In 1768, as an antiguo poblador, Juan Antonio Leal was granted Mier 55 by the King of Spain. Juan Antonio Leal was not on Mier roster believing he was a resident of Revilla, but the tract assigned to him.

Juan Pantaleon Izaguirre owned Mier 55 by purchase. Seabury papers contain an abstract of title for this tract associated with J P Izaguirre. When/if this tranfer took place is not certain. In 1787 there was a ranch occupied by the original grantee's daughter Josefa Leal and her husband Antonio Ramirez, but by 1791 they had moved to Rancho Miguel Perez on the San Juan River.

In 1852 Francisco Izaguirre applied for confirmation of Mier 55 from the State of Texas. Francisco Izaguirre was Juan Pantaleon Izaguirre's grandson.