An inverted airmail stamp, a philatelic term, refers to a postage stamp printed with the image of an airplane oriented upside down relative to its intended design. One famous example is the... Read more »
An inverted revenue stamp, affixed to correspondence or official documents, typically signifies a protest or act of rebellion. For example, during periods of political unrest, citizens might deliberately invert required stamps to... Read more »
An inverted postage stamp typically signifies a deliberate signal, often interpreted as a request for assistance or a sign of distress. While not officially recognized by postal services, this practice has a... Read more »