The stake in the firm amounts to around 18%. Both parties have agreed not to disclose the value of the transaction.

"The minority stake in Nixdorf Kapital AG is a further step towards expanding our range of sustainable asset management services. The partnership with Nixdorf Kapital AG will broaden our product range by adding a promising dimension of impact investment," said Commerzbank's Thomas Schaufler.

(Reporting by Paolo Laudani; Editing by Miranda Murray)