The contents of their art business were sold by Nazis and ultimately ended up in the collection of newspaper mogul William Randolph Hearst, who displayed them in his castle in California.
The handing-over ceremony ended what was a two-year investigation by California state parks officials into the artworks' origins.
State officials said they believed Hearst was unaware of the paintings' origins because they were purchased through a third party gallery. The state acquired the art along with the Hearst Castle in 1972.
One of the paintings will remain at the castle the heirs' request, along with reproductions of the other paintings. Director of Calafornia State Parks, Ruth Coleman said they would be used to tell the story of how Nazis seized such assets.
"More than a million people from all around the world visit Hearst Castle every year," Coleman said. "We are proud to honor the memory of Jakob and Rosa Oppenheimer and share this story that touches countless families affected by the Holocaust."
The oil paintings by Venetian masters were done between 1500 and 1590 and include a woman's portrait by Jacopo Tintoretto (1518-1594), an image of a man believed to be done by Giovanni Cariani (1485-1547) and a Venus and Cupid by Paris Bordone (1500-1571).
Jakob Oppenheimer died in France in 1941 and his wife, Rosa, died in the Auschwitz concentration camp in 1943.