TITLE: GCN CIRCULAR NUMBER: 13978 SUBJECT: GRB 121117A: optical upper limit DATE: 12/11/21 07:21:38 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (SAI MSU, IKI), D.Varda (ISON), E.Sinyakov (ISON), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 121117A (Cummings et al., GCN 13967) with ORI-25 telescope of ISON-Blagoveshensk observatory starting on Nov.17 (UT) 09:05:39. We took several unfiltered exposures within 2 hours after the start. We do not detect the OT (Oates et al., GCN 13973) in the XRT error circle (Beardmore et al. GCN 13972) in any stacked images. A photometry is based on nearby USNO-B1.0 stars (R2): T_start T0+, Filter, exposure, UL (3 sigma) (UT) mid (d) (s) 09:05:39 0.03105 none 80 x 40 18.3 10:05:44 0.07483 none 88 x 40 18.4 09:05:39 0.05397 none 168 x 40 18.9