[AstralStorm]

The third party may be:

- an insurance company demanding a premium because you're well paid

- competitor bidding for your labour anchoring their offer to your current salary

Those are just two cases were it could be harmful. The idea is to make the information available and transparent while still not making it public and still protecting it.

[dawnbreez]

Fair enough. The Glassdoor system may be best here, as mentioned in several other comments.