The WKN (“Wertpapierkennnummer”) was the German six-digit alphanumerical code for the identification of a security, which has since been replaced by the internationally used identification ISIN (International Securities Identification Number). It is issued by the Institute for the Issuance and Administration of Securities in Germany (Securities Information).
Although the worldwide standard for securities identification, ISIN, was introduced in Germany in 2003, the WKN is still commonly used and it is included in the ISINs of securities registered in Germany. The twelve-digit ISIN consists of a two-digit country code, a nine-digit national identification code as well as a check digit. The sixth to eleventh digits represent the WKN.