$410-$430 ??
You are delusional, the price will drop to 300 after it hits 400 watch.
From where are you getting this numbers, i highly believe that the chinese exchanges will pump the price to more than 400 not dropping it below 400 again.
Bitcoin is heavily affected by market manipulation, but what I wonder is...where do these people sell such huge amounts of Bitcoin?
on the market? slowly, without increasing too much the pressure to not scare those that will buy their dump
privately do avoid completely affecting the market, and have more freedom on the quantity?
There are people who get these bigger amounts of Bitcoin for certain people. Of course, they get paid for doing this.
The advantage is that they can buy let's say 1000 bitcoins at the current, average price which would never be possible on the exchange. Also they end up buying considerably cheaper these big amounts at the end!