The return to the index comes after Commerzbank launched a major overhaul two years ago that saw thousands of job cuts and branch closures that restored profitability.

"We have come to stay," Commerzbank CEO Manfred Knof said before ringing the opening bell at the Frankfurt stock exchange. "The return of Commerzbank is a good signal for the German banking market."

In 2018, Commerzbank, still partly owned by the German government after a bailout, was expelled from the DAX index to make room for Wirecard AG, a payments company that collapsed in 2020 after a years-long fraud was exposed.

Following Wirecard's demise, Deutsche Boerse AG, which compiles the DAX index, revamped it to include 40 companies, rather than the previous 30, and made membership criteria tougher.

Since its founding in 1988, the DAX has been Germany's answer to the Dow Jones Industrial Average in New York and the FTSE in London, with its members forming the corporate elite in one of the world's largest economies.

Other members include Siemens AG, Volkswagen AG, and Allianz SE.

Commerzbank will replace Linde Plc, which is giving up its listing in Germany.

(Reporting by Marta Orosz, Writing by Rachel More, Editing by Miranda Murray)