Probably related to Bakkt. The interesting thing here is how inexpensive was the transaction fee. How does banks transfer this kind of sum and how much would it cost?
Or, perhaps more similar to the topic, if I wanted to move a billion dollars from one UBS account to a new UBS account, I certainly could. Some special guy would probably have to turn the key for me, but if I have a billion dollars in a UBS account I surely know that man by name. And also, I would have the benefit of doing it privately, unlike with Bitcoin.
It would require an extra pair of eyes compared to a 1M payment (which are very common), but that's not a significant difference in process, just one more employee would have it in their queue for approval and it wouldn't even increase the time as it'd jump to the front of the queue of payments that need some oversight. It could involve some extra notification as $1B leaving or arriving is meaningful enough to impact your liquidity and reserve requirements and thus your trading desk might need to borrow/lend some cash.
I'd assume that a major bank might have $1B+ payments quite often - I mean, the T-bond market alone is $500B daily and probably some of the individual trades are larger than $1B; then every delivery of a $1B+ industrial project is probably accompanied by a similar bulk payment and the projects across all the industries add up.
His son--who only had single-digit millions--wanted to buy a house, so the dad talked to the bank and they arranged a zero-interest mortgage for him. They were happy to pass on what they might have earned from the mortgage interest (a few hundred thousand dollars, I'd guess) to make this guy a happy client.