Allianz, the German insurer, has become the final legacy shareholder to sell its stake in Deutsche Börse, bringing the Frankfurt stock exchange operator's freefloat up to 100%.

Allianz was the only remaining shareholder with a stake of more than 5%. Deutsche Bank sold its 9.31% stake in the stock exchange operator in October last year at €34.5 a share, raising €359m. The sale increased Deutsche Börse's free float enough to nudge the stock into its own blue-chip Dax index.