I've filled it previously, sent them my id and bill and registration card. Then entered the bank data with swiftcode etc.
Now the ask for this:
We received your withdrawal request. As your withdrawal request met some of our volume and frequency thresholds, we will have to kindly ask you to help us better understand the nature of your relationship with Bitstamp. In order to do so, we require that an additional KYC (know your customer) procedure is completed before we can proceed with the processing of your transfer.
We kindly ask you to send us a high resolution image double page of your international passport and answer the following KYC questionnaire:
1. How did you learn about Bitcoin?
2. The purpose of trading on Bitstamp?
3. What is the origin of the deposited Bitcoins? If mining, please specify your hardware specifications and submit a receipt or an invoice for your mining equipment.
4. What are your future plans and activities planned on our exchange?
5. Do you plan more withdrawals in the future?
6. Which bank are you using? Please provide the complete address and SWIFT code.
We kindly ask you to submit your answers and documents in a reply to this ticket.