and their price had risen for decades, soaring over 1000 percent since 1980, and peaking at over 1 million apiece in early 2013. They were long touted as a brilliant investment. But that trend reversed in the fall of 2014, and prices have been sliding since. According to the New York Post report, Citibank is now taking Friedman to court, seeking to foreclose on 90 of his medallions to cover $31.5 million in unpaid loans.

Taxi medallion prices rose steadily for over 30 years, but have recently declined

Friedman made his money leasing the medallions to drivers. Back in 2013 he was fined more than a million dollars for overcharging drivers desperate to gain access to taxis. But as the options for these workers expanded with the growth of Uber, Lyft, and other ride-hailing apps, drivers weren't willing to pay as much for that privilege.

In a statement Friedman and his lawyers tried to position this as a story about a bank that had gotten cold feet. "Change has been very good for the taxicab industry, yet mega-banks like Citibank have been unable to move quick enough and adjust to that change when it comes to this industry," read the statement. "One wonders, if Uber is worth $44 billion, how much is Mr. Freidman’s fleet worth if he has thousands of cabs and drivers nationwide? It surely does not create billions to create an app."