The Netherlands has a mixed system, in which both the industry and a government agency COVA are required to hold emergency stocks.
According to Dutch legislation, any company that brings more than 100 Kt of qualifying products into the Dutch market (in any given calendar year) is obliged to hold 5% of such excess quantities as compulsory stock. In total, this equates roughly to 13.5 days of net imports. COVA is responsible for holding the balance of the total national requirement of 90 days of net imports - i.e. approximately 76.5 days of net imports.
Company stock obligations are held as part of normal operating inventories. Due to their international activities, refining and supplying companies tend to hold unusually high volumes of stocks as part of normal operations.
Due to the high cost of storage in the Rotterdam area, around 9.6 mb (1.3 Mt) of COVA crude oil stocks (or 30% of its total obligation) are held in salt caverns near Wilhelmshaven (Germany). The remaining quantities of crude are held in above ground storage in the Netherlands.
COVA obligation is subject to a restriction that only up to 30% of its stocks can be held abroad. This restriction is not based on formal law, but on a guideline of the executive board of COVA.
COVA can use stock tickets or reserved stocks with a third party. However, COVA has an internal policy on such tickets whereby they can be used only for products stored within the Netherlands. Moreover, stocks tickets may not account for more than 25% of the total compulsory stockholding obligation.