The children of the New York art dealer, Ileana Sonnabend, have donated Robert Rauschenberg’s mixed media assemblage, Canyon (1959), to the Museum of Modern Art in New York. While the acquisition is a welcomed addition to MoMA’s existing Rauschenberg collection, the work wasn’t always so warmly regarded.

The Sonnabend heirs received Canyon after their mother’s death in 2007 and the work was soon at the center of a battle between MoMA and the Metropolitan Museum of Art, where the piece had been displayed intermittently since 2005. MoMA ramped up its efforts and promised to add Ms. Sonnabend’s name to the Founders Wall in the museum’s lobby. Officials also vowed to mount an entire show devoted to Canyon as well as Sonnabend, an important player in the modern art movement. While the Met made offers of their own, the Sonnabend family ultimately decided that MoMA was the right home for the work considering the expansive Rauschenberg collection already in the institution’s possession.

Sadly, this is not the first dramatic episode Canyon has been involved in. When the Sonnabend children inherited the work five years ago, appraisers valued the assemblage at $0. The presence of a stuffed bald eagle, a bird that is protected by federal laws, halted any possible sales of trades involving the work. The I.R.S., on the other hand, shrugged this off and claimed that Canyon was worth $65 million and demanded that Sonnabend’s family pay $29.2 million in taxes and another $11.7 million in penalties.

Eventually, a settlement was worked out and I.R.S. dropped all tax charges. In order for this to happen, the Sonnabends were required to donate Canyon to a museum where it could be put on public display. Canyon will be on view at MoMA beginning today, November 28.