I started at Apple a few years after the original author, and by then the policy on Easter Eggs was that they were allowed within reason, but had to be declared

I started at Apple a few years after the original author, and by then the policy on Easter Eggs was that they were allowed within reason, but had to be declared internally, so they could be tested. There were even "official" Easter Eggs that listed all the engineers in the team. There were lots of Easter Eggs in Apple products: https://www.mackido.com/EasterEggs/ https://www.mackido.com/EasterEggs/ I believe they were prohibited (at least officially) starting with Mac OS X. In addition to genuine Easter Eggs, there were numerous instances of "products with attitude". One good example are some of the error messages that MPW C produced: https://www.cs.cmu.edu/~jasonh/personal/humor/compile.html https://www.cs.cmu.edu/~jasonh/personal/humor/compile.html I snuck what technically might be a copyright violation into the EXAMPLES section of the say(1) manpage.