Grant & Eisenhofer P.A. and DRRT filed the lawsuit in Copenhagen on behalf of investors from 19 countries, asserting "fraud claims stemming from a massive Russian money-laundering scheme and multi-year cover-up by Denmark's largest bank and its senior leadership."
The bank's share price halved in 2018 as the scandal unravelled and it replaced both its CEO and chairman.
At a shareholder meeting on Monday in Copenhagen, several shareholders voiced concern about potential lawsuits from investor groups.
"It is our fundamental position that the bank has lived up to its information obligation," Danske's new chairman Karsten Dybvad told shareholders. "As such we don't find any basis for lawsuits or for a settlement."
Danske Bank was not immediately able to comment when contacted by Reuters on Tuesday.
The investors are seeking $475 million (358 million pounds) in damages, Grant & Eisenhofer said in a statement dated March 18.
Danske and four former top executives are already facing a lawsuit in New York filed in January by a U.S. pension fund. That accuses the bank of defrauding investors and inflating its share price by hiding and failing to stop widespread money laundering.
Authorities in Denmark, Estonia, France, Great Britain and the United States are investigating the payments, including in a criminal probe by the U.S. Department of Justice. Danske has said it has been cooperating with authorities.
(Reporting by Stine Jacobsen, additional reporting by Jacob Grønholt-Pedersen, editing by Louise Heavens and Kirsten Donovan)