American Transit, also known as ATIC, insures roughly 60% of New York City’s more than 117,000 commercial taxis, livery cabs, black cars and rideshare vehicles, and has for decades been the dominant player in New York City’s commercial car insurance market, the largest in the country, offering cabbies premiums far lower than other insurers. In the second quarter, it posted more than $700m in net losses, according to a filing with the National Association of Insurance Commissioners.