Foreign institutional investors (FIIs) were net buyers of Rs 778.20 crore on Monday, November 13, according to data released by Sebi today.While FIIs made gross purchases of Rs 1,927.70 crore, gross sales totalled Rs 1,149.50 crore.Mutual funds (MFs) were net buyers of Rs 52.01 crore on Monday. MFs made purchases of Rs 549.28 crore and sales of Rs 497.27 crore.