The Otsuka is the only place in the world to see all six panels of El Greco's 41-foot-tall "High Altar" together.

FORBES: Michelangelos: Made in Japan

The Otsuka is the only place in the world to see all six panels of El Greco's 12-meter- tall "High Altar" together.

FORBES: Michelangelos: Made in Japan

The family, who are also suing state-owned museums, say Hungary has about 40 works, including paintings by El Greco.

BBC: Family of art collector sues Hungary over Nazi loot