Auto stocks hogged the limelight in Monday's session as companies reported strong sales data for July. Mahindra & Mahindra topped the Sensex gainers' chart, soaring 6.15 per cent after the auto major posted a 33 per cent increase in domestic passenger vehicles sales in the previous month. Reliance Industries and Bharti Airtel climbed as much as 2.64 per cent following the culmination of India's biggest ever auction of airwaves, with spectrum worth Rs 1,50,173 crore being sold.