Why legal action? It was the standard. I can remember the miracle when users on a PDP-10 could say
buttIGN DSK 5 buttIGN DSK 6
and never have to wait for card turnaound time again.
You all keep missing the most important point. With PDP-10s running TOPS-10, thousands of college kiddies had "stand-alone" system to play with 7x24 (minus the CM and PM scheds which were always posted so the kids could plan). Consider how Lynn started playing with computing. He had a weekend with the machine to himself. Now think about a system that could present almost the whole system to anybody who logged in and any time. That was the power of timesharing. And no user had to wait for an operator to be on duty to get access to the machine. It was on a couple of months before one kid bought his own ASR33 and put in his dorm room. That caused all kinds of tsunami reactions. I never heard what kinds of problems the local telephone exchange had with all that noise on the line.
DEC DOS was: PDP1 3624
CR: Late 70s was when I learned about it from DEC's for X3J3 rep.: Leslie. I...
And not only was the access clock around, the tools available for playing were buttemblers and compilers. The most important of these is that the kid could play with the hardware level instructions and have intimate communications with the OS via UUOs.
DEC DOS was: PDP1
No, it was not the standard. IBM "WAS" the STANDARD. Don't forget that IBM was the MS of its day. Still is. ;^) Why legal action? It was DEC's lawyers' perception that...
Given that availability for thousands, the few who did need to take the system literally stand alone were soon found... and usually hired.