Two New York museums have taken legal steps to protect their ownership of two Picasso paintings at the core of a claim made by a German-Jewish scholar who says they belong to his family, who were persecuted during Nazi rule.

The Museum of Modern Art (MoMA) and the Solomon R. Guggenheim Foundation announced Friday they have asked a U.S. District Court in Manhattan to declare them the rightful owners of the paintings.

A visitor looks at Pablo Picasso's Boy Leading a Horse, currently owned by the Museum of Modern Art in New York City. It's one of two Picasso works at the centre of an ownership claim by Julius H. Schoeps, a German-Jewish scholar who says they belong to his family. A visitor looks at Pablo Picasso's Boy Leading a Horse, currently owned by the Museum of Modern Art in New York City. It's one of two Picasso works at the centre of an ownership claim by Julius H. Schoeps, a German-Jewish scholar who says they belong to his family.
(Franka Bruns/Associated Press)

Julius H. Schoeps, director of the Moses Mendelssohn Centre for European-Jewish Studies at the University of Potsdam, formally demanded on Nov. 1 the museums hand over Boy Leading a Horse, which is at the MoMA, and Le Moulin de la Galette, held in the Guggenheim collection.

"Evidence from our extensive research makes clear the museums' ownership of these works and also makes clear that Mr. Schoeps has no basis for his claim," the two museums said in a joint statement released Friday.

Both paintings were originally owned by Paul von Mendelssohn-Bartholdy, a German banker who died in 1935, two years after Adolf Hitler came to power. Mendelssohn-Bartholdy was Schoeps' great-uncle.

According to Schoeps, his great-uncle sold his valuable art collection, which included five Picassos, to Jewish art dealer Justin Thannhauser in 1934 or 1935 in order to protect the collection from Nazi hands.

Thannhauser soon fled Germany, eventually selling Boy Leading a Horse to then-MoMA chair William Paley in 1936 and then giving Le Moulin de la Galette to the Guggenheim museum in 1963.

Schoeps says Mendelssohn-Bartholdy had only consigned his precious artworks to Thannhauser.

Schoeps has not had much luck in retrieving what he believes to be his family's art collection.

His 2006 federal lawsuit preventing the auction of Picasso's Portrait de Angel Fernandez de Soto (also known as The Absinthe Drinker ) was thrown out.

In November, a judge in New York state dismissed Schoeps' claim that he be declared the rightful heir to the Mendelssohn-Bartholdy estate.

With files from the Associated Press