As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, CREW REPORTED THE LANDING GEAR WOULD NOT RETRACT. CREW RETURNED TO DEPARTURE FOR AN UNEVENTFUL LANDING. UPON INSPECTED BY MX, IT WAS FOUND THAT THE RT MLG OLEO SEAL HAD ROLLED, PREVENTING THE GEAR FROM FULLY EXTENDING WHICH WOULD NOT ALLOW THE GEAR TO RETRACT.