[8] The Post Office finally decided to inaugurate regular service on May 15, 1918, flying between Washington, D.C., Philadelphia, and New York City.

The Post Office decided to issue a new stamp just for this rate, patriotically printed in red and blue, and depicting a Curtiss Jenny JN-4HM, the biplane especially modified for shuttling the mail.

The stamp's designer, Clair Aubrey Huston, apparently troubled to procure a photograph of that modified model (produced by removing the second pilot seat from the JN-4HT to create space for mailbags, and by increasing the fuel capacity).

Aware of the potential for inverts, a number of collectors went to their local post offices to buy the new stamps and keep an eye out for errors.

Collector William T. Robey was one of those; he had written to a friend on May 10 mentioning: “It might interest you to know that there are two parts to the design, one an insert into the other, like the Pan-American issues.

[16] Additional details of the day's events are not entirely certain—Robey gave three different accounts later—but he began to contact both stamp dealers and journalists, to tell them of his find.

This was a block of four (positions 65, 66, 75, 76) with a vertical red guide-line through its center, owned by the collector Ethel McCoy, which was stolen from a stamp show at a Norfolk hotel where it was being exhibited.

The top right stamp from this block has never been found; the two left stamps surfaced in the 1970s as single copies offered in auction catalogues and were recovered by the FBI, although they had been camouflaged by minor mutilation: the portions of the right-edge perforations on which parts of the guide line were originally visible had been trimmed off or abraded to remove the red ink.

The American Philatelic Research Library said it will work to take possession of the stamp once an FBI investigation is complete and other legal matters settled.

[20] In 2019, the 31-year-old musician son of "Bond King" Bill Gross auctioned off a set of five highly valued stamps, including an Inverted Jenny, for a total of $1.9 million, against his father's wishes.

His father reportedly claims that he himself gave each of his three kids some priceless "Jennys" seven years earlier, on the condition that his grandchildren ultimately inherit them.

[27][28] A more recent sale was in March 2020, when a Jenny (position 95) was sold to collector Trevor Fried in Fort Lauderdale, Florida.

[29] On November 15, 2023 an inverted Jenny stamp was sold to a collector, Charles Hack, at a New York Auction for two-million dollars, the highest bid ever made on this rarity.

[34] In November 2006, election workers in Broward County, Florida, claimed to have found an Inverted Jenny affixed to an absentee ballot envelope.

[35] Peter Mastrangelo, executive director of the American Philatelic Society, observed that the stamp was at variance with known copies, due in part to its perforations, although the colors had been reproduced accurately.

[37] On September 22, 2013, the United States Postal Service issued a souvenir sheet illustrating six examples of the inverted stamp denominated $2 instead of the original 24 cents.

Individuals purchasing one of the 100 non-inverted Jenny sheets find a congratulatory note inside the wrapping asking them to call a phone number to receive a certificate of acknowledgement signed by Postmaster General Patrick Donahoe.

[40] A non-inverted sheet purchased by Gail and David Robinson of Richmond, Virginia, was sold in June 2014 by Siegel Auctions "Rarities of the World" for $51,750, with the 15% buyer's premium.

[41] In 2015 the Postal Service's Inspector General called the issuing of a few right side up Jenny airmail sheets improper because regulations do not allow the deliberate creation and distribution of stamp errors.

It was also found that the Service's stamp fulfillment center in Missouri had accidentally failed to distribute 23 of the 30 sheets it was supposed to randomly mix in with orders (the other 70 went to local post offices).

[43] On September 6, 2018, The New York Times reported that the Philatelic Foundation had authenticated an inverted Jenny stamp that had not been seen since the original sheet of 100 was divided in 1918.