Brussels Stock Exchange
The BEL 20 is the benchmark stock market index of Euronext Brussels. In general, the index consists of a minimum of 10 and a maximum of 20 companies traded at the Brussels Stock Exchange. Since 20 June 2011, the BEL20 has contained 20 listings, with the exception a one month period in May-June 2018 when Ablynx stock was removed following the takeover by Sanofi, only to be replaced mid June by arGEN-X.