It is the first type of regulation of Airbnb for New York City, where an estimated 40,000 hosts list their homes, apartments and spare rooms. Councilwoman Carlina Rivera, a Democrat who sponsored the bill along with 43 other colleagues, said it would give the city the ability to enforce laws that root out "bad actors" who own multiple units that could be used for affordable housing. The measure is designed to help the city recognize who might be warehousing residences. Currently, the only tool they have for enforcement is responding to complaints. Airbnb could face a fine of up to $1,500 for each listing that isn't disclosed to the city, officials said.