According to the study, a property becomes a “zombie” when a bank files for foreclosure but does not actually take ownership for more than three years. Many homeowners are either left unaware that they still hold title to the property or have moved out of the area, under the impression that they can no longer legally live there.

The study examines the extent of the foreclosure crisis that hit Chicago from 2008 to 2012, which resulted in more than 217,035 foreclosures.

Researchers found 60 percent of foreclosures filed from 2008 to 2009 remained unsold by 2012. Eighteen percent of them are now considered “zombie properties.”

While properties sit in foreclosure limbo, it is unclear who actually owns them and is responsible for maintaining them. As a result, zombie properties often remain vacant and neglected for years.

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