On December 5, 1854, Aaron H. Allen received U.S. Patent No. 12,017 on an Opera Chair:

The seat pivoted to a vertical orientation when not in use, to allow people to more easily traverse a row, while allowing theaters and similar venues to space rows of seats closer together to increase capacity. This style of seating revolutionized theater-type venues, and is still in use today.

Aaron endured a patent interference, and at least one infringement suit.