Second bullet: "The aggregate projected loss of the top three concentrated stocks (and their derivatives) will be compared to what would otherwise be the aggregate portfolio margin requirement, and the greater of the two will be the margin requirement for the portfolio."
Does this mean that for an account, with a large position in FFH, margin requirement will be calculated as if it's top 3 positions were zero: at the extreme no margin, if an account has less than 3 positions, or a big reduction of it, by zeroing top 3 positions? Is this normal/common practice by IB?