This paper traces the growing acceptance of the more economic approach to IPR and competition law in state practices, and summarizes its characteristics. It then compares how jurisdictions weigh the IPR licensing agreements against competition law in the context of patent pools, which have become critically effective mechanism for both patent enforcement and the deployment of new technology. It further analyzes the major difference found, namely the abuse of dominant position by patent pools, and how to look upon and even harmonize it. It then moves on to study the impact of antitrust violation by patent pools on the cease-and-decease request based on IPR and on the licensing agreements. At the end, three points worthy of further attention will be brought up: the transparency of patent pools toward competition authorities, the need of maintaining comprehensive guidelines on IPR licensing agreements, and the effects that the more economic approach should pursue.