53 Pa. Stat. § 30906
After any sale of property or lands for delinquent taxes has been confirmed by the court, as aforesaid, it shall be the duty of the purchaser or purchasers, where the bid exceeds the taxes and costs, as aforesaid, to make and execute to the said treasurer for the use of the persons entitled, a bond for the surplus money that may remain after satisfying and paying all the taxes and costs as aforesaid with warrant of attorney to confess judgment annexed thereto, and it shall be the duty of said treasurer to forthwith file said bond in the office of the prothonotary of the proper county at the number and term where said report and return is filed and the surplus bond filed, as aforesaid, from the time of the date of the deed for property thus sold shall bind, as effectually and in like manner as judgments, the land by said treasurer sold into whose hands or possession soever they may come, and the owner of said lands at the time of sale, their heirs or assigns, or other legal representatives, may, at any time within five years after such sale, cause judgment to be entered in said court upon said bond in the name of said treasurer for the use of said owners, their heirs, assigns or legal representatives, (as the case may be), and in case the moneys mentioned in said bonds, with legal interest thereon from the time it is demanded, be not paid within three months after such entry, execution may forthwith issue for the recovery thereof.
53 P.S. § 30906