After AT&T dropped the Multics project in March of 1969 Ken Thompson and Dennis Ritchie of Bell Labs through a combination of discarded equipment and subterfuge continued to work on the project eventually writing the first programming manual for System I in November 1971. A paper published in 1974 in the Communications of the ACM on Unix brought a flurry of requests for copies. Since AT&T was restricted from selling products not directly related to telephones or telecommunications they released it to anyone who asked for a nominal license fee. At conferences they displayed the policy on a slide saying "No advertising, no support, no bug fixes, payment in advance." From that grew an ecosystem of users supporting users much like the Linux community. The rest is history."
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