Sony is coming under some heavy fire after an account was stolen and used to rack up substantial charges, only to offer to reimburse a small portion of those funds. User Kadjar on Reddit noticed that his account was compromised when multiple purchase confirmations began popping up in his email. Acting quickly to remove on-file credit cards and change passwords, Kadjar contacted Sony support only to be told that his refund would be capped. Out of the $600 in fraudulent charges, they only offered $150 and as PSN currency.
If you read the transcript, ‘Malcom’ seems to indicate that the full amount could be refunded upon completion of the investigation. I called to confirm this, and the supervisor I spoke to informed me that there was a maximum of $150 even after investigation.
Further, the customer service rep Malcolm warns Kadjar that going through the bank to reverse the charges will result in his account being banned irrevocably, with no way to recover any licenses lost. Sony also refused to reactivate his Playstation onto the account until six months, which had been deactivated by the account thief and replaced with another system.
Sony does not currently offer two-factor authentication for its Playstation Network.
(Source: Reddit)
MMO Fallout 
I am not sure Sony knows how credit card liability law works in the US.
That said, probably Kadjar should have just gone directly to his card issuer and dealt with them. The law is pretty clear on fraudulent CC usage, if you go straight to the issuer and report the fraud, your liability for fraudulent usage is zero. Sony risks fines and a lawsuit if they decide the laws do not apply to them, not to mention the wrath of the credit card companies if they do not play along as they are supposed to.