The heirs of Victor von Klemperer want their grandfather’s Oskar Kokoschka painting, “Portrait of the Physician Ludwig Adleer,” back from a Belgium museum, according to Bloomberg:

Claims in Belgium have been fewer, said Jacques Lust, an expert in restitution at the Belgian Federal Science Policy Office in Brussels. The country did not have as rich an art- collecting and art-trading tradition as the Netherlands and France by the time World War II broke out and less was stolen, Lust said.

Only 300 looted artworks discovered by the Allies were returned to the Belgian government after the war, compared with more than 5,000 to the Netherlands, Lust said. About 90 percent of the looted works were from private collections, he said.

The country’s main museums have carried out an investigation of works acquired during and shortly after the war and plan to publish this year lists of art that may have been looted. The Kokoschka painting was not included in the investigation because the Ghent museum acquired it in the 1980s, Lust said.

Robert Hoozee, the director of the Museum of Fine Arts in Ghent, said he first learned of the claim for the Kokoschka portrait on Jan. 12. The work was bought from Marlborough Fine Art in London in 1988, Hoozee said by e-mail. He declined to give further details, and said the legal department of the city of Ghent will study the claim.

Dresdner Banker’s Heirs Claim Kokoschka Work in a Belgian Museum (Bloomberg)