These entries are queried from radb.net using whois, you can try my project getting these.
:AS23776 route: 121.100.8.0/21 descr: NEC Corporation. AS Block(AS23776) X-Keiro: system-mgmt [at] itsmc.jp.nec.com origin: AS23776 notify: system-mgmt [at] itsmc.jp.nec.com mnt-by: MAINT-AS23776 changed: keiya-tanaka [at] nec.com 20230524 source: JPIRR rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route: 203.179.16.0/20 descr: NEC Corporation. AS Block(AS23776) X-Keiro: system-mgmt [at] itsmc.jp.nec.com origin: AS23776 notify: system-mgmt [at] itsmc.jp.nec.com mnt-by: MAINT-AS23776 changed: keiya-tanaka [at] nec.com 20230524 source: JPIRR rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route6: 2401:2680::/32 descr: NEC Corporation. AS Block(AS23776) X-Keiro: system-mgmt [at] itsmc.jp.nec.com origin: AS23776 notify: system-mgmt [at] itsmc.jp.nec.com mnt-by: MAINT-AS23776 changed: keiya-tanaka [at] nec.com 20230524 source: JPIRR rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source