1. Background
Examiners previously relied mainly on novelty and inventive step to prevent claims from having an excessively broad scope. Following the third amendment to the Chinese Patent Law, and particularly in 2011, objections that claims were not supported by the description became more frequent. More office actions challenged claims on the ground that their scope was too broad.
In such cases, an examiner generally compares the technical features of each claim with the relevant embodiments in the description, identifies a feature disclosed in the description but absent from the claim, and concludes that the claim is unsupported because it omits that feature. The applicant is then asked to add the disputed feature to the claim.
2. Analysis and response
Part II, Chapter 2, Section 3.2.1 of the Guidelines for Patent Examination indicates that support for claims, especially independent claims, is closely related to the technical problem to be solved. If the disputed feature is necessary, together with the other claimed features, to solve that problem, a skilled person cannot reasonably predict that the other variants or equivalents covered by the claim would also solve it. A claim omitting that feature is then unsupported.
Conversely, if the disputed feature does not directly contribute to solving the technical problem, and a skilled person can derive and implement the claimed solution from the description, the claim can be supported without adding that feature.
In Chinese patent application No. 200910171949.7, claim 1 concerns an optical filter for compensating for colour shift. It principally uses a green-light absorption pattern of a predetermined thickness on a background layer. The examiner considered that the claim was unsupported because it did not specify the pattern’s arrangement and shape as described in the description. The examiner required the addition of the feature that the green-light absorption stripes are parallel and separated by predetermined intervals.
The applicant explained, first, that the purpose of claim 1 was to minimise colour shift as the viewing angle increased. The pattern’s function was to absorb green light. Whatever its shape or arrangement, it could absorb green light emitted at a predetermined viewing angle. A skilled person could therefore use variations falling within the claim to compensate for colour shift, including the stripe, wave, array and honeycomb patterns disclosed in the description.
Second, the parallel stripes separated by predetermined intervals were only one embodiment. Their shape and arrangement matched the structure of a display used as an example; they were not directly related to minimising colour shift. If the display structure changed, a skilled person could adapt the shape and arrangement of the absorption pattern accordingly.
Claim 1 was therefore supported by the description even though it did not specify the pattern’s shape and arrangement. The examiner ultimately revised the initial position and accepted that the objection had been overcome.
The use of the technical problem in responding to this type of objection remains an approach to be tested and observed in practice. The response discussed here is intended specifically for cases in which support is challenged because of the breadth of the claims.
3. Conclusion
Given the attention paid to support in Chinese examination, applicants should ensure that the scope of the claims corresponds to the disclosure. They should also consider other potential support issues, including consistency between the claims and the description, the support provided by working examples for chemical subject matter, and a sufficiently detailed description of alternative embodiments.
