The copyright status of the Multics source code is somewhat complicated. The various source files herein contain copyright notices by various organizations. None include permission to redistribute. However, Honeywell and Bull HN distributed Multics source code, which indicates that they believed they had sufficient permission to do so.

Later Bull HN released the source code to MIT "for any purpose and without fee", again indicating that it believed that it had sufficient permission to do so. See Multics_sources, which is also included here both as a convenience and as a requirement for the redistribution of the Multics source code. After the the Group Bull release, MIT made the source code available on the Internet.

A dedicated group of Multicians then used that code base to reconstruct a version of Multics that operates on the dps8m simulator platform. Subsequently, they have made significant enhancements to Multics (although there have been no changes in fundamental structure). Unfortunately, they have declined to provide a copyright notice allowing redistribution of that code. However, this appears to be due to neglect rather than purposeful, and we have chosen to treat that code as covered by the original Bull HN copyright, mutatis mutandis.

(210726 - dmw)