TITLE: GCN CIRCULAR NUMBER: 20932 SUBJECT: Fermi GBM Observation of IceCube-170321A DATE: 17/03/22 19:36:34 GMT FROM: C. Michelle Hui at MSFC/Fermi-GBM C. M. Hui (MSFC), A. Goldstein (USRA), E. Burns (UAH), and P. Jenke (UAH) report on behalf of the Fermi GBM team: We have searched the Fermi Gamma-ray Burst Monitor data for a gamma-ray counterpart to IceCube-170321A (Blaufuss 2017, GCN 20929). The position was occulted by the Earth for Fermi at the time the neutrino was detected. GBM therefore cannot set any limits on impulsive emission. Measurements using the Earth Occultation technique around this position place a three sigma flux upper limit of about 230 mCrab between 12 and 100 keV between Mar 18th and Mar 21st.