15. Other non-current assets

Other non-current assets consisted of non-current restricted cash, financial assets held at fair value through profit or loss, and other non-current assets.

Restricted cash on 31 December 2020 was composed of bank guarantees on real estate lease obligations in Belgium and in the Netherlands for €1.0 million. and €0.5 million, respectively.

Financial assets held at fair value through profit or loss consisted of equity instruments of both listed and non-listed companies. We have no restrictions on the sale of these equity instruments and the assets are not pledged under any of our liabilities. These instruments are designated as financial assets held at fair value through profit or loss. The fair value of the equity instrument of the listed company is determined by reference to the closing price of such securities on Euronext at each reporting date (classified as level 1 in the fair value hierarchy). The fair value of the equity instrument in the non-listed company has been determined mainly by reference to the initial transaction price (classified as level 3 in the fair value hierarchy).

Fair value changes on financial assets with fair value through profit or loss are recognized in other financial income/other financial expenses.

The table below illustrates these financial assets held at fair value through profit or loss as at 31 December 2020 and 2019.