The Foreign Institutional Investors (FIIs) were net sellers to the tune of Rs 1,305.19 crore in the futures & option segment on Monday.According to data released by the NSE, FIIs were net sellers of index futures to the tune of Rs 1,624.19 crore and sold index options worth Rs 55.15 crore. They were net buyers of stock futures to the tune of Rs 394.88 crore and sold stock options worth Rs 20.73 crore.