The concept of All Appropriate Inquiry is not new. It is rooted in the Innocent Landowner Defense of the original CERCLA statutes discussed in the previous chapters of this manual The statute states: 9601 (35)B To establish that the defendant had no reason to know, as provided (above), the defendant must have undertaken at the time of acquisition all appropriate inquiry into the previous ownership and uses of the property consistent with good commercial or customary practice.