Аннотация:MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB201223.75 (trigger No 1014316,08h 51m 23.76s , +71d 10m 26.4s, R=0.05) errorbox 33 sec after notice time and 51 sec after trigger time at 2020-12-23 17:59:18 UT, with upper limit up to 18.6 mag. The observations began at zenith distance = 51 deg. The sun altitude is -40.4 deg. The galactic latitude b = 36 deg., longitude l = 143 deg.Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=1510350We obtain a following upper limits. Tmid-T0 | Site |Filt.| Expt. | Limit| Comment_________|_____________________|_____|_______|______|________ 141 | MASTER-Tavrida | C | 180 | 18.6 | Filter C is a clear (unfiltred) band. The observation and reduction will continue. The message may be cited.https://gcn.gsfc.nasa.gov/gcn3/29156.gcn3