A Washington, D.C., federal judge ruled late Thursday that the descendants of Baron Mor Lipot Herzog, a wealthy Jewish Hungarian art collector, can sue the Hungarian government for the return of art seized by Hungarian officials and the Nazis during World War II.

In denying (PDF) the bulk of Hungary’s motion to dismiss, U.S. District Judge Ellen Segal Huvelle found that Herzog’s heirs offered “substantial and non-frivolous” claims that Hungarian officials at the time violated international law in taking the paintings, meaning the Hungarian government is not immune against litigation under the Foreign Sovereign Immunities Act.