This chair (originally nr. 17, later nr. 207, also called "Long John") was designed by Michael Thonet, the founder of Thonet, around 1865. It is said that the design was based on the architecture of Crystal Palace (London), the location of The London Great Exhibition of 1851. This piece has an attribution mark, I am sure that it is completely authentic and take full responsibility for any authenticity issues arising from misattribution