If you win a prize amount higher than $600 in a Challenge, you’ll be sent applicable tax forms that you’ll be required to fill out in order to receive the prize. Winners located outside of the US are still required to complete paperwork—the forms you'll need to complete are just a bit different.
The purpose of sending you these forms is so that we can collect your taxpayer info for our records. Then, at the end of the tax year, we're required to send you a summary of your earnings, in case you need it when you file your taxes for this year. That does not necessarily mean you'll be required to pay taxes on your prize money—that depends on a lot of other factors, like where you live, and your total income.