A group called Operation Welcome Home reportedly admits breaking the law.
It took over the home in Madison two weeks ago and changed the locks.
A woman and her children now live there.
The property is scheduled to be sold through a bank sale next week, but the group says the house is already paid for because Bank of America, which owns the mortgage, received billions of dollars in federal bailout money.
Police say they can't get involved unless the owner files a trespassing complaint.