Minnesota Mining and Manufacturing Company (3M) was founded in 1902 in Two Harbors, Minnesota, United States of America^[1]. The company produces products under many subsidiary brands including The Filmsort Company which they acquired in 1959^[2].

The Filmsort Company manufactured Aperture Cards and equipment for creating and viewing the microfilm elements of Aperture cards. The company began as Film ‘N File, Inc in 1945/46. The company licensed technologies from John Langan, a United States of America’s Office of Strategic Services (OSS) employee who had developed the Aperture card technology during World War 2. Film ‘N File, Inc. was renamed to Filmsort Inc in 1951 and was acquired by the Dexter Folder Company before acquiring its final name Filmsort Company in 1957^[2].

Filmsort cards commonly carry the MMM abbreviation on the card edge, but it is unclear if 3M manufactured punch cards under any other subsidiary brands that may also use this prefix.