SKYWATCH INCIDENT REPORT PRIMARY CODE: UNIDENTIFIED AERIAL PHENOMENON Date: 09:25 10/04/2023 Callsign: UAL476 Origin: SFO Status: Closed Aircraft: B739 Destination: ORD POD: DEN Tail Number: New Destination: Reporting Facility: ZDV Operator: UAL Operator Type: Commercial Paged: YES MOR Init: YES MOR ID: ZDV-M-2023/10/04-0001 REMARKS Aircraft reported an unidentified aerial phenomenon off the left side at FL350, 42 NM NE of BFF. The unknown phenomenon was three bright white lights, not moving or changing altitude, blinking left to right and right to left. SKYWATCH INCIDENT REPORT | DATE: 2023-10-04T09:25 | POD: DEN | PAGE 1 of 1