If the number alone doesn't boggle your mind, consider this: The price is nearly double the previous auction record for a work of art.

WSJ: Taking It to the Street | The Shift

Nevertheless, its record-breaking, headline grabbing sales of the late have been a double-edged sword for the auction house.

FORBES: Sotheby's Increases Buyer's Premium On Back Of Lackluster Results

Having to pay for emission allowances up front in an auction, as you suggest, while also having to pay for these new plants would be a double blow for customers.

ECONOMIST: Capping, not taxing