Nearly a third of the revenue generated by the short-term rental company Airbnb in 12 major markets comes from homes and apartments that are rented out on a full-time basis.
That was one of the conclusions of a study commissioned by the American Hotel and Lodging Assn., a trade group for the nation's hotels. The group said the findings point out a "very disturbing trend" that suggest the rentals are operating like "unregulated hotels."
Airbnb called the study deeply flawed.
"This report uses misleading data to make false claims and attack middle class families who share their homes and use the money they earn to pay the bills," the company said in a statement.
The study, which focused on 12 of the nation's largest metropolitan areas -- including Los Angeles, San Diego and San Francisco -- found that 30% of Airbnb's revenue comes from properties that are offered at least 360 days of the year.
The study, completed by a Pennsylvania State University professor with funding from the hotel trade group, also found that 17% of Airbnb landlords in the 12 big metro areas rent out two or more properties.
Katherine Lugar, chief executive of the American Hotel and Lodging Assn., said the findings emphasize the need for cities and states to adopt legislation that imposes the same restrictions on short-term home rentals as on hotels.
"This report shows a troubling trend as a growing number of residential properties are being rented out on a full-time, commercial basis, in what amounts to an illegal hotel, and using Airbnb as a platform for dodging taxes, skirting the law and flouting health and safety standards," she said.
The hotel industry has long been critical of short-term rental companies such as Airbnb, but the study represents the first time the industry has compiled data to support its claims that such businesses operate much like regular hotels without having to meet health and safety standards.
Still, 2015 is expected to have been a record year for hotel occupancy rates and revenues, thanks to increasing demand for lodging and a rebounding economy.
Short-term rental websites such as Airbnb are a relatively new concern for the U.S. hotel industry, which operates about 53,000 hotels and 5 million rooms. Industry leaders have grown increasingly critical of such sites as they have gained popularity. Airbnb now lists more than 2 million properties around the world.
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