Imputation of missing inventor country codes in worldwide patent data

The file ctry_inv_person.txt contains identifiers for patent first filings and the inventor (corresponding to appln_id and person_id in PATSTAT) and the country of the inventor. Missing country codes have been imputed from equivalents and other second filings or from information on the county of applicants. It is possible to select certain types of first filings based on column 'type'. For example, Paris Convention priority filings can be retrieved by specifying type='priority'. The field 'source' indicates where the information on inventors' location comes from : 1 = information available from the patent itself, 2 = information availabe from the earliest direct equivalent, 3 = information available from the earliest subsequent filing, 4 = applicants' location from the patent itself, 5 = applicants' location from earliest direct equivalent 6 = applicants' information from earliest subsequent filing. The following 52 patent offices are browsed (EU27 + OECD + BRICS + EPO + WIPO): AL,AT,AU,BE,BG,BR,CA,CH,CL,CN,CY,CZ,DE,DK,EE,EP,ES,FI,FR,GB,GR,HR, HU,IB,IE,IL,IN,IS,IT,JP,KR,LT,LU,LV,MK,MT,MX,NL,NO,NZ,PL,PT,RO,RS,RU,SE,SI,SK,SM,TR,US,ZA.文件ctry_inv_person.txt包含专利首次申请标识与发明人标识（对应PATSTAT数据库中的appln_id与person_id），并记录了发明人所属国家。缺失的国家代码已通过等效申请、其他后续申请或申请人所在国家的相关信息完成补全。可通过‘type’列筛选特定类型的首次申请，例如通过指定type='priority'，即可检索巴黎公约优先权首次申请。‘source’字段用于说明发明人所在地信息的来源：1 = 专利本身自带的相关信息；2 = 最早直接等效申请的信息；3 = 最早后续申请的信息；4 = 专利本身记录的申请人所在地信息；5 = 最早直接等效申请记录的申请人所在地信息；6 = 最早后续申请记录的申请人信息。本次覆盖的52个专利机构包括（欧盟27国 + 经合组织 + 金砖国家 + 欧洲专利局 + 世界知识产权组织）：AL、AT、AU、BE、BG、BR、CA、CH、CL、CN、CY、CZ、DE、DK、EE、EP、ES、FI、FR、GB、GR、HR、HU、IB、IE、IL、IN、IS、IT、JP、KR、LT、LU、LV、MK、MT、MX、NL、NO、NZ、PL、PT、RO、RS、RU、SE、SI、SK、SM、TR、US、ZA。