TITLE: GCN CIRCULAR NUMBER: 17730 SUBJECT: GRB 150423A: KAIT Optical Upper Limit DATE: 15/04/23 07:45:42 GMT FROM: Weikang Zheng at UC Berkeley WeiKang Zheng and Alexei V. 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 150423A (Pagani et al., GCN 17728) starting at 06:30:00 UT, 116 s after the burst, under thin-cloudy condition. Observations were performed with an automatic sequence in the clear (roughly R), V, and I filters, and the exposure time was 20 s per image. We do not detect the optical source reported by Varela et al. (GCN 17729), in our images, nor any other new source within the XRT error circle. The typical limiting magnitude of our single clear image is about 17.0 calibrated to USNO B1.0.