Real estate experts speaking to The Wall Street Journal say the suit is the first of its kind by a major landlord, opening a thorny new front in the booking platform’s ongoing regulatory and legal struggles. So far, Airbnb has primarily clashed with city leaders, with New York, San Francisco, and Berlin imposing or strengthening restrictions on short-term rentals. Cities have primarily argued that Airbnb raises residential rental prices in overcrowded cities.

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AIMCO is now further claiming that Airbnb encourages its tenants to break their lease conditions, which prohibit renters from offering short-term subleases. AIMCO further claims Airbnb guests have caused property damage to buildings and, as AIMCO’s CEO wrote in a statement, created “disrespectful and unsafe conditions” for residents.

The company further described Airbnb guests as “trespassers, with unvetted personal histories, and no vested interest in maintaining a peaceful community atmosphere.” They allege Airbnb guests have been involved in “incidents of public drunkenness and fighting requiring police assistance.”

An Airbnb spokesman quoted by the Journal described the suit as an “attack on the middle class by powerful interests”, echoing the company’s frequent argument that Airbnb offers a financial boost for working families. However, many Airbnb listings are operated by full-timers and investors who buy multiple apartments specifically for short-term rentals.

If the AIMCO suit is successful, it could encourage other landlords to follow suit, since the majority of lease agreements, whether with corporate or small owners, include prohibitions against subleasing.

AIMCO operates in 23 states and houses 250,000 residents, according to the company.