The art of shedding light on gifts with possible Nazi ties

When Georges F. Keller began donating paintings by masters like Henri Matisse and Salvador Dali to the Kunstmuseum in Bern his reputation was not in doubt. The Swiss-Brazilian national had been a respected art dealer who gifted 116 works to the museum from the 1950s until his death in 1981. But last year, the Kunstmuseum’s provenance researcher came across an archival document linking Keller to Etienne Bignou, a Frenchman now considered a “red-flag” dealer because he traded art with Germans in Nazi-occupied Paris. For the Bern museum, the potential fallout of gifts with possible Nazi ties was not new. The museum was the sole heir of hundreds of major pieces left behind by Cornelius Gurlitt, who died in 2014 and whose father, Hildebrand, was tasked by the Nazis with selling art stolen from Jews or confiscated as “degenerate” works. The case captured huge global attentio