Аннотация:We present the results of MASTER Global Robotic Net optical observations of LIGO/Virgo S200224ca error-box (O3 set). We observed 380 square degrees inside the 3σ error box during 1 month. We present optical transients found by MASTER auto-detection system during this inspection. They are not the optical counterparts, but the result of MASTER observation strategy, that is is briefly discussed. Also we present short analysis of Swift-UVOT, -XRT transients in MASTER database since 2010.