A decades-long dispute between the Thyssen-Bornemisza Collection Foundation in Madrid and the Jewish heirs over a picture by the French impressionist Camille Pissarro stolen by the Nazis in Berlin in 1939 is entering a new round.

The US Supreme Court, the Supreme Court in Washington, upheld a lawsuit filed by the American heirs.

They had asserted an error of law by a district court in California.

A decision has not yet been made on a possible obligation to return the painting "Rue St.-Honore, Apres-Midi, Effet de Pluie" from 1897 with an estimated value of around 28 million euros.

The Thyssen-Bornemisza Foundation said it would not have to return the painting despite the new court decision, Spanish media reported.

In 2020, the Californian court dealt, among other things, with the question of whether the return obligation must be decided under Spanish or US law.

Both US federal law and Californian law contain regulations on this.

The court relied on US federal law and concluded that Spanish law applied.

These provide that, in the case of a bona fide purchase, it is sufficient to have a painting on public display for six years in order to become the legal owner and not have to return it.

This also applies if it was stolen earlier.

The Supreme Court has now made it clear that the choice of law issue should not have been decided under US federal law but under California law.

Sold at a ridiculous price

There is no time limit under American law and ownership of such a painting cannot be acquired, so it would have to be returned.

It was unclear whether a Californian court, taking into account the Californian rules for the choice of law, could come to the conclusion that US law should be applied instead of Spanish law.

The Berlin Jew Lilly Cassirer was forced to sell the painting in 1939 at a ridiculous price in order to obtain an exit visa and thus save herself from Nazi persecution.

After the end of the war, she and her grandson Claude Cassirer, who now lived in the USA, searched in vain for the picture.

It was considered lost.

It was not until 2000 that Claude found out that the painting was in the Thyssen-Bornemisza Museum in Madrid.

The Swiss Baron Hans Heinrich von Thyssen-Bornemisza assembled this collection and sold it to the Spanish state for 350 million dollars in the early 1990s.

He had bought the painting of Pissarro in a New York gallery in 1976.

Lilly Cassirer died in 1962, Claude in 2010. His son David is now continuing the fight for the painting.