>Yes, it's company policy, but this is more like running into a meeting and then interrupting it so you can start reciting NLRB policy than it is posting a flyer.

True, but it seems kind of shady to come down harder on an employee based on the content of the interruption, and that content notifying of the right to organize.

Like, imagine there's a documentation page for http cookies. Consider two scenarios:

A) Rogue employee adds to the bottom of the page: "Cookies are also delicious treats given as a reward on the internet."

B) Rogue employee adds to the bottom of the page: "Employees reading this are reminded of their right to organize under NLRA."

Let's say that in scenario A, an employee would typically get a written warning, and in B, you always got fired. In that case, I think it would be fair for B to say -- at least in common speech -- "I got fired for notifying employees of their right to organize."

This is true, even though there is a general policy of not adding non-topical messages to doc pages, because the punishment never escalates to firing unless it's something like scenario B. (In a legal context rather than common speech I don't know enough to say whether it would be legal.)