The Foreign Institutional Investors (FIIs) were net sellers to the tune of Rs 527.15 crore in the futures & options segment on Wednesday.According to data released by the NSE, FIIs were net sellers of index futures to the tune of Rs 707.91 crore and bought index options worth Rs 177.41 crore. They were net buyers of stock futures to the tune of Rs 6.51 crore and sold stock options worth Rs 3.16 crore.