If a $65-million Painting Cannot be Sold . . .

. . . what is the painting's taxable value in an art dealer's estate?

In the case of Robert Rauschenberg's "Canyon,"zero.

However, the newly announced settlement with the IRS requires the art dealer's heirs to "donate 'Canyon' to a museum where it would be publicly exhibited and claim no tax deduction."

The lucky museum? The Museum of Modern Art, which agreed to add the name of dealer, Ileana Sonnabend, to the list of the museum's founders. 

Her heirs had been threatened with an IRS claim of $29.2 million in estate tax plus $11.7 million in penalties.