** Shares of RBL Bank RATB.NS gain 4.3% to 261.65 rupees; set for best day since early-July
** Societe Generale SOGN.PA net bought 3.3 million RATB shares for 250.57 rupees apiece via bulk deal, exchange data showed
** About 28.2 million shares traded, 2.3x the 30-day avg
** Stock still down 1.9% so far in August, set to snap five straight months of gains