According to Anand Rathi Securities Nifty futures lost marginal OI. Prices also ended significantly in blue, indicating some amount of fresh buying, along with short covering taking place at current levels.FIIs continue to show some buying. Another short term indicator - Implied Volatility - has shown a sudden spurt, which is natural as we are nearing the end of contract. It also suggests that we might see volatile trading in remaining sessions before expiry. We have to keenly watch Roll Over activity effect before expiry. Lot of fresh positions are being added in some of frontline counters indicating some positive buying.However with expiry coming close and a sudden spurt in volatility, it indicates that the undertone of market is still positive. We might see some volatility before expiry.Technically, one may use the level of 3370 (Nifty) and 10500 (Sensex) as the stop loss level. Nifty faces resistance at 3525 and Sensexat 11850.