Ask HN: How to reduce liability for security researchers?

I realize this question is targeted to U.S. citizens but please feel free to chime in.

[1] Have you ever come under legal threat from a Corporation or Entity after disclosing an exploit? [2] Were you acting on behalf of yourself or your employer? [3] How was this transaction then handled? [4] Is their an Entity (LLC, INC, etc) that is better than the other as far as personal liability concerns?