A "disclaimer amendment," as the name implies, is an amendment that excludes a certain technical feature from a claim and that usually uses a negative technical feature, such as "does not comprise …," "does not contain …," and "excludes …," to define the claim.
Among the current Chinese Patent Law and its related provisions, only in the guidance for examination concerning Article 33 of the Chinese Patent Law in section 5.2.3, chapter 8, part II of the Guidelines for Patent Examination, a disclaimer amendment is stated as one of disallowable amendments. As can be seen, such amendments are usually not allowed in a patent examination process.
It is prescribed in the Guidelines for Patent Examination that “If no other numerical value within the initial numerical range of a certain technical feature is described in the initial description and claims, while novelty and inventive step are prejudiced by the contents disclosed in reference documents, or the invention cannot be carried out when said feature adopts certain parts of the initial numerical range, in view of these two situations, the applicant has to use a specific ‘disclaimer’ to exclude said parts from the initial numerical range so that the numerical range of the claimed technical solution does not include said parts obviously as a whole, such amendment shall not be allowed because the amendment has gone beyond the scope of disclosure contained in the initial description and claims, with the exception that the applicant can prove, in accordance with the contents described in the initial application, that the invention cannot be carried out when said feature adopts the ‘disclaimed’ numerical value, or the invention possesses novelty and involves an inventive step when said feature adopts the numerical value after the ‘disclaimer’.” In the Guidelines for Patent Examination, the following specific example is given to illustrate the above situation, “For example, the numerical range in the claimed technical solution is X1 =600-10000, the only difference between the technical contents disclosed in the reference documents and said technical solution is that said numerical range in the former is X2 = 240-1500. As X1 and X2 overlap partially, the claim does not possess novelty. The applicant uses the specific "disclaimer" to amend X1, excluding from X1 the portion that X1 and X2 overlap, i.e., 600-1500, thus, said numerical range of the claimed technical solution is changed to be from X1 > 1500 to X1 = 10000. If the applicant can neither prove that the inventions within the numerical range from X1 > 1500 to X1 = 10000 involve inventive step with reference to those within the X2 = 240-1500 range described in the reference documents based upon the initially disclosed contents and the prior art, nor prove that the invention cannot be carried out when X1 is within 600-1500, such amendments shall not be allowed.” It should be noted: the above-mentioned provisions in the Guidelines for Patent Examination only describe a situation of a disclaimer amendment to a numerical range; however, in practice, a disclaimer amendment is not limited to the exclusion of a numerical range; and, all exclusive amendments are not disclaimer amendments, and only those that exclude from the scope of protection of a claim a technical feature not disclosed in the original application documents are disclaimer amendments. For example, the following premise is mentioned in the above provisions in the Guidelines for Patent Examination: “If no other numerical value within the initial numerical range of a certain technical feature is described in the initial description and claims.” A disclaimer amendment, as one of the disallowable amendments, is strictly subject to the limitation of amendment going beyond the scope. By combining the above provisions in the Guidelines for Patent Examination with practices, it is considered that a disclaimer amendment is acceptable in the following situations:
(1)the reference documents are conflicting application documents;
(2)the reference documents are reference documents that are far from the application in the technical field, the technical problem to be solved, and the inventive concept; and (3)the applicant proves, according to the contents initially disclosed by the application, that it is impossible to carry out the disclaimed technical solution, or the technical solution after the “disclaimer" is novel and inventive in view of the "disclaimed" technical solution.
The first two situations are to take into account that when applying for a patent, an applicant cannot know technical information disclosed in a conflicting application or in a technical field that is far from the technical field to which the application belongs. In order to grant the applicant a reasonable scope of protection on the basis of the technical information that has actually been disclosed, the applicant is allowed to exclude a technical feature not disclosed in the original application documents by using the specific "disclaimer." In the third situation, it needs to prove the above “it is impossible to carry out …” and “… novel and inventive” based on evidence limited to the contents of the original application documents and the prior art. This is equivalent to that the applicant denies the contents of the application documents written by the applicant itself. Therefore, in practice, the probability of a successful disclaimer amendment in this situation is very low.
In summary, the current allowance of "a disclaimer amendment" is substantially limited to amendments made to overcome a novelty defect in the abovementioned situations, whereas it is difficult for an amendment made to overcome an inventiveness defect to be allowed.
