The Pan-American inverts were the first bi-colored postage stamps produced by the Bureau of Engraving and Printing and the first invert postage errors issued by the Post Office since the 1869′s.

The 1c Pan-American Inverts were found in at least four different post offices around the country. Approximately 600 to 700 are known, including thirteen blocks of four, a block of six and a block of 20, some of which may have been broken into singles. This is the only example with an imprint or a plate number contained in our records.

Sold by Robert A. Siegel Auctions Galleries on 19 June 2010 for US$145,000.