They may very well have bought it. My point is that the use of "transferred" make it not clear either way. I must have skimmed through a dozen articles so far that report it as a 'buy' but they all seem to originate from the same "transferred" source tweet that you and I are referring to, with no indication that they have any further information than what you and I have. I'm not saying I necessarily think one way or the other... it just strikes me as odd as worded, and I'm happy to wait for explicit confirmation.
BTW, I think they MUST be holding Bitcoin elsewhere. They have made it transparent some time back that they would purchase 1 BTC every day, and the address they have made public reflects almost EXACTLY 1 BTC every day. They supposedly have additional BTC revenue however: perhaps most notably, from mining. When they first established their transparent BTC address, they announced a bunch of the initial balance was from mining BTC... clearly they MUST have been able to mine some more since then. If their transparent public address is only showing the 1 BTC daily purchase, then they MUST be keeping the mined BTC somewhere else. (BTW, I'm conceding that maybe no one is dumb enough to pay their taxes in BTC, but that would be another potential BTC revenue steam that isn't being added to their transparent public address).
