Neutrals Identified When?

I know I saw this not too long ago on the BB - but when did the NEC first required neutrals (white wires) attached to breakers to be identified or marked as hots?

1968 - Thanks Stephen

Code inspections?

As Joe inferred, who cares when code required something. Report it for the safety issue it is.

Is this correct? It’s been required for every code cycle since 1968?

Relax guys - I’m not doing code inspections - just curious LOL!
I got that year from a previous post - see the link in Stephen’s post above.