TITLE: GCN CIRCULAR NUMBER: 21943 SUBJECT: Fermi Gamma-ray Burst Monitor trigger 528330888/170929011 is not a GRB DATE: 17/09/29 00:54:49 GMT FROM: Rachel Hamburg at UAH R. Hamburg (UAH) reports on behalf of the Fermi GBM Team: The following Fermi Gamma-ray Burst Monitor (GBM) trigger, tentatively classified as a GRB, was in fact likely due to particle activity: 528330888 / 170929011 / 22:34:43.28 UT