Fox Talbot had developed the calotype process and patented it in 1841 to run until 1855. By 1852, many in the photographic community felt that Fox Talbot's insistence on the economic rights in his intellectual property were hampering the development of photography in England and had called upon him to relinquish his patent. He had made a concession by allowing a free licence to amateur photographers but he still insisted that professionals pay an annual licence fee. The situation was exacerbated by Fox Talbot's insistence that Frederick Scott Archer's collodion process was covered by his patent. The collodion process was widely used and there was disquiet among the professional photographic community at the payment of a licence to Fox Talbot, rather than Archer, for its use.