Previous research shows that activist threats lead to corporate policy concessions. We find that the threat of proxy fights is responded to differently based on its credibility. Decomposing proxy fight threats, we find that only credible threats are associated with more leveraged, more innovative, and less acquisitive corporate policies. Management, however, does not respond to noncredible threats. Further, for materialized fights, the market reaction at announcement is also conditional on the credibility of the threats. Overall, not all activist threats are responded to equally by management or the market, and only credible threats achieve disciplinary effects and favorable valuation.