As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SFO - CREW REPORTED RIGHT ENGINE OIL PRESSURE LIGHT DROPPED TO 20 PSI AND STABILIZED. RIGHT HAND THROTTLE REDUCED TO IDLE. FLIGHT RETURNED SFO LANDED WITHOUT INCIDENT. FOUND OIL LEAK AT 11 O`CLOCK POSITION. REMOVED AND REPLACED OIL TUBE AT OIL FILTER DIFFERENTIAL PRESSURE SWITCH. SYSTEM GROUND CHECKED NORMAL OPERATION.