EVE 3 trillion ISK exploit

Via Brokentoys I read that CCP confirmed having banned 70 accounts over several allied corporations, who had been exploiting the game for 4 years unnoticed, producing nearly 3 trillion ISK in the process. One of the exploiters thanks CCP for making it possible to buy game time cards with ISK, he had been paying his account for the last 4 years with duped ISK. A 60-day game time card apparently goes for around 600 million ISK, so the complete amount of duped money could have paid for 5,000 months of EVE and thus been worth $75,000. But probably CCP can't do anything beyond banning those accounts, as duping virtual currency isn't illegal, even if you can "pay" something with it that normally costs real money. Otherwise that would have been one quite interesting lawsuit.