"The Lean", as the move is called, dates back to the late 1800s, at least. Often used by vaudeville comedy teams, the move required amazing leg strength and small body size. Magician Bert Easley popularized a method using special props in the early 1950s, but still the move required strength and balance. Jackson's patent involved a mechanical device that would assist his dancers to be able to perform the move without such incredible strength and effort.

Granted in 1993 to Jackson (and two partners) by the U.S. Patent and Trade Office, patent No. 5,255,452 specifically covers a "system for allowing a shoe wearer to lean forwardly beyond his center of gravity by virtue of wearing a specially designed pair of shoes."

The special shoes were worn not only in the "Smooth Criminal" video, but also during the 1988 "Bad" tour.

The patent rights to the special shoe design ended on Oct. 26, 2005, after Jackson's failure to pay a final maintenance fee to the federal government. That opened the door for anyone to use the design, including magicians! Currently there are a number of gimmicked shoes available on the market. Though few magicians actually use the shoes in performance (even using the shoes, the move still requires a lot of strength), they are quite popular to use for staging publicity photos.