The domestic markets have started the last trading day of the week on a positive note, continuing with the gains witnessed in the previous session. At 9:20 am, the BSE Sensex was trading at 52,823.77, higher by 131.77 points or 0.23 per cent and the NSE Nifty was at 15,827.30, up 35.95 points or 0.21 per cent. The broader markets are trading firm, with the BSE Midcap index and BSE Smallcap index adding 0.5 per cent and 0.3 per cent respectively.