This case pertains to an Australian patent application related to a VHH antibody. According to the original claim 1, the complementary determining regions (CDRs) comprise: CDR1 with an amino acid sequence represented to one of SEQ ID NO. 1-8, CDR2 with an amino acid sequence represented to one of SEQ ID NO. 9-16, and CDR3 with an amino acid sequence represented by one of SEQ ID NO.17-23. That is, the initial scope of this patent includes 8*8*7=448 antibodies.

In the first office action from the Australian Patent Office, the examiner considered that the protection scope of the original claims was overly broad and lacked sufficient support from the specification. The reasoning was that the specification only provided exemplary data on the binding ability of 8 antibodies, whereas claim 1 involved a large number of antibodies composed of different CDRs arbitrarily, and the binding ability and effect of these antibodies were difficult to predict. Therefore, the applicant was required to limit the scope to only include the 8 antibodies involved in the specification.

The client's initial response to this office action highlighted that it did not pertain to inventiveness, but rather to the issue of the claims' protection scope being excessively broad and unsupported by the specification. Accordingly, it was suggested that claim 1 could be omitted.

Although the client did not explicitly request to pursue the broadest possible protection scope, our agent still sought to persuade them to aim for the maximum protection during this response for the following reasons: 1. Valuing the response opportunity. As this is the first response attempt, we were determined to make the most of it. Even if the argument was not accepted by the examiner, we would have no regrets, as it would not hinder further communication with the examiner. 2. Seeking to enhance professional expertise. As the agent, cases challenged on the grounds of lacking novelty and/or inventiveness. We have substantial experience and strategies for addressing issues related to novelty and inventiveness. However, for other types of issues (such as lack of support, unclearness, purely intellectual activities, etc.), each case requires a unique approach. We aim to gather viable argument strategies for future reference, viewing this as an excellent learning opportunity. Therefore, our agent subsequently communicated with the client and proposed not to modify the claims, instead striving to maintain as large a scope as possible. This proposal was accepted by our client.

In the communication with the foreign agency, the attorney confirmed that it is feasible to explain the binding ability of the remaining antibodies by supplementing experimental data, but our client feedback that they do not have experimental data on the binding ability of the remaining antibodies. Therefore, to counter the objection of “overly broad scope of protection”, we were compelled to argue that “the skilled person in the art can expect that the antibodies covered by claim 1 all have the expected binding properties based on the information given by the specification and the conventional technical means.” This point represented a significant challenge in our response. The response strategies are as follows:

（1）Argue “reasonable expectation” based on the information disclosed by the original specification. We employed a tabular format to sort out the amino acid sequences of each CDR region for the 8 antibodies in the embodiment. This approach clearly demonstrated to the examiner certain rules: antibody A and antibody B have the same CDR3 sequence but differ in CDR1 and CDR2, yet they exhibit similar binding capabilities. Similarly, antibody C and antibody D have nearly identical CDR1 region (with just one amino acid substitution) but differ in CDR2 and CDR3, yet both antibodies have similar binding abilities. Likewise, antibody E and antibody F have basically the same CDR2 region (with two amino acid substitutions) but differ in CDR1 and CDR3, and they also demonstrate similar binding abilities. Based on the analysis of the CDR region sequences of the 8 antibodies in the embodiment, it can be seen that keeping one CDR constant while altering the other two CDRs does not significantly impair the binding performance of the antibody in this invention.

（2）Citing authorized Australian patents to illustrate the feasibility of granting a broader scope. Through searching, reviewing and analyzing the application and authorization texts of similar antibodies of Australian patents, we found that the Australian Bureau’s examination scale for “whether the claims are supported by the specification” is quite stringent. Most of the authorization texts showed applicants finally compromised and narrowed the scope to a few antibodies in the specification embodiment. But there were a small number of authorized patents whose antibody scope far exceeded the antibody scope exemplified by the specification embodiment. Finally, our agent cited four representative authorized patents. To ease the examiner's workload, we provided a brief analysis of these four patents, illustrating that granting patents for “antibodies defined by CDR combinations”with a scope broader than a few exemplified antibodies is not unprecedented in Australia. These patents' broad scope indirectly indicates that a person skilled in the art, based on the examples provided, could predict that antibodies defined by CDR combinations would possess the desired binding properties.

Finally, after the first response, the examiner accepted our agent’s statement and authorized this patent.