The Sensex crossed the 50,000 mark on Thursday due to better-than-expected quarterly results from Indian companies and increased foreign investment. Meanwhile, Nifty has also surpassed the 14,700-mark with a jump of 86 points. Market regulator SEBI on Wednesday approved Reliance Industries to buy Future Group estates, a deal worth Rs 24,713 crore, following which the Sensex witnessed a jump on Thursday.