In the actual retrieval work, it is also mainly considered from the above aspects: First, the scope of retrieval. Since patentable retrieval often involves invalid retrieval at the same time. Invalid retrieval is the retrieval task of authorized patent. Because the modification of the application documents in the invalidation procedure can only be limited to the claims, and the modification method covers the deletion and merger of the claims and the deletion of the technical scheme, in general, technical features not included in the granted patent claims cannot be added.
Therefore, in order to get better retrieval results in practical work, the scope of invalid retrieval at this time should not be limited to authorized patent claims, but also expand the expectation of claim modification and further expand the scope to the technical scheme after the merger of claims. The second is the retrieval time. Because the existing technology involved in the patent law is based on the filing date (and when the filing date enjoys priority in its related patent documents, it also refers to the priority date), and novelty also adds the concept of conflicting applications, so the retrieval effect is generally not too obvious under strict time conditions. Therefore, in patent retrieval, we can consider not limiting the retrieval time first, and then checking the validity of the publication time after searching for patent documents with appropriate content in a wide time range.