I agree that buying a large sum on the OTC markets is probably because they don't want the price to go up.

But I don't know if it's such good news even if 'long term'. We must remember these people are sharks and we would be foolish to think that they would buy in for X amount and just sit and wait for the price to go up. I consider it much more likely that they would get a sizeable position in the market, and then follow up by playing the market in order to increase their stacks. You mentioned long term vs short term, and I'm not sure there's a difference.

Short term simply wanting to crash the market makes little sense, unless it is in order to buy it all up cheap which would make them a long term investor rather than short term. I doubt any party would simply throw billions 'just to kill Bitcoin'. After all, profit makes the world go around. But if there's profit to be made by crashing Bitcoin, then buying it all up for cheap, then I definitely think they're going to try it. It wouldn't be costly if it turned out to be the most profitable thing ever. And what's a few billion here and there, for these kind of people?