The stamp, showing the yellow background inverted relative to the image and text, is also known as the Day's Folly after Postmaster General J. Edward Day who ordered the intentional reprinting of the yellow invert commenting, "The Post Office Department is not running a jackpot operation."

The stamp reprint was in effect a deliberate error produced by the Post Office Department to avoid creating a rarity.

The finder of the discovery sheet, a New Jersey jeweler named Leonard Sherman, obtained a court injunction against the reprinting, but it came too late to stop production.

[4] In 1987 Sherman donated his sheet to the American Philatelic Society because the reprint dashed his hopes of owning a valuable stamp error.

[5] Mad magazine later commemorated the affair by printing a parody stamp that looked similar to the real issue, but put a crying Sherman in place of Hammarskjold with money flying away from him.