One factor that keeps these negotiated rates from becoming public is that a lot (actually, almost all) of these contracts signed between hospitals and insurers have a gag order of sorts built into the contract by the hospital. These gag orders prevent the insurer from making the hospital's rates public, and what's more, the terms of these contracts usually forbid insurers from even revealing the existence of these gag orders. Believe me, insurers would love to be able to steer policyholders towards cheaper and higher quality -- better value -- care, but these gag orders make it almost impossible for them to do so. It's an incredibly screwed up system all around, and everyone's complicit -- it's not just the insurers and other payers.