These entries are queried from radb.net using whois, you can try my project getting these.
:AS20423 route: 67.235.50.0/24 descr: EMBARQ HSD origin: AS20423 mnt-by: EMBARQ-MNT changed: casey.w.grover [at] centurylink.com 20100517 source: LEVEL3 rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source route: 67.235.50.0/24 descr: Spectrum Networks proxy registration origin: AS20423 mnt-by: MAINT-AS11404 changed: john [at] vanoppen.com 20111226 #19:00:38Z source: RADB last-modified: 2023-11-13T15:51:16Z rpki-ov-state: not_found # No ROAs found, or RPKI validation not enabled for source