It's only (potential) fraud if he doesn't disclose his stake as a potential conflict of interest.
I'm not suggesting that Twitter investing in BTC is or isn't a good thing, but the CEO having a personal stake should not prevent the company from investing if there's suitable expectation of positive returns for the business.
Sounds a little dramatic (especially since 50 million isnt moving the price single handedly). Also stock buybacks are essentially the same thing (if you were to call it a conflict of interest) and almost every company in existence does that.
You just talked about Twitter buying BTC as important news showing it's viability though... It's mostly a popularity/buzz game.
Also yeah, stock buybacks were illegal up until 1982 and since there legalization we've seen large trades in companies from R&D spending towards buyback spending...
I mentioned several noteworthy people and institutions making an investment to demonstrate a trend. "its mostly a popularity/buzz game" yeah thats how value networks work. From gold to cash to facebook.
