“Recent IP High Court Case Denying the Doctrine of Equivalents for the Numerical Limitation Invention,” by Yasuhiro Sato (The Invention 2025 No.5)

Yasuhiro Sato wrote an article published in The Invention 2025 No.5. Yasu’s article, “Recent IP High Court Case Denying the Doctrine of Equivalents for the Numerical Limitation Invention,” discusses a significant Intellectual Property High Court decision regarding numerical limitation inventions. The court ruled that an accused product does not infringe on a patent when the claim specifies a certain numerical parameter as an integer value (e.g., “molecular weight of 700 or more”), even if the product’s value (699.91848) would meet the claim limitation after rounding.