POxy 1464 (or P. Oxy. XII 1464) is a document that was found at the city of Oxyrhynchus in Egypt. This document was given to a Roman citizen to certify performance of a pagansacrifice, hence demonstrating loyalty to the authorities of the Roman Empire. Such a document is called a libellus (plural libelli), and this was one of four libelli found at Oxyrhynchus.
The manuscript declares the date — the first year of the emperor Decius, whose full name was Gaius Messius Quintus Traianus Decius. We know the first year of his reign was 250 AD. The day and month are also given as the third of Epeiph or Epip in the Coptic calendar. So this libellus was issued on 27 June 250 AD.