Summary
    The present case relates to the problem of the criterion of the examiner in China for judging "support from the description" of claims of an application in the field of biology and chemistry. When responding to Office Actions and requesting reexamination, the applicant did not mechanically follow the examiner's comments; but referring to our suggestions made some claim amendments to gradually narrow the protection scope and also some powerful arguments by virtue of a prior document to prove that pending claims are supported by description.

Background
    At present, Chinese examiners adopt a strict criterion on the "support" matter of claims of an application in the field of biology and chemistry. Generally, only those claims (or technical features therein) which are proved by experimental examples in description would be accepted by Chinese examiners. With regard to the claims which relate to amino acid sequence, in general, only the specific amino acid sequence which is proved to have the corresponding effects is allowed for protection. In other words, defining amino acid sequence in an open manner, for example, in the format of "having..." or "comprising...", would be un-acceptable to Chinese examiners.

    A main reason why such a strict criterion is adopted seems to be that examiners believe that any minor change in amino acid chain would possibly affect the function of the resulted protein. If adding one or more additional amino acids on one end or both ends of a specific amino acid sequence, the amino acid sequence would necessarily change, and accordingly, the function of the resulted protein would possibly change. However, according to our opinion, not all the patent applications related with an amino acid sequence require the amino acid chain to form a protein with a particular function. For such a patent application, it needs more consideration whether it is necessary to require applicant to define the specific amino acid sequence in claims.

    The present case is a representative example.

Process
    (1) The examiner in the first Office Action indicated that the feature "the polypeptide comprises a heparin-binding domain" in claim 1 is not supported by description.

    The purpose of the invention is to provide a method of isolating glycosaminoglycans capable of binding to a protein having a heparin-binding domain. In the said method, a polypeptide is used to contact with a mixture comprising glycosaminoglycans such that polypeptide-glycosaminoglycan complexes are allowed to form and then the glycosaminoglycans could be isolated from the mixture. In the originally filed claim 1, the polypeptide is defined as comprising a heparin-binding domain.

    In the issued OA1, the examiner held that, the person skilled in chemistry could hardly predict whether there exist polypeptides of other kinds which are also in a position to solve the technical problem of the present application and achieve the same technical effect, besides the polypeptides of SEQ ID NO.: 1 disclosed in the description. For this matter, we held a different opinion and suggested that the applicant could make some arguments based on the disclosure of the polypeptide sequences SEQ ID NOs: 1-13 and 17 in the description, without amendments, in an attempt to pursue a broad scope. The applicant accepted our suggestions.

    When responding to OA1, we argued according to the applicant's instruction that, since a number of heparin binding domain sequences such as SEQ ID NO: 1-13 and 17 are disclosed in the description, the skilled person is provided with adequate information to predict that all the polypeptides having a heparin-binding domain could be used to solve the technical problem of the present application and achieve the same technical effect.

    (2) In OA2 and a subsequent OA3, the examiner still believed that claim 1 covers a too large scope, and he hoped us to define the polypeptide sequence in claim 1 to be the specific sequence SEQ ID NO: 1 which is validated in the description.

    It is obvious that such an amendment would unduly narrow the protection scope of the present application. As above mentioned, the purpose of the present invention is not to effectuate a particular function of the protein encoded by the specific amino acid sequence. Rather, the invention is to utilize the binding property of the polypeptide with glycosaminoglycans, and the binding property is just derived from the heparin-binding domain comprised in the polypeptide. The description has already proved that SEQ ID NO: 1 is a heparin-binding domain, and adding one or more additional amino acid residues would actually not affect the binding property thereof with glycosaminoglycans. This point would easily occur to the skilled person. When responding to OA2, based on the disclosure of the description, the polypeptide in claim 1 was defined as being or comprising SEQ ID NO: 1, and some extended arguments were made. When responding to OA3, the polypeptide in claim 1 was further defined as consisting of the amino acid sequence SEQ ID NO: 1 and optionally one or more additional amino acids at one or each of the N- and C- terminal ends wherein the number of such additional amino acids is 1-20. The above amendments were made in an attempt to pursue a relatively broader scope.

    (3) Although such amendments were submitted, the examiner still believed that the presence of additional amino acid on one or both end(s) of specific amino acid sequence would affect the resultant function thereof, and thus the examiner rejected the application with a holding that claims lack supporting from the description.

    When reporting the Decision of Rejection, we provided a suggestion, i.e., some prior art documents which prove that the addition of a short amino acid sequence on one end or both ends of a specific amino acid sequence would not affect the exposure of the specific amino acid sequence, and would not hinder it from binding with a target substance.

    Recently, in the request for re-examination, the applicant accepted our suggestion, and instructed us to specifically define the polypeptide in claim 1 as consisting of the amino acid sequence SEQ ID NO: 1 and optionally one or more additional amino acids at one or each of the N- and C- terminal ends wherein the number of such additional amino acids is 1-5. In order to strengthen our arguments, a prior art document was submitted to support our view point that the addition of only 1-5 amino acid residues on the end(s) of a polypeptide chain would not affect the exposure of the core polypeptide chain.