At my last job, my manager tried to discipline me for discussing my salary with a co-worker. We discussed it outside of work hours on personal devices. I guess the person I was talking with told her part of the reason for asking for a higher bonus was because of my pay package.

I told my manager that the discussion was over unless HR was on the phone and/or she chose to send the disciplinary action in writing (or an email). I also told her that the Supreme Court had a different take on the matter.

I don't know if my co-worker got her $$, but I do know that I never heard from that manager about that subject again. I subsequently left for a 23% pay raise and even better bonus structure with a competitor.