AstraZeneca decision is of significance from the perspective of patent application under competition law. This decision has served as momentum to analyze patent application strategy to delay generic drugs` entrance into the market and impeding activities against competitors` R&D. Such strategy and activities were found to be potentially anti-competitive by “the Pharmaceutical Sector Inquiry Final Report” of the European Commission. AstraZeneca decision confirmed the principle of competitive law theory that a patent application could be abuse of a dominant position under TFEU Art. 102, if the patent application influences directly the competitiveness of a relevant market. In addition, it was confirmed by recent decisions of the General Court of the European Union (2010) and Court of Justice of the European Union (2012) as well that responsibilities under competition law are not exempted even if there is a legal right from patent law. However, in order to impose liability, it should be proven the fact that price competition is lessened in the market or damage that competitors` innovative incentive is impeded under competition law. Currently, the pharmaceutical industry is still affected by strong and close probes by the Pharmaceutical Sector Inquiry. It is partially because of the fact that the pharmaceutical industry is a main target of competition law enforcement and partially because of influence of AstraZeneca and Boehringer-Ingelheim. In Korea, in the pharmaceutical industry, since multi-national companies exercise strong power in technology, domestic companies are situated as “absolutely weak market players.” Even large domestic pharmaceutical companies usually produce generic drugs. Therefore, it is more likely that unfair transactions in terms of patents can take place between multi-national companies and domestic companies or between domestic large companies and domestic small companies. In particular, it is high time to monitor and regulate abuse of patents by multi-national companies and domestic large companies. For these reasons, European Commission(EC)`s pharmaceutical sector inquiry, EC`s investigation and regulation, the AstraZeneca decision of the General Court and Court of Justice of European Union is very suggestive to and policies in patent law and competition law in Korea.