Though reducing popularity of toehold acquisition in takeovers can suggest a failure of toehold bidding, it can be induced by a self-selection process where bidders gradually learn the pitfalls in toehold acquisition so that only qualified bidders adopt this strategy in the end. This paper uses four efficiency measures to show improvement in toehold performance in takeovers over time, which supports the learning effect in toehold acquisition. Furthermore, institutional holding appears successful in mitigating pitfalls in toehold bidding, which suggests firms with better monitoring quality can be qualified bidders for toehold acquisition.