There's laws against robbing banks, but people still do it. What laws there are would depend on your state, but even if there is a law, there may be very little penalty. Put yourself in your landlord's shoes for a moment. You have a tenant in the house. You could tell them that the house is in foreclosure, and they move out, or you could keep your mouth shut, keep your tenant, and hence your rental income, and not face much of a penalty if any for failure to say anything. Unfortunately this sort of thing happens quite often. As stated, go check the public records for yourself. Don't depend on the landlord. He/She has a financial interest in you staying in the house as long as possible.