Delta Airlines wants you to “keep climbing,” but it might be better to spare your art the bumpy ride—at least according to one lawsuit.

Insurer Zurich American is suing the airline to the tune of $2.6 million on behalf of Christie’s for damage to a painting by Gerhard Richter, one of the most expensive living artists in the world.

According to documents filed in federal court this past February, Delta was entrusted with a Richter Abstraktes Bild (1994) in “good condition” for shipment from New York to Christie’s in Los Angeles. Thereafter the painting was delivered by air and arrived at Christie’s “not in the same like good order and condition as when received by Delta,” according to the brief complaint. “To the contrary, the consignment was delivered in a damaged condition and seriously impaired in value.”

The lawsuit was first reported in the New York Post.

Gerhard Richter. Photo by Sean Gallup/Getty Images.

The plaintiff says that both Christie’s and Zurich American fulfilled their obligations, and that the onus falls on Delta to pay out the estimated $2.6 million in damages.

A Richter Abstraktes Bild, dated 1986, holds the record for the most expensive work by the artist ever sold at auction. The final price (with premium) of $46.4 million was paid at Sotheby’s London in February 2015, according to the artnet Price Database. To date, five Richter abstracts have sold for over $30 million each at auction, the artnet Database shows.

artnet News reached out to attorneys for both Zurich and Delta for comment but had not received a response as of publication time. A spokesperson for Christie’s said the house would defer any comment to parties named in the suit.