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CHICAGO — At least 91,000 of Chicago's apartment and condo units, about 7.6 percent of all housing units in Chicago, are on the city's list of places that cannot host guests through home-sharing services like Airbnb.

The city recently made public a list of 940 buildings across Chicago that have submitted documents to the city to formally exclude short-term rentals from their buildings.

The "Prohibited Housing List" was created after last summer's passage of the Shared Housing Ordinance in an attempt to regulate the use of Airbnb in residential neighborhoods.

Many of the buildings are high-rises concentrated Downtown and in surrounding neighborhoods. Several of those buildings are just reinforcing longstanding rules written into building and condo association bylaws prohibiting people from renting out their apartments.

"The decision to place the building on the city’s list was simply to make sure that the firms like Airbnb would know that our building was, for all intents and purposes, to be ineligible for them to accept listings," said Phil Pritzker, general manager of 400 E. Randolph St. At 956 units, his building is the largest building on the list.

"Anyone who would be individually checking to see if they could use the service would also know that the building was off limits," Pritzker added.

The entire home-sharing ordinance was scheduled to go into effect in December, but parts of it have been held up by a pending lawsuit. The ordinance also aims to tax home-sharing hosts.

“We worked diligently in collaboration with city policymakers on clear, fair rules for home sharing in Chicago," Airbnb said in a statement. "We fully understand that home sharing is not a perfect fit for every housing association, and opt-outs are to be expected.”

The company said the number of opt-outs is minuscule compared to Chicago's overall housing supply.

In all, the city has 91,581 housing units on its list of buildings that cannot host home-sharing programs. The U.S. Census Bureau estimates Chicago has about 1.2 million housing units.

What will happen to those who violate the ban on a citywide is unclear. Some building managers said that there would be penalties issued against those who break the rules.

"Any host that lists a unit illegally will be subject to strong enforcement including escalating fines and penalties," said Angel Hawthorne, spokesman for the city's department of Business Affairs and Consumer Protection.

Hawthorne said that the city will work with the company involved in the violation. Anyone who notices a unit that isn't legally allowed to host home-share guests will be able to report violations to 311

Ald. Michele Smith (43rd), who has been the most vocal critic of Airbnb on the City Council, said the size of the list is encouraging, but the process for adding residential buildings that aren't large is too difficult.

Single-family homes and buildings with fewer than five units are not included on the housing list. The ordinance would allow voters to ban or limit home sharing within the borders of their precincts via referendum.

Smith also notes that work remains to be done on the other big list the ordinance calls for: a license and registration list for the places that can be used by Airbnb.

Despite these concerns, Smith said the ordinance is a step in the right direction.

"Chicago, to my knowledge, is the only major city in the world to demand this type of transparency from Airbnb," Smith said. "We have to see how the city follows up on the enforcement. it is a complaint-driven process."

Here's a map of residential buildings that have filed documents with the city to exclude home sharing from their properties:

Source: City of Chicago and Socrata

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