One Equity Partners, the private equity business of Bank One in the US, is attempting to sell HDW, the German submarine manufacturer it bought only last year in a controversial deal.

One Equity bought HDW in two parts last year for €650m ($701m). The controversy arose following accusations from the German federal cartel office that the acquisition should have been examined more closely, suspecting that HDW was just "parked" with Bank One before being sold to a US-based competitor. The German government was also concerned that the shipyard should not fall entirely into foreign control because of defense implications.