Chinese patent

In patent claim language, the term ‘comprising’ is generally taken to mean that a claimed device or system includes the listed elements, but they are not necessarily a closed list. In other words, possibly the device or system includes additional elements. Similarly, a method comprising a list of steps may include additional steps not detailed.

There has now been a Chinese ruling to the contrary. Apparently the China Patent Re-examination Board (PRB) has maintained the validity of a patent by interpreting the term “comprising” of the challenged claim as “consisting of”, thereby narrowing the claim scope to avoid prior art.

The case relates to ceramic blasting beads, and an attempt to invalidate Pat. No. ZL200810045235.7 regarding a composition for “ceramic blasting beads” was overturned.

Claim 1 of the patent in question is clear and unambiguous, claiming a ceramic blasting bead comprising various oxides, including ZrO2 and HfO2; Al2O3 or CaO, etc. The petitioner asserted that claim 1 lacks novelty in view of the prior art which discloses all ingredients, and, in addition, two other elements, Y2O3 and CeO2. The patent owner argued that the term “comprising” in Claim 1 is intended to mean “including the following and excluding others” on the basis that the specification disclosed that the motivation of the invention was to provide a solution that excludes Y2O3 and CeO2. The plaintiff disagreed on the necessity to introduce the specification for claim scope determination under Art.59 on the reason that the claims are clear in and of themselves, and thee is no need to look to the specification for further clarification.

Under former Chinese practice, Article 59 teaches that the protection scope of an invention or a utility model patent is confined to what is claimed literally, and the specification may be used to interpret the claims when the claims are unclear by itself. However, in this case, the PRB gave a new understanding of Article 59 that under certain situations, one could also integrate the parts of the specification and the background art of the patent application for claim scope determination, so that the technical solution can be accurately conveyed from the claims, provided that the interpretation does not violate logic and common sense. The PRB further clarifies that introducing the specification for claim scope determination is not restricted to where a claim is unclear.

The Appeal Board reinterpreted Article 59 and concluded that “if a skilled person in the art based on the disclosure of the specification can interpret that certain technical features should be excluded, such exclusion is allowable under the circumstance that the claim terms are not obviously contradictory”.

There is a problem. Section 4.2.1, Ch. 10, Part II of the Chinese Examination Guideline clearly states that “comprising” means that some components which are not indicated in the claim may be further included in a claimed composition. Thus until now, a closed-ended interpretation that excludes features not specifically recited in the claim was untenable. Even though specific PRB decisions are not binding precedents, this decision creates a high degree of uncertainty for those who may wish to invalidate patents based on novelty and/or inventiveness, but may provide another option for patent owners to argue for narrower interpretation of the claims should new prior art be presented during invalidity proceedings that anticipates the originally granted claims.


Since an Australian judge understood the term comprising as limiting, I’ve generally included a paragraph at the end of patent specifications to the effect that the term “comprising” means including but not necessarily to the exclusion of other elements or steps. In other words, the term comprising indicates an open list. A paragraph of this sort can save a lot of ambiguity, but in this case, might have sunk the application.

What is worth noting is that in the Australian case, the judge was a general judge. In this instance, the Chinese board is apparently a dedicated patent forum. In Israel, the patent examiners have a nasty habit of deciding that text of this nature renders the scope of protection ambiguous and request that such paragraphs are removed.

In general, I am not a great fan of boiler-plate text.  The problem is not that people use standard paragraphs. The problem is that they do so without thinking. This case emphasizes that every line of a patent application is a two edged sword in that what is added to widen the scope of a patent claim, invariably widens the prior art that can be cited against the patent as rendering it lacking novelty or inventive step.

Negative claiming is generally frowned upon as being indefinite. However, in this case it seems that if the invention is that the ceramic beads do not contain ceria or yttria, this seems to be what should have been claimed.

There are about 20 applications that I’ve written over the past couple of years that are currently under examination in China and Taiwan. I have to rely on associates for translating my specifications into the local vernacular and in accordance with local case-law. I know what I mean when I write the applications, but do not know what is before the Examiner. Office actions are translated into English for me, and I instruct an associate who responds in Chinese. This is rather like the party game Chinese Whispers. When cases are allowed, I can never really tell whether the claimed invention is what was intended, and recently, where drafting for a China based client, I have the CEO’s personal assistant double check the translation against my original before filing.

Categories: China, claims, Patents, פטנט, פטנטים

1 reply

  1. The term “comprising” has been held to define an exclusive list in Australian patent law as well. Drafters of specifications should use the term “including” to define a non-exclusive list, and reserve the term “comprising” for those circumstances where the list is intended to be exclusive.

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