As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE AIRCRAFT RETURNED TO BASE AFTER TAKEOFF BECAUSE THE LANDING GEAR WOULD NOT RETRACT. THE PILOT REPORTED 3 GREEN DOWN AND LOCKED LIGHTS UPON LANDING. SHORTLY AFTER LANDING, THE NOSE GEAR COLLAPSED. INSPECTION SHOWED THE BOLTS THAT HOLD THE NOSE GEAR RETRACT NUT AND TUBE PUSH/PULL HAD FAILED.