February 10, 2014, marked the 123rd anniversay of the issuance of U.S. Patent No. 446,054 on the Ouija Board.  As the story is told by descendants of the inventors, the Patent Examiner refused to issue a patent without proof tha the invention worked.

The requested demonstration was made during an Examiner Interview, as dramatically recounted in the Smithsonian in October 2013:

the chief patent officer demanded a demonstration—if the board could accurately  spell out his name, which was supposed to be unknown to Bond and Peters, he’d  allow the patent application to proceed. They all sat down, communed with the  spirits, and the planchette faithfully spelled out the patent officer’s name.  Whether or not it was mystical spirits or the fact that Bond, as a patent  attorney, may have just known the man’s name, well, that’s unclear, Murch says.  But on February 10, 1891, a white-faced and visibly shaken patent officer  awarded Bond a npatent for his new “toy or game.”

Read more:  http://www.smithsonianmag.com/history/the-strange-and-mysterious-history-of-the-ouija-board-5860627/#ixzz2t35YW21m.  What actually happened during the interview is a mystery — a problems with many Examiner Interviews today, despite the provisions of 37 CFR 1.133 and MPEP 716.  We do know that the patent did issue, and that the patent owners used the issuance as an endorsement of the operability of their invention for many years.