Doctrine of Equivalents in Japan Yoshiaki SHIBATAJudgeTokyo District Court

April 6, 2018

1 “Ball Spline Case” - five requirements

　 Supreme Court Judgment (February 24, 1998, ”Ball Spline case”)

　 The Supreme Court of Japan affirmed the doctrine of equivalents and stated five requirements

1 “Ball Spline Case” 　 - five requirements　“ Even if there is a part in elements of a patent claim, which is literally different from the accused products or process (“products”), 　① if this part is not the essential part of the 　patented invention ； (NON ESSENTIAL PART)　② if the purpose of the patented invention can be achieved and identical function and effect can be obtained by replacing this part with a part in the accused products; (INTERCHANGABILITY)

1 “Ball Spline Case” - five requirements

　③ if a person ordinarily skilled in the art could easily come up with the idea of such replacement at the time of the production of the accused products; (EASE OF INTERCHANGEABILITY)　④ if the products are not identical to the technology in the public domain at the time of the application of the patented invention or could not be easily conceived by this person at that time; (NON OBVIOUSNESS)

1 “Ball Spline Case” - five requirements

　⑤ if there were no special circumstances such as the fact that those products had been intentionally excluded from the scope of the patent claim in the patent application process; (NO SPECAUL CIRCUMSTANCES)

such products should be regarded as equivalent with the elements of the patent claim and fall within the scope of the technological scope of the patented invention.”

2 After the “Ball Spline Case”Fifth requirement no “special circumstances”

(no intentional exclusion)

The applicant didn’t state in the scope of claims a feature that could have been easily conceived at the time of filing a patent.

Whether it can be said that special circumstances exist based on this fact alone?

If no, in what cases can you say there are special circumstances?

3 “Maxacalcitol Case”

Supreme Court judgement(March 24, 2017, “Maxacalcitol Case”)

3 “Maxacalcitol Case” “In consequence, even in a situation where the scope of patent claims written by the patent applicant did not mention the structure for Competing Products or Processes different in part from the structure stated in the scope of claims while the applicant was able to easily conceive the structure for such Competing Products or Processes at the time of filing the application,

3 “Maxacalcitol Case”the mere fact of such omission in the scope of the patent claims does not infer that the Competing Products or Processes were intentionally excluded from the scope of patent claims in the course of filing the application for the patented invention or that there are other special circumstances.”

3 “Maxacalcitol Case”“Intentional exclusion of Competing Products or Processes from the scope of patent claims in the course of filing an application for a patented invention or the existence of other special circumstances should be ascertained if the applicant is objectively and visibly determined to have indicated his/her intension of omitting statements concerning Competing Products or Processes in the scope of the patent claims in a situation described below,

3 “Maxacalcitol Case”while recognizing that the structure for the Competing Products or Processes could substitute for the structure stated in the scope of the patent claims: the applicant knew the existence of such Competing Products that contain certain parts that are different from the parts in the structure stated in the scope of the patent claims; and the applicant was easily conceive the structure for such competing Products or Processes at the time of filing the application in connection with said differences”

Thank you !