Originally released by the Gebr. Klingspor Foundry, the design continued to be made available by the Stempel Foundry (which bought Klingspor in 1956, having already owned some shares) and briefly for phototypesetting systems. Linotype continues to sell Kabel in digital format. Owing to Kabel's popularity, many adaptations and simple knock-offs were sold by other companies, such as Phil Martin's Alphabet Innovations. This particularly occurred in the phototypesetting and digital type periods, taking advantage of the lack of international copyright protection for typefaces.