Case Studies

Case Studies

Case Studies from
CAFC Decisions

The CAFC (U.S. Court of Appeals for the Federal Circuit) hears all appeals involving patent law from the courts of first instance and the PTO. The United States is a common law jurisdiction, and a large number of patent cases are filed each year (depending on the year, about 4000 cases, over 40 times more than in Japan). The CAFC has been the busiest and the most powerful court in the world over the last four decades. The U.S. Supreme Court also renders important IP decisions. The decisions of the CAFC and the U.S. Supreme Court can influence patent law in Japan and other countries. Judgments of patent infringement and validity tend to be the same across the courts of various countries when the scope of the patented claims and the accused products is the same. Therefore, it is very important to study the logic of the case decisions from the United States, which provides many more court decisions than Japan does.


Consequently, Milbank, Tweed, Hadley & McCloy LLP and our office have for over 18 years studied U.S. case law, with a focus on CAFC decisions, and introduced key cases to Japanese readers in the monthly publication "The Lawyers". To date, we have reported on over 700 cases. Currently, we are cooperating with Morgan, Lewis & Bockius LLP on this project.

Reports of Japanese Court Decisions

In 2005 the Tokyo District Court and the Osaka District Court were granted exclusive jurisdiction as courts of first instance for patent infringement cases in Japan, and the Intellectual Property (IP) High Court was established in Tokyo as the appellate court.

In addition, the IP High Court holds exclusive jurisdiction with regards to decisions and appeals for the Japan Patent Office (JPO). Thus a system in which all important intellectual property cases converge on the IP High Court has been constructed, and the IP High Court has been able to set forth unified opinions with regard to interpretation of the Patent Act, claim interpretation, evaluation of damages, and the like. The IP High Court has become an IP opinion leader through cases, and has increased the predictability of patent cases. At the same time, decisions of the IP High Court that review decisions of the Japan Patent Office have provided a large impact on the JPO practice.

Despite Japan’s status as a civil-law country, the IP High Court is having a remarkable impact on patent practice and business as mentioned above. In response, Ohtsuka Patent Office advises and shares information with our clients on court decisions in a timely manner.