The various wallets considered to belong to Mintpal contain ~9.5% of the coin supply, around 444,000 DRK.

How many Masternodes are laying around there ?? !!....>
How was is determined that those wallets belong to mintpal? Just curious.
...you withdraw from mintpal and the money come from one of this addresses....
eddit: most times, you get your money from more than one address.
mintpal has some balancing-thing on the way.
so you can associate the adresses.
if you have eg. 3 addresses sending to you, each about 33% of your withdrawel and 1 address filling the rest to make the number strait (this is at least how my withdrawals looked like - schematically) ,
you can see which transactions from other addresses are coordinated. (nearly same amount, same time, to same address)
you can create a map starting by the addresses you know, and look which overlap.