What is the "participation reservation fee"?

Following admission to the LLM programme, the Law School will ask you to make a "participation reservation" payment (around 300 EUR) before a given deadline. Receipt of the payment guarantees your place in the next LLM session. If the payment is not received by the deadline, the LLM programmes reserve the right to withdraw you from the list of the selected candidates, and give your place to a candidate on the waiting list. 
The payment is non-refundable in case of non-participation in the next LLM session.