Information about cash transactions over the value of $10,000 USD. Any wire transfer over $3,000 USD requires further proof of information regarding the nature of the wire transfer.
Banks also have the duty to inform the IRS of any other suspicious activity and is required by international law to verify with the IRS in the country the money originated from if you declared the money and why it is being sent. You will also be required to pay an international tax gain on any funds over $3,000.00 USD. Depending on your tax bracket. For example, they will report if a customer seems to be trying to split up payments to avoid hitting the $10,000 USD mark by making multiple smaller linked payments. The wire cannot be split, it has to be sent in full to the receiving bank and the tax gain must be covered by the person on the account or the company who is receiving. This is intended to deter and discover any individual trying to avoid paying tax, or any flows of money linked to illegal activity, such as crime, money laundering, or funding terrorism.