These entries are queried from radb.net using whois, you can try my project getting these.
:AS3408 route: 47.19.103.0/24 descr: AMC Networks origin: AS3408 mnt-by: MAINT-AS27506 changed: aday [at] lightower.com 20180728 source: RADB last-modified: 2023-11-13T15:54:23Z rpki-ov-state: valid route: 64.46.34.0/24 descr: Clueful.net origin: AS3408 mnt-by: MAINT-CLUEFUL changed: noam [at] noam.com 20010917 source: ALTDB rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route: 192.243.38.0/24 descr: Clueful.net origin: AS3408 mnt-by: MAINT-CLUEFUL changed: noam [at] noam.com 20010927 source: ALTDB rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route: 198.96.22.0/24 descr: Clueful.net origin: AS3408 mnt-by: MAINT-CLUEFUL changed: hostmaster [at] clueful.net 19991023 source: ALTDB rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route: 203.20.53.0/24 descr: Clueful.net origin: AS3408 mnt-by: MAINT-CLUEFUL changed: noam [at] noam.com 20010917 source: ALTDB rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route6: 2604:9400::/32 descr: AS3408OpenRangeCommunications origin: AS3408 mnt-by: ORC-NET-1-MNT changed: frank.delung [at] level3.com 20100807 source: LEVEL3 rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source