TITLE: GCN CIRCULAR NUMBER: 33025 SUBJECT: Swift/BAT trigger #1143281 is not a GRB DATE: 22/12/06 17:42:49 GMT FROM: David Palmer at LANL David Palmer, on behalf of the Swift Team, reports: Swift/BAT trigger #1143281, at 2022-12-04 20:45:05 UT, was due to the misidentification of Cyg X-1 during a star tracker Loss of Lock. Therefore, the optical limits reported in GCN #33018 (Lipunov et al.) and GCN #33020 (Odeh) are not relevant to an astrophysical event.