As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOS FLT 721 FCO TO CLT. THE NUMBER ONE ENGINE BEGAN TO HAVE LOSS OF OIL. THE CREW VERIFIED THAT IT WAS NOT AN INDICATION PROBLEM. THE FLIGHT DIVERTED INTO BOS WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND THE NUMBER ONE ENGINE OIL FILTER HOUSING RUNNING OIL LEAK DUE TO A CRUSHED O-RING. REMOVED AND REPLACED THE NUMBER ONE ENGINE OIL FILTER AND O-RING, AND REPLENISHED OIL AS REQUIRED. LEAK CHECKED GOOD.