Editing IBM PL/S (section)

== Fujitsu Adaptation ==

A fully compliant PL/S compiler was developed by Fujitsu Ltd in the late-1970s, adapting IBM's PL/I Optimizer compiler source code as its starting point. This PL/S compiler was used internally by Fujitsu, and also by Fujitsu's external affiliates. Whether or not IBM was aware of this unlicensed use of its intellectual property is not known. The phase names of this PL/S compiler were the same as the corresponding phase names of IBM's PL/I Optimizer compiler, with the initial "I" (IBM) in each phase name being replaced by an initial "J" (Japan). All IBM copyright notices (source and object) within the modules were deleted to hide their true origin and ownership.{{citation needed|date=December 2021}}