The purchaser ought to have been made a party to this suit in view of the reliefs of the plaintiff to declare the sale null and void and consequently to set it aside. Any order made in favour of the plaintiff will adversely affect the purchaser. It is also pertinent that where there is prayer to set aside an auction sale, the court must remember that it is settled law that a mortgagee is not a trustee of a power of sale for the mortgagor except for the balance of the purchase money. It is a power given to him for his own benefit, enabling him to protect the mortgage debt. A purchaser who bought a property sold by a legal mortgage in exercise of his power of sale under a mortgage upon a default and repayment of a loan by the mortgagor is not a trespasser. All State Trust Bank v. Nsofor (2004) All FWLR Pt. 201, Pg. 7719 Union Bank of Nigeria v. Ozigi (1991) 2 NWLR Pt. 176, Pg. 677.
— O.O. Adekeye, JSC. Agboola v UBA (2011) – SC.86/2003