Tech View: Nifty forms bullish piercing candle. What traders should do on Thursday expiry

The short-term trend of Nifty seems to have reversed up, but the uncertainty remains in the market at the highs. The market could encounter strong resistance around 21,500-21,600 levels in the coming session. Immediate support is at 21,220 level, said Nagaraj Shetti of HDFC Securities.