Dictionary
Cantilever Chair (Freischwinger)

The so-called Freischwinger, a chair without rear legs with a seat that cushions the weight of the sitting person, counts among the most revolutionary novelties in 20th century furniture design. The early version of the concept is marked by the 'Kragstuhl', also a chair without rear legs, however, the entire structure was rigid and immobile.
The 'Kragstuhl' was invented in 1926, even though similar cantilever chairs had already been thought up in the late 19th and the early 20th century. The design's breakthrough took some time, even the (unrecorded) steel tube design by Gerhard Stüttgen, stuttgart, from 1923 did not attract any interest.
This is why Mart Stam is regarded the inventor of the first Kragstuhl. The Dutchman thought up a chair made of tubes without rear legs for his wife in 1926, the frame structure was based on one single seamless line. He elaborated this idea for the 1927 Werkbund (Work Federation) exhibition in Stuttgart; and this is how the 'Kragstuhl' was introduced to the public. However, this chair was not a real cantilever chair, as the massive iron parts that stabilized the structure inhibited the seat from cushioning.
It was Ludwig Mies van der Rohe who invented the real cantilever chair that was also presented in the same exhibition in 1927: the seamless line of the frame structure is swung and enables a smooth cushioning of the seat. This first cantilever chair was manufactured by the Berlin metal company Joseph Müller, and as of 1931 by the 'Metallwerkstätte Bamberg', a year later by the furniture producer 'Thonet' (MR 533).
Marcel Breuer advanced the concept of the cantilever chair later; his steel tube works were produced by both Thonet and the company 'Standard Möbel'.
At this time the company 'Standard Möbel' was managed by the clever businessman Anton Lorenz, who had foreseen the chair's success and thus tried to get the rights for its production. After Mies van der Rohe had rejected any kind of co-operation, Lorenz acquired the rights for the cantilever chair from Mart Stam and started his own company 'DESTA' (Deutsche Stahlmöbel - German Steel Furniture). A tedious lawsuit followed that lasted from 1929 to 1932, in the end Mart Stam was adjudged the rights for the cubic 'Kragstuhl'. Thus Anton Lorenz was the sole owner of the production and marketing rights and accordingly a made man.
Mies van der Rohe was also involved in a lawsuit over the rights for the cantilever chair as of 1936. In the end he managed to keep the rights for the technical innovation that he had introduced - the cold bent steel tube, cushioning and various formal properties.
Even though the rights were hard-fought in Germany, imitations of the chair were soon made all over Europe and even in Japan, the imitations dodged the copyright by implementing minor alterations. Additionally, new interpretations of the concept were also thought up, for instance the cantilever chair without front legs, Gerrit Rietveld's "Zig-Zag-Chair" or Hugo Häring's organically swung version.
Both the cantilever chair and the 'Kragstuhl' have been around for some 80 years, and thus do not only count among the greatest achievements in furniture design, but also among the most unusual cases in legal history.

Cf.: Kragstuhlsammlung, Jean-Prouvé-Archiv, Urmodelle der Moderne, cat. mus. Stuhlmuseum Burg Beverungen, 2nd revised and increased edition, Cologne 1998.