Selling pressure was seen in oil and gas, healthcare and IT sectors, while marginal good buying was observed in auto sector.
The 30-scrip Sensitive Index (Sensex) of the S&P Bombay Stock Exchange (BSE), which opened at 27,530.26 points, was trading at 27,404.61 points (at 12.21 p.m.), down 101.85 points or 0.37 percent from the previous day's close at 27,506.46 points.
The Sensex has touched a high of 27,571.25 points and a low of 27,342.80 points in the trade so far.
The S&P oil and gas index dropped by 78.28 points, healthcare index went down by 68.52 points and IT index slipped by 47.63 points.
However, auto index inched up by 44.01 points.
The wider 50-scrip Nifty of the National Stock Exchange (NSE) was also trading 29.25 points or 0.35 percent down at 8,237.75 points.