Redundant is the Doctrine of Redundant Designation

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In any case involving patent infringement, claim construction is extremely important. In addition to the many US doctrines adopted by Chinese patent law with regard to claim construction, including the doctrine of equivalents, Chinese law has developed a unique doctrine of its own – the doctrine of redundant designation. This doctrine essentially permits the omission of redundant features cited in the independent claims when determining the extent of protection of a patent. However, in a recently decided case, the Supreme People's Court appears to have rendered the doctrine of redundant designation redundant.

The case – Dalian Xinyi Construction Materials v. Dalian Renda New Wall Construction Materials Plant (Xinyi v. Renda) – involved a utility model patent seeking protection for a concrete component consisting of a cylinder body and cylinder ends. The body and ends of the cylinder in question are both made of at least two layers of glass fibre cloth, with an inorganic adhesive concrete material in between. In the alleged infringing product, on the other hand, the cylinder body is made of only one layer of glass fibre cloth, which is embedded in the inorganic adhesive concrete materials, while the cylinder ends are made of only concrete materials without any glass fibre cloth.

Upon comparing the patented and the alleged infringing products, and applying the doctrine of redundant designation, the trial court (the Intermediate People's Court of Dalian City) reached a conclusion of infringement. This was later affirmed by the appellate court (the High People's Court of Liaoning Province). According to the trial court, (i) the cylinder body plays a more important role in the patent than the cylinder ends, thus the cylinder body is an indispensable feature, implying that the cylinder ends are a redundant feature, which can be omitted when deciding the scope of patent protection; and (ii) in accordance with the 'function-way-result test', the alleged product's cylinder body, with one layer of glass fibre cloth, is equivalent to the patent's cylinder body with two layers of fibre cloth. The Supreme People's Court in 2004 granted the petition of certiorari, reheard the case de novo, and rendered its opinion on August 22, 2005.

In its opinion, the Supreme People's Court pointed out that the description of the cylinder ends should not be omitted, because it is also an indispensable feature, and therefore, should not be redundant. The Supreme Court held that the doctrine of redundant designation should not be applied indiscriminately, and indicated that all technical features cited in the independent claims of a patent should be deemed indispensable and should not be omitted. As for the cylinder ends in question, the Court indicated its belief that the alleged product is neither the same as nor equivalent to the patented product. The Court extended its opinion to the cylinder body, indicating it's belief that the alleged product's cylinder body with one layer of glass fibre cloth is not equivalent to the patent's cylinder body with “at least two” layers of fibre cloth.

This is the first time that the Supreme People's Court has explicitly stated its own opinion on the 'doctrine of redundant designation', which developed out of the somewhat controversial practice, adopted by various courts, of adjudicating patent infringement cases. Those in support of this doctrine argue that the underlying idea is to protect inventors who have limited experience in drafting patent documents. The belief is that redundant features cited in independent claims may unduly limit the scope of the claims and the patentee's rights. The counter argument is that this doctrine brings uncertainty to the scope of claims and the extent of patent protection, and is therefore damaging to the public interest.

In 2001, the Beijing High People's Court discussed this doctrine in one of its judicial interpretations, detailing, in addition to other factors, the doctrine's principle and application. In particular, it prescribed that the 'doctrine of redundant designation' should not be applied by the court on its own initiative, but rather at the request of the plaintiff and on the basis of relevant evidence. In 2003, the Supreme People's Court issued a draft (conference discussion version) judicial interpretation on patent infringement adjudication where the doctrine of redundant designation was not listed, indicating that no final agreement had been reached on the application of this doctrine.

In the Xinyi v. Renda case, the Supreme People's Court emphasized the public interest, declaring that the claims define the scope of the patent rights and keep the public clearly informed by displaying to the public all the technical features of a patent. Furthermore, only the certainty of the legal status of a patent's technical features ensures the stability of the legal rights of the inventors and the public. We can therefore reasonably expect that the doctrine of redundant designation, which lends uncertainty to the legal status of some technical features of claims, will likely be abandoned in Chinese patent law in the future.