First Ask your bank. If they do not know ....
SL govt and US govt signed a receiprocal Tax evasion agreement sometime back . So, there are obligation on each side to comply. The banks needs disclosures of the accounts relating to US funds or US related income for them to find out whether there are any tax evasion of US funds in SL. so this is the information that they will collect for this purpose. Like any other thing eg. Anti money laundering , terrorism or drug or organized crimes related funds, proceeds of crime etc.
Just comply
