Domestic stock markets started Friday's session on negative notes amid weak global cues. The S&P BSE Sensex opened at 36,449.27 and the Nifty50 barometer of the National Stock Exchange (NSE) started at 10,944.25. In the first few minutes of trade, the 30-share Sensex traded at 36,389.19, down 42.48 points or 0.12 per cent, and the Nifty50 was at 10,937.75, with a loss of 13.95 points or 0.13 per cent.