Yeah it would have to be something like that. It seems a too obvious of a move, so I figured he might have had a solid loophole.
To wit: Bill Gates did a bunch of press before starting his foundation to make it clear that him selling MS shares was not about concerns over MS’s future but that he needed a shitload of money for other pursuits.
And Warren Buffet would use many frontmen to slowly buy shares without triggering a buying frenzy. You can’t just buy or sell 3% of a company without causing drama.