TITLE: GCN CIRCULAR NUMBER: 20925 SUBJECT: GRB 170318A: KAIT Optical Upper Limit DATE: 17/03/20 19:32:13 GMT FROM: Max Genecov at UC Berkeley Max Genecov, WeiKang Zhang, and Alex Filippenko (UC Berkeley) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, responded to Swift GRB 170318A (Sbarufatti, et al., GCN 20904) starting at 12:33:14 UT, ~23 minutes after the burst. The target was at low elevation but rising. Observations were performed with an automatic sequence in the clear (roughly R) and I filters, and the exposure time was 20 s per image. We do not detect any optical source within the XRT error circle (Evans, et al., GCN 20907). The limiting magnitude of the co-added clear band image is ~17.6 at a mid-time of 39.7 minutes after the burst.