“The customs value is the basis for levying the import duty. In other words, it is the value charged when goods are released for free circulation in the European Union. The customs value is preferably determined on the basis of ‘what the fool will give for it’. However, there are some ifs and buts. For example, when the parties are connected, the mutually agreed price may not be influenced. Connectivity occurs, for example, when two entities that are part of the same multinational company sell goods to each other. A business price must then be agreed in order to prevent import duties from being charged on an amount that is too low.
Source eur.nl