WEEE recycling patents' dataset
Description
The patent dataset analyzed is based on search criteria dealing with WEEE recycling, namely focusing on battery recycling, while a ‘control’ sample is produced where the patent data concern a more generical recycling technical context. Such differentiation is essentially achieved by two different selections from the EPO database Patstat (Spring 2022 ed.), each patent search being based on IPC/CPC classification codes selected from a pool of “green” classification codes. While the dataset regarding the batteries is defined by any of the IPC/CPC H01M6/52 or the IPC/CPC H01M10/54 or the CPC Y02W30/84 individually taken or combined together, documents of the ‘control’ should not be assigned with any of the classification codes defining the batteries recycling. The first step of the patent analysis is focusing on applications including either national authorities or supranational authorities, such as the EPO or the WIPO (both addressed through harmonized filing procedures) to evaluate meaningful trends of patent applications filed starting from yr. 1980 to yr. 2022. Such trends can also be assessed in order to normalize the amount of filing events, i.e. by comparing, for each of the most representative patent authorities, the trend of WEEE specific applications with the trend resulting from the combination of the WEEE applications plus the amount of the applications belonging to the respective control sample, for each trend being the applications filed to the same patent authority. A subsequent step entails assessments based on the EPO definition of simple patent families. Essentially, the same strategy has been adopted for both the ‘WEEE/RAEE’ patent families and the ‘control’. The assessment in each case deals with the analysis of the patent families based on the ranking of IPC and CPC codes, respectively, to highlight those most frequently assigned in the field of batteries recycling. Subsequently, qualitative and quantitative information is provided about the most frequently addressed patent authorities, the most representative players and their affiliation, the patent family dimensions, the forward citations (in terms of number of citing families and national/supranational authorities) for each patent family of the dataset. Eventually a ‘proof of concept’ analytic approach deals with the focusing on the filing strategy of the top players. The same analytic approach could be used in case other kinds of electronic waste recycling should be of interest, for example not focusing on batteries. To such aim, the CPC Y02W30/82 classification code, initially present in several patent documents included in the ‘control’ sample if focusing on the batteries recycling, should be then omitted from the control dataset and be replaced with the IPC/CPC classification codes specific for the batteries recycling. Therefore, the CPC Y02W30/82 could define a new dataset, namely that one specifically regarding the WEEE (non-batteries) recycling.
Files
Steps to reproduce
Upon following the instructions written in the Methodology section and using the datasets' information included in the Data files' section, the reproducibility of our results is straightforward. The main evidences of the whole analysis follow: 1. Considering the materials’ recycling in general and then especially the “WEEE” (essentially battery) recycling and excluding exceptional cases, the number of patent applications has considerably increased after the year 2000, most filing events targeting the Asian patent offices. 2. However, following the normalization of the data based on the count of patent applications, it turns out that the proportion and especially the trend of applications specifically concerning the “WEEE” (batteries) recycling is similar when comparing some of the most representative patent authorities (for example the CNIPA/SIPO, the JPO, the EPO and the WIPO). 3. Most of the patent families specifically concerning the “WEEE” recycling are characterized by the assignment of at least one classification code chosen a priori to define the “WEEE” recycling, being the IPC H01M10/54 (Reclaiming serviceable parts of waste accumulators), assigned to 89,5% of the patent families, while the CPC Y02W30/84 (Recycling of batteries or fuel cells) being assigned to 98% of the patent families, and neither of these two classification codes being assigned to the “control” sample, including more than 200 thousand patent families. 4. Almost 75% of patent families specifically concerning the “WEEE” recycling correspond to patent applications which include at least one application filed to CNIPA/SIPO. Moreover, several Chinese applicants, such as the Chinese Academy of Science, the Central South University plus several companies score the highest ranking based on the number of patent families owned. However, most of such families correspond to patent applications filed exclusively to the CNIPA/SIPO. Other Asian players, such as Toyota Motor Co., or Sumitomo, have instead filed a multiplicity of patent applications to different authorities, such difference reflecting a completely different approach to the legal means available for protecting of an invention. 5. Upon analyzing the forward citations of the retrieved patent documents it appears as if, on average, each patent family were cited by 5 ÷ 6 patent families originating from subsequently filed applications and such proportion of forward citations seems substantially identical when comparing the “WEEE” dataset and the “control”. However, the average frequency of FWD citations might vary consistently depending on the patent authority to whom the cited patent applications are filed. For example, the ratio between the USPTO and the CNIPA/SIPO, each considered as the receiving authority of the patent applications corresponding to the cited family in the dataset specifically concerning the “WEEE” recycling, ranges between 3 and 4.