We are internally transparent about salaries and equity, and use a transparent salary formula to base salary on role, skills, location etc instead of 'negotiation skills.' We also share as much as possible of our organization's 'handbook' openly: https://github.com/Wevolver/Handbook

Transparency is a relative term, and full transparency is an illusion, at best. I suggest companies don't use transparency as a core value because of this assertion.

True it's relative. I think transparency is an approach. An approach that helps create a healthy workplace and contributes to more productive and happier people. (Also we have not stated that we are fully transparent. Transparency is hard, but I strongly believe in the approach)