This article was first published by the International Law Office, a premium online legal update service for major companies and law firms worldwide. Register for a free subscription.

A patent's scope is defined by the language of the claim. Due to the polysemy of language, a term may have different meanings to different people. Divergent interpretations of a term can influence a claim's scope and affect the determination of infringement or patent validity. Therefore, disagreements and debates regarding claim constructions always exist in patent litigation.

Legal background

Article 58(4) of the Patent Act stipulates that the "scope of the protection conferred by an invention patent is determined by the claim(s), and the description and drawing(s) may be considered as a reference in the interpretation of the claim(s)".

Nevertheless, different principles are adopted in patent examination and litigation. According to the patent examination guidelines currently in force, the 'broadest reasonable interpretation' principle should be adopted in claim construction – namely, "the interpretation of the claims shall, in principle, give the terms of the claims a most extensive and reasonable meaning, and be consistent with the disclosure of the specification". Conversely, the patent infringement assessment guidelines stipulate that the 'presumption of validity' principle should be adopted in claim construction. Thus, in patent litigation, if a term in a claim has multiple interpretations, it should not be interpreted in the broadest reasonable manner. Instead, such term should be interpreted under the presumption that the claim is valid, without adopting an interpretation that may invalidate the claim.

Consequently, what kind of principles should be adopted in patent invalidation proceedings (including their subsequent administrative litigation)? The Supreme Administrative Court expressed its opinion in this regard in its 108 Pan-Zhi 486 administrative ruling of 7 October 2019.

Facts

This case was an administrative litigation regarding a patent invalidation proceeding. In the case, the Supreme Administrative Court did not adopt the presumption of validity principle in claim construction. Rather, the court ruled in a way that was unfavourable to the patentee based on the broadest reasonable interpretation principle. The patent in dispute pertained to an electronic payment system. The patentee asserted that the feature "execute[d] the client transaction program based on the transaction account information" of Claim 1 and that this should be interpreted as "the client transaction program cannot be executed without the transaction account information". The patentee argued that the prior art documents had not disclosed this feature and thus failed to prove that Claim 1 lacked novelty.

Decision

However, the Supreme Administrative Court held that:

claim construction based on the embodiments of the specification and the drawings should be conducted in the broadest reasonable manner; the claims shall not be limited to the embodiments in the specification and the drawings, except in the case that the specification has clearly stated that the claimed scope is limited to the embodiments and the drawings; the parties concerned should not alter the scope of the patent which is objectively manifested through publication.

Neither the specification nor the claims of the patent in dispute had discussed whether the client transaction programme could be executed without the transaction account information. As a result, the Supreme Administrative Court ruled that there was no room for different interpretations of the feature which "execute[d] the client transaction program based on the transaction account information".

In addition, based on the doctrine of claim differentiation, the patentee asserted that the feature which "execute[d] the client transaction program based on the transaction account information" of Claim 1 was different from the feature which "execute[d] the sale transaction program" of Claim 2. According to the patentee, the feature which "execute[d] the… program based on the transaction account information" was different from the feature which "execute[d] the… program". Thus, these two features should have been interpreted differently. The Supreme Administrative Court rejected the patentee's assertion and stated that:

Claim 2 directly depends [on] Claim 1 and includes all [of] the features of Claim 1… there is no room for the feature 'execute the client transaction program based on the transaction account information' of Claim 1 to be interpreted as 'the client transaction program cannot be executed without the transaction account information', as a result of the language in Claim 2.