“REFRESHING COMPOSITION FOR OPHTHALMOLOGY” Case [Second Judgment]: A case in which the court affirmed conformance of clarity requirement by the correction to delete the statement which was found to be in non-compliance with the clarity requirement for claims.
In the first judgment, with regard to the statement of claims before the correction “a refreshing composition for ophthalmology comprising ⋯ 0.001 to 10 1/v% chondroitin sulfate or a salt thereof with an average molecular weight of 5000 to 40,000 ⋯”, the issue was whether the meaning of the term “average molecular weight” referred to in the statement of the scope of claims of the present patent is clear or not in terms of whether it means “weight-average molecular weight” or “viscosity-average molecular weight”. (As stated below, there are a lot of court cases in relation to a numerical limitation invention in which whether a unit of measurement is unclear or not became an issue.)
Each numerical value shown in general explanations and working examples in the present patent specification was all measured by “weight-average molecular weight”. However, of existing products (sodium chondroitin sulfate) which can be used for the present invention as described in the Detailed Description of the Invention, the product of Seikagaku Corporation was described as a product with an average molecular weight of about 10,000, about 20,000 and about 40,000 (in fact, each of them was a numerical value of weight average molecular weight), on the other hand, the product manufactured by Maruha Corporation was described as a product with an average molecular weight of about 7,000 (in fact, it was a numerical value of viscosity average molecular weight), and thus the first judgment found the statement of the scope of claims violates the clarity requirement, and revoked the JPO decision that dismissed the request for a trial.
Therefore, the patent holder (ROHTO Pharmaceutical), in a trial for patent invalidation proceeding further carried out at the JPO, filed a request for a correction to delete the description of product manufactured by Maruha Corporation, or, sodium chondroitin sulfate with an average molecular weight of about 7,000 (as stated above, it was actually a numerical value of viscosity average molecular weight), and to replace “an average molecular weight of 5,000 to 40,000” in claims with “an average molecular weight of 20,000 to 40,000″. The second judgment found that it cannot be said that this substantially changes the scope of claims, and found that the scope of the claims after the correction conforms to the clarity requirement, stating that the Corrected Description does not refer to sodium chondroitin sulfate from Maruha Corporation ⋯”.
In this case, the purpose of the correction to delete the description of product manufactured by Maruha Corporation with a “viscosity average molecular weight” (not an average molecular weight) of about 7,000 is “clarification of an ambiguous description” (Article 134-2, Paragraph 1, Item 3 of the Patent Act).
Practically, corrections for the purpose of clarification of an ambiguous description tend to be allowed rather flexibly by the JPO, and are frequently used to resolve the non-compliance with the clarity requirement. In this case, however, since it is unclear whether the term an “average molecular weight” in claims means a “weight average molecular weight” or a “viscosity average molecular weight” even by considering the statements in the Detailed Description of the Invention before the correction, it cannot be found that “weight average molecular weight” is correct, and “viscosity average molecular weight” is incorrect.
Therefore, the following opinion would be acceptable: if a correction is filed on the premise that “weight average molecular weight” is correct, whether to accept the correction should be determined based on the same criteria in the case where the purpose of the correction is clarification of ambiguous description and in the case where the purpose of the correction is correction of errors.
The second judgment, which revoked the JPO decision, was rendered in the case filed by the patent holder seeking revocation of the JPO decision which invalidated the patent on the grounds that the statements in claims after the correction are in non-compliance with the clarity requirement. Since whether or not the correction violates the requirements for corrections was not included in grounds for invalidation, the violation of the requirements for corrections may be at issue in a patent invalidation trial again carried out at the JPO and the third judgment.
Writer: Hideki TAKAISHI
Supervising editor: Kazuhiko YOSHIDA
Contact information for inquiries: h_takaishi@nakapat.gr.jp
Hideki TAKAISHI (The person in charge of this Article)
Attorney at Law & Patent Attorney
Nakamura & Partners
Room No. 616, Shin-Tokyo Building,
3-3-1 Marunouchi, Chiyoda-ku
Tokyo 100-8355, JAPAN