Art hoaxes are deceptive practices in the art world where fake artworks or forgeries are presented as genuine. These can involve creating false provenance, altering existing works, or even fabricating entire artists. Notable examples include the Gurlitt Collection, which contained numerous forgeries, and the infamous Dada movement's playful approach to art. Such hoaxes can have significant implications, affecting collectors, museums, and the art market. They challenge the authenticity and value of artworks, leading to legal disputes and loss of trust. The Isabella Stewart Gardner Museum heist is another example, where stolen pieces remain missing, raising questions about authenticity and ownership.