A Printing Flub Created the Most Famous U.S. Stamp. You Can Buy One This Fall for $2 Million.

Hailed by Siegel as “an icon in the world of stamp collecting,” the introduction of the 24 cent Inverted Jenny coincided with the inaugural May 15, 1918, airmail flight that would enable Americans to communicate faster. 

Decked out in patriotic colors, the stamp depicts a blue Curtiss JN-4H (“Jenny”) within a red and white border that is—whoops!— flying upside down. 

“It’s the most famous error in stamp collecting,” says Scott Trepel, president of Siegel Auction Galleries headquartered in New York. “In their rush to get the stamps finished on time for the first airmail flight, they created an invert during the printing process.”

More: Japan to Kenya: the Biggest Hotel Launches This Fall

The Post Office let one sheet of 100 get into public hands, according to Trepel. The other error sheets were destroyed. 

Stamp collector and part-time dealer William Robey bought the error sheet for US$24 on May 14, 1918, at his local Washington, D.C. Post Office. He knew exactly what he’d found, according to Siegel. He subsequently sold the sheet for US$15,000.

The Inverted Jenny being sold this fall is the best example of the 100 stamps from the sheet, according to Trepel, who has auctioned over two-thirds of the original 100 during his career.

The roughly one-inch square stamp up for bidding on Nov. 8 was previously sold by Siegel Auction Galleries on Nov. 15, 2018, for nearly US$1.6 million, then a world record for an Inverted Jenny as well as a 20th-century stamp, per the auction house. 

At the time it was rated by experts at 90 on a scale of 10 to 100, based on centering and condition. It has since been upgraded to 95 by The Philatelic Foundation and Professional Stamp Experts.

“It simply doesn’t get better than this for a collector,” says Siegel, adding that the current unidentified owner said he’d “gotten a lot of pleasure out of it. Now it was time for someone else to do that.”