Commerzbank AG (CRZBY) stock surged to the top of Germany's Dax in the first hour of trading Tuesday on reports that it had hired advisers as takeover interest builds.

Commerzbank shares were marked 2.98% higher at 9:45 am in Frankfurt, changing hands at €11.76, extending a more than 11% gain over the past three months.

The German bank has reportedly hired Goldman Sachs and Rothschild to advise on a possible takeover, the Financial Times reported Tuesday, as European rivals including French lender BNP Paribas (BNPQY) circle.

BNP Paribas shares were down 0.12% in Paris, changing hands at €67.79.

Commerzbank, which is Germany's second largest listed lender, is said to be preparing for all its options, not just a defence strategy.

Commerzbank has a market cap of €14.66 billion, which could mean that any potential deal would be the biggest in Germany's banking sector in more than a decade.

Italy's UniCredit and France's Credit Agricole (CRARY) have also been floated as possible bidders for the lender.

The bank could also fall into private hands after private equity group Cerberus built a 5% stake in Commerzbank, according to Factset data.

A deal could be complicated as the German government owns a 15.6% stake in the lender.

Commerzbank booked an €807 million restructuring charge in the three months through June for job cuts spurred by its digital overhaul. The charge, which drove a larger-than-expected quarterly loss, is less than the €1.1 billion Commerzbank initially expected to spread over two years, largely because of previous layoffs, staff turnover and savings through transfers and replacements, the lender said in June.

The company announced it would fire some 9,600 employees in September 2016 when executives introduced the Commerzbank 4.0 plan, a four-year initiative to buoy profits by focusing on two core segments, corporate and consumer clients, and automating much of its operations.

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