[pmorici]

If he had bought that many on the open market it would have driven the price up by a large amount. Just go look at the current order book on Bitstamp.net one of the major exchanges. There are only about 5k coins on offer and many of those are for prices well above market.

https://www.bitstamp.net/market/order_book/

[hueving]

That's a terrible indicator. Unless the guy was a complete moron, he wouldn't just submit an order to the market to buy 30k coins at the market price. It would be trickled over the process of a couple of weeks.

By your same logic, the coins he bought are hardly worth anything because if he tried to sell them it would just crash the price. There is only about 5k worth of buy orders in the book at the moment.

In fact, if he paid above market price, it would be in his interest to make sure the number got 'leaked' to encourage rampant speculation to drive up the price beyond what he paid.

[pmorici]

Yeah, that's the point. You would have to go through a lot of work slowly buying coins over several weeks to get to 30k and even then it would affect the price. So it makes sense to bid a little high and get them all in one go.

[hueving]

What 'work'? It would be trivial to just keep setting small orders until you reach your target. With how volatile bitcoin is there is no reason to chase the price up.

[haakon]

They don't seem to show their whole order book on that page. If you look at the cumulative depth chart at http://bitcoinity.org/markets/bitstamp/USD, it currently shows over 12K BTC asks. Buying all that in one fell swoop would drive the price to over $4000 though.