"Amdahl owed some of its success to antitrust settlements between IBM and the U.S. Department of Justice, which assured that Amdahl's customers could license IBM's mainframe software under reasonable terms."
"By purchasing an Amdahl 470 and plug-compatible peripheral devices from third-party manufacturers, customers could now run S/360 and S/370 applications without buying actual IBM hardware. Amdahl's software team developed VM/PE, software designed to optimize the performance of IBM's MVS operating system when running under IBM's VM operating system."