my cousin sold his bitcoin to a guy in Thailand and that person made direct payment to my cousins bank account in Singapore from his Thailand bank but now the bank in Singapore is asking my cousin to produce his income source and has freeze that transaction money in his account. my concern is does the bank have that authority to stop my cousin from taking money out from his account and give such reason or excuses ?
is there any legal solution ? is it possible to sue the bank ?
Under the Anti Money Laundering guideline, every country has set up a tolerance level based on transaction value. For example, in India every bank has a tolerance level of 1 million Indian Rupee. Anything above that amount automatically gets reported to the Government's AML committee. If the transaction value is not near to the usual volumes, bank can definitely ask for the source of the money and freeze the amount until they get a satisfactory answer.
I am sure, the amount of transaction is well above the tolerance level set up by the banks of Singapore and that's why they freezed the amount. Legal ways won't do much good. Rather try to prove the bank that the sold bitcoins were not obtained through illegal means. I believe bitcoin is legal in Singapore so if your cousin can prove that bitcoins are obtained through legal activities, you can expect some positive outcome!