Here's what we know so far about Friday’s margin call

Shares of ViacomCBS and Discovery both rebounded after coming under intense selling pressure last week. The two companies were believed to be hit by forced liquidation of positions held by the multibillion dollar family office Archegos Capital Management, a source familiar with the situation told CNBC. CNBC's Jim Cramer, Carl Quintanilla and David Faber discuss.
Mon, Mar 29 202110:17 AM EDT