Laws differ by countries of course, but assuming you are American from post history, no, if it can be proven it was stolen by Nazis it legally belongs to the person who it was stolen from (if still living) or their families, if dead. There was a law recently passed to make it easier for Americans to bring suits to recover their art. This site has a good overview of the work undertaken to return art and the moral and legal principles of looted art restitution.