cdu shorting activity, page-443

My head's spinning a bit with all those A's and B's max, but I'll just sort out the first one:

"Assume Institution "A" lends shares to Institution "B" for short selling purposes but Institution "A" also buys the shares sold short by "B", (or for that matter "A" could be buying the shares being short sold by other Institutions also involved in borrowing/lending). That particular scenario would explain why Institution A's holding doesn't change significantly after settlements are effected. i.e. The shares borrowed from "A" would flow out of their account but other shares purchased (e.g. the short shares by "B") would also flow back into their account"

That's not true. Lets say A has 15% of CDU. If they lend out stock, they still have a reportable interest in CDU. If they buy another 5% of CDU (whether the stock they lent out or not is irrelevant), they'd have to report a 20% holding. Companies don't report just the physical stock they hold, but the relevant interest they hold.