The Art Restitution Act, Federal Law Gazette I No. 181/1998, was adopted in 1998. The aim of the law is to return objects in the collections of the Austrian federal museums, National Library, and Bundesmobiliendepot acquired by the state during the Nazi regime to their original owners or legal successors. The investigations required for restitution are carried out systematically by the Commission for Provenance Research. The Art Restitution Act was amended in 2009.
Since the Art Restitution Act came into force, provenance researchers have investigated the collections of the Natural History Museum Vienna. So far, the Art Restitution Advisory Board recommended the restitution of objects stored in the Natural History Museum Vienna in six cases. In three cases the Advisory Board was not in favor of restitution. In two other cases the legal successors of the former owners were offered comparable geological objects.
See also: http://www.provenienzforschung.gv.at/