The B.K.F. Chair—also known as the Hardoy Chair, Butterfly Chair, Safari Chair, Sling Chair, or Wing Chair—was designed in Buenos Aires. Its name credits its three designers. The first two B.F.K. chairs to come to the United States went to Fallingwater, Edgar Kaufmann Jr.'s home in Pennsylvania (designed by family friend Frank Lloyd Wright), and to MoMA. Kaufmann accurately predicted that the lightweight and inexpensive lounge chair would become hugely popular in the U.S., particularly on the West Coast. Artek-Pascoe produced the chair from 1941 to 1948, sending royalties back to Argentina. Knoll Associates acquired U.S. production rights in the late 1940s and unsuccessfully pursued legal action against unauthorized copies, which continue to be produced to this day.
from What Was Good Design? MoMA's Message 1944–56, May 6, 2009–January 10, 2011