Chess Patents

A search at the United States Patent and Trademark Office (see the link below) on 'chess' pulls up close to 3000 patents, with over 300 mentioning chess in the patent title or abstract. Many of these chess patents represent useful extensions of the game that is played throughout the world; the 'Fischer' clock is a good example. Many others are somewhat odd. We've collected a few that we like and that can be understood from a drawing incorporated in the patent.