Mt. Gox can ask you to verify your account for absolutely no reason at any time; this is stated in the terms & conditions which you should have read prior to trading on their exchange. On March 13h, 2013, Mt.Gox revised their BTC withdrawal limits: As mentioned above, you can normally withdraw up to $1,000 USD per day without verification, but can only withdraw 100BTC per day (so be careful if the value falls below $100.00 USD per BTC), and accessing Mt.Gox through Tor will get your account flagged for verification. Libertas