16 Pa. Stat. § 5234
Immediately after the adoption of any zoning ordinance or amendment by the county commissioners, the county zoning commission shall prepare and publish a complete list of all nonconforming uses and occupations existing at the time of the adoption of such ordinance or amendment. Such list shall contain the names and addresses of the owner or owners of such nonconforming use and of any occupant other than the owner, the legal description or descriptions of the land, and the nature and extent of land use.
After any necessary corrections have been made under a procedure prescribed by the county commissioners, copies of such list shall, when approved by such body, be filed for record in the offices of the recorder of deeds and of the chief clerk in the county in which the lands are situated, and shall be corrected yearly, as the county commissioners may prescribe.
16 P.S. § 5234