The descendants of a Jewish art collector just scored a major win in their quest to reclaim a valuable Pissarro painting stolen by the Nazis during the Holocaust.

On Monday, the US Supreme Court breathed new life into the Cassirer family’s decades-long battle against Spain’s Thyssen-Bornemisza museum for Camille Pissarro’s 1897 masterpiece “Rue Saint-Honoré, in the afternoon. Effect of rain.”

Painted from his hotel window in Paris when he was in his late 60s, Pissarro captured the bustling street scene below through a veil of rain. Valued at $40 million, the painting shows pedestrians with umbrellas and horse-drawn carriages navigating the wet boulevard, all rendered in the misty, atmospheric style that defined his unique impressionistic style.

In 1900, German Jewish collector Julius Cassirer purchased it directly from Pissarro. When the Nazis rose to power, his daughter-in-law was forced to surrender the masterpiece in exchange for a visa to flee Germany. The Nazis later auctioned off the stolen artwork in 1943.

Lilly spent years searching for the painting after the war, unaware of its fate. It wasn’t until the early 2000s that her grandson, Claude Cassirer, discovered the Pissarro in the collection of the Museo Nacional Thyssen-Bornemisza in Madrid. When the museum refused to return the painting, the Cassirer family initiated legal proceedings.

In September, the US Ninth Circuit Court of Appeals had ruled that the Spanish museum was not obligated to return the artwork to Cassirer’s heirs in California. However, citing a new California law specifically crafted to help Holocaust victims recover looted property, the US Supreme Court overruled the lower court’s decision.

“We hope Spain and its museum will now do the right thing and return the Nazi-looted art they are holding without further delay,” an attorney for the family said in a statement following the Supreme Court’s ruling.