I don’t think he has it on Coinbase, prob some sort of multi-sig.
Discussion
yeah i'm pretty sure microstrategy has in-house/contracted providers for this
They started to self custody some portion, but in the beginning I believe they had a significant portion on Coinbase. I would think he has a few different setups, institutional custodianship being one of them.
Are those his bitcoins? Even if he has the PKs, once that are declared and in compliance, Are they really his?
When your PKs are only one warrant away and the State knows about your stash, how long till it isn't yours anymore?