As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED LANDING GEAR WOULDN'T RETRACT AFTER TAKEOFF FROM PHL, DECLARED EMERGENCY AND RETURNED TO PHL WITHOUT INCIDENT. MAINTENANCE REMOVED AND REPLACED THE LANDING GEAR HANDLE AND CYCLED THE GEAR PER EMB AMM, A/C WAS THEN RETURNED TO SERVICE.