Concardis offers card payment terminals as well as payment technology for e-commerce groups and is viewed as a non-core business by its key owners.

With a 16 percent stake, Deutsche Bank (>> Deutsche Bank AG) is the group's largest shareholder, while smaller stakes are held by Commerzbank (>> Commerzbank AG), Unicredit (>> UniCredit SpA) as well as savings and cooperative banks.

Concardis is hoping a new owner will invest in new technologies and an expansion of its business, which is so far heavily reliant on Germany.

Last year, Concardis posted core earnings of 33.9 million euros on sales of 480 million euros last year.

Concardis and Advent declined to comment.

Bain Capital was not immediately available to comment.

(Reporting by Alexander Heubner; Writing by Harro ten Wolde; Editing by Christoph Steitz)

Stocks treated in this article : Deutsche Bank AG, UniCredit SpA, Commerzbank AG