Alexander S. C. Rower, the artist's 35-year-old grandson and the director of the Calder Foundation, is having trouble finding a building.
He is also involved in the Calder Foundation and works to restore Calder sculptures for exhibitions.
The US copyright representative for the Calder Foundation is the Artists Rights Society.
After having worked mainly on cataloging Calder's works, the Calder Foundation is now focusing on organizing global exhibitions for the artist.
In 1994, the Calder Foundation declined to include the mobile in the catalogue raisonné on the artist.
A woman who answered the telephone at the Calder Foundation yesterday said that she could not reach Mr. Rower.
"It took time to get approval from the landmarks commission and the Calder Foundation."
The grant will enable the museum, in collaboration with the Calder Foundation, to install 10 to 15 sculptures on a rotating basis over 12 years.
The Calder Foundation is not much more enamored of the exterior.
"The Whitney lost a masterwork, without a doubt," said Alexander S. C. Rower, the director of the Calder Foundation and the artist's grandson.