Could be, but is not mentioned in the offer. Also maybe most of those shares are also already offered as collateral for something else.
His NW went from 20B to 270B in last 2 years.
If your house went from 200k to 2.7M, the bank will somehow find it in their heart to lend you a lot more dollas than before ¯\_(ツ)_/¯
Doing the actual maths 40B is chump change and he could probably borrow couple hundred B or more if the things he's buying also have market value banks will lend on.
Unless he's somehow borrowed hundreds of Bills in the last 2 years? Any sources for that, I looked because of what you said but didn't see any actual info on loans beyond .5B in 2020 which is a fifth of a percent of his NW. Literally < 1% of his NW ??
https://www.morganstanley.com/content/dam/msdotcom/en/about-...