I am not a lawyer, but I'm not aware of any such law. Public employee salaries are already publicly posted. You can look up the salaries of any public employee - including those at state universities, municipalities, etc
Honestly, I think we'd all be better off if corporations were required to publicly post not just salaries but all financial information. I think we should have an open books law. It would help level the playing field in all manner of negotiations, make it easier to study the economy and find out what's really going on, and would make it much, much harder to get away with corporate malfeasance. It wouldn't give any particular corporation a competitive advantage over any other because they would all have each other's information.
pay secrecy really only helps to make employers more money while punishing the people that aren't as good at negotiating that one week of their life that they did it at that job.
just like tying healthcare to an employer only really benefits the employer and not the people. (people accept jobs that they otherwise wouldn't take because "they need the insurance" etc.)
Employers can disclose them if they choose (but they don’t for obvious reasons) and many (most?) employees prefer to not have the world know what their salary is.
> Serious question: which law protects salary information? And if this law exists, does it apply to employers only or does it extend beyond that?
None. Incidentally your ability to communicate your salary is protected by the first amendment and various labor laws: Your employer cannot prevent you from sharing your salary information with anyone (which makes sense: it's required on a ton of forms)
To my knowledge, none. There are some laws that exist about some groups (e.g. the IRS) disclosing salary data. But there are whole data-broker businesses built around getting salaries reported to them from employers and using that data.
