How many blocks of four of the 1918 Inverted Jenny stamp still exist? How many are in Private hands?

Question

How many blocks of four of the 1918 Inverted Jenny stamp still exist? How many are in Private hands?

Answer 1

93 still exist, one turning up on an absentee ballot in florida in 2006

Answer 2

The 1918 misprints, known as the “Inverted Jenny” after the upturned Curtiss JN-4H biplane, were part of a batch of two million 24-cent stamps issued for the first US air-mail flight from Washington to Philadelphia in 1918.

On May 14th, W. T. Robey sees the postmaster take out a complete sheet of 100 stamps with inverted centers, and, with pounding heart, hurries to purchase the sheet.

Colonel Green separates the sheet in order to sell the stamps for the highest possible price: a block of eight, several blocks of four, and the rest as singles. Colonel Green keeps many of them, and even mounts one in a locket for his wife. On May 18th, 2002, Mrs. Green’s locket is sent to auction, but has no buyer. The philatelic press reports however, that a private sale is subsequently conducted for an undisclosed amount. In October 2005, a block of four «Inverted Jennies» is sold to financier William H. Gross for the sum of $2 970 000. This is the famous block which he then exchanged for one copy of the 1868 Benjamin Franklin Z-Grill.

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