TITLE: GCN CIRCULAR NUMBER: 7408 SUBJECT: GRB 080307: GAO 150cm telescope Optical Observation DATE: 08/03/11 11:21:49 GMT FROM: Kenzo Kinugasa at Gunma Astro. Obs/Japan K. Kinugasa, S.Honda, O.Hashimoto, H.Taguchi (Gunma Astronomical Observatory) report: The field of GRB 080307 (Holland et al. GCN 7362) was observed with the 150 cm telescope of the Gunma Astronomical Observatory. Starting at 13:06 UT (1.67 hours after the burst), Rc, Ic, and V frames were acquired for 3 x 5-min, 6 x 5-min, and 2 x 5-min exposures, respectively. We do not identified the optical counterpart reported by Tanvir et al. (GCN 7369) to 3-sigma limiting magnitudes of Rc=21.5 and Ic=21.0 relative to USNO-B1.0 magnitudes.