{"classifier_version":"1.4.0","documentation":"https://rirtracker.com/api/","disclaimer":"This site independently analyzes publicly available Internet number-resource records. It is not affiliated with or endorsed by ARIN, the RIPE NCC, APNIC, LACNIC, AFRINIC, the Number Resource Organization (NRO), or any other Regional Internet Registry. Classifications and hold-expiration dates are evidence-based interpretations and do not constitute confirmation that a resource is available for issuance or transfer.","resource":"AS572","resource_type":"asn","page":"https://rirtracker.com/asn/572/","statistics_now":{"registry":"ARIN","status":"assigned (dated 2014-02-18)"},"current_holder":{"rir":"ARIN","org":"Greater Baltimore Medical Center Inc","handle":"GBMC-2","how":"RDAP, looked up 2026-11-10 18:25 UTC"},"rdap_snapshots":[{"resource_type":"asn","start_key":"0000000000000000000000000000023c","end_key":"0000000000000000000000000000023c","captured_at":"2026-11-10T18:25:41+00:00","reason":"watch","authoritative_rir":"ARIN","handle":"AS572","name":"GBMC-TOW","status":"active","org_handle":"GBMC-2","org_name":"Greater Baltimore Medical Center Inc","registration_date":"2014-02-18T14:47:39-05:00","last_changed_date":"2014-02-18T14:47:39-05:00","rdap_url":"https://rdap.arin.net/registry/autnum/572"},{"resource_type":"asn","start_key":"0000000000000000000000000000023c","end_key":"0000000000000000000000000000023c","captured_at":"2026-11-03T18:25:13+00:00","reason":"watch","authoritative_rir":"ARIN","handle":"AS572","name":"GBMC-TOW","status":"active","org_handle":"GBMC-2","org_name":"Greater Baltimore Medical Center Inc","registration_date":"2014-02-18T14:47:39-05:00","last_changed_date":"2014-02-18T14:47:39-05:00","rdap_url":"https://rdap.arin.net/registry/autnum/572"},{"resource_type":"asn","start_key":"0000000000000000000000000000023c","end_key":"0000000000000000000000000000023c","captured_at":"2026-10-29T19:48:59+00:00","reason":"watch","authoritative_rir":"ARIN","handle":"AS572","name":"GBMC-TOW","status":"active","org_handle":"GBMC-2","org_name":"Greater Baltimore Medical Center Inc","registration_date":"2014-02-18T14:47:39-05:00","last_changed_date":"2014-02-18T14:47:39-05:00","rdap_url":"https://rdap.arin.net/registry/autnum/572"},{"resource_type":"asn","start_key":"0000000000000000000000000000023c","end_key":"0000000000000000000000000000023c","captured_at":"2026-10-24T18:24:11+00:00","reason":"watch","authoritative_rir":"ARIN","handle":"AS572","name":"GBMC-TOW","status":"active","org_handle":"GBMC-2","org_name":"Greater Baltimore Medical Center Inc","registration_date":"2014-02-18T14:47:39-05:00","last_changed_date":"2014-02-18T14:47:39-05:00","rdap_url":"https://rdap.arin.net/registry/autnum/572"},{"resource_type":"asn","start_key":"0000000000000000000000000000023c","end_key":"0000000000000000000000000000023c","captured_at":"2026-10-18T18:21:39+00:00","reason":"watch","authoritative_rir":"ARIN","handle":"AS572","name":"GBMC-TOW","status":"active","org_handle":"GBMC-2","org_name":"Greater Baltimore Medical Center Inc","registration_date":"2014-02-18T14:47:39-05:00","last_changed_date":"2014-02-18T14:47:39-05:00","rdap_url":"https://rdap.arin.net/registry/autnum/572"},{"resource_type":"asn","start_key":"0000000000000000000000000000023c","end_key":"0000000000000000000000000000023c","captured_at":"2026-10-13T18:21:26+00:00","reason":"watch","authoritative_rir":"ARIN","handle":"AS572","name":"GBMC-TOW","status":"active","org_handle":"GBMC-2","org_name":"Greater Baltimore Medical Center Inc","registration_date":"2014-02-18T14:47:39-05:00","last_changed_date":"2014-02-18T14:47:39-05:00","rdap_url":"https://rdap.arin.net/registry/autnum/572"},{"resource_type":"asn","start_key":"0000000000000000000000000000023c","end_key":"0000000000000000000000000000023c","captured_at":"2026-10-10T17:49:55+00:00","reason":"watch","authoritative_rir":"ARIN","handle":"AS572","name":"GBMC-TOW","status":"active","org_handle":"GBMC-2","org_name":"Greater Baltimore Medical Center Inc","registration_date":"2014-02-18T14:47:39-05:00","last_changed_date":"2014-02-18T14:47:39-05:00","rdap_url":"https://rdap.arin.net/registry/autnum/572"}],"transfers":[],"events":[{"event_id":"ad7a06a8328ea4e9","registry":"ARIN","report_date":"2013-11-15","source":"statistics","raw_action":"NOT_IN_ARIN_ISSUED","raw_line":null,"resource_type":"asn","resource":"AS572","start":572,"end":572,"classification":"REMOVED_REASON_UNKNOWN","classification_label":"Removed (return, revocation or reclamation not publicly distinguishable)","confidence":"STRONG_INFERENCE","source_rir":null,"recipient_rir":null,"source_organization":null,"recipient_organization":null,"inventory_effect":"Possible future reissue candidate after hold","inventory_effect_code":"HOLD_CANDIDATE","provisional":false,"classifier_version":"1.4.0","classified_at":"2026-10-13T23:58:39+00:00","page":"https://rirtracker.com/asn/572/#e-ad7a06a8328ea4e9","report_page":"https://rirtracker.com/arin/reports/2013-11-15/","evidence_url":"https://rirtracker.com/api/v1/resources/asn/572.json","observed":"AS572 assigned on 2013-11-15, reserved on 2013-11-16","hold":{"hold_rule_source_url":"https://www.arin.net/resources/guide/request/#reissuing-returned-revoked-and-reclaimed-resources","hold_rule_months":6,"estimated_hold_end":"2014-05-15","availability_statement":"Possible reissue candidate after this date; not confirmed available"},"explanation":"Removed from active registration. ARIN-Issued didn't list this; the tracker found it by comparing ARIN's daily statistics. ARIN's statistics show it assigned (dated 2009-07-21) on 2013-11-14 and reserved on 2013-11-16. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed ASNs for 6 calendar months before reissuing them, so the estimated hold end is 2014-05-15. This does not confirm availability.","evidence":[{"type":"statistics_diff","url":"https://ftp.arin.net/pub/stats/arin/archive/2013/delegated-arin-extended-20131116.gz","retrieved_at":"2026-10-12T20:07:42+00:00","summary":"Not listed in ARIN-Issued; found by comparing ARIN's daily statistics: AS572 assigned on 2013-11-15, reserved on 2013-11-16"},{"type":"delegated_before","url":"https://ftp.arin.net/pub/stats/arin/archive/2013/delegated-arin-extended-20131114.gz","retrieved_at":"2026-10-12T20:07:31+00:00","summary":"ARIN delegated statistics 2013-11-14 (produced 2013-11-14T06:06:47+00:00), before the report: assigned (dated 2009-07-21)"},{"type":"delegated_after","url":"https://ftp.arin.net/pub/stats/arin/archive/2013/delegated-arin-extended-20131116.gz","retrieved_at":"2026-10-12T20:07:42+00:00","summary":"ARIN delegated statistics 2013-11-16 (produced 2013-11-16T06:06:12+00:00), after the report: reserved"}]}],"classification_history":{"ad7a06a8328ea4e9":[{"raw_change_id":266723,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.3.0","classified_at":"2026-10-13T04:39:17+00:00","current":0,"public_explanation":"Removed from active registration. ARIN-Issued didn't list this; the tracker found it by comparing ARIN's daily statistics. ARIN's statistics show it assigned (dated 2009-07-21) on 2013-11-14 and reserved on 2013-11-16. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed ASNs for 6 calendar months before reissuing them, so the earliest estimated hold expiration is 2014-05-15. This does not confirm availability."},{"raw_change_id":266723,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.3.1","classified_at":"2026-10-13T08:11:38+00:00","current":0,"public_explanation":"Removed from active registration. ARIN-Issued didn't list this; the tracker found it by comparing ARIN's daily statistics. ARIN's statistics show it assigned (dated 2009-07-21) on 2013-11-14 and reserved on 2013-11-16. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed ASNs for 6 calendar months before reissuing them, so the earliest estimated hold expiration is 2014-05-15. This does not confirm availability."},{"raw_change_id":266723,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.3.2","classified_at":"2026-10-13T14:54:52+00:00","current":0,"public_explanation":"Removed from active registration. ARIN-Issued didn't list this; the tracker found it by comparing ARIN's daily statistics. ARIN's statistics show it assigned (dated 2009-07-21) on 2013-11-14 and reserved on 2013-11-16. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed ASNs for 6 calendar months before reissuing them, so the earliest estimated hold expiration is 2014-05-15. This does not confirm availability."},{"raw_change_id":266723,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.4.0","classified_at":"2026-10-13T23:58:39+00:00","current":1,"public_explanation":"Removed from active registration. ARIN-Issued didn't list this; the tracker found it by comparing ARIN's daily statistics. ARIN's statistics show it assigned (dated 2009-07-21) on 2013-11-14 and reserved on 2013-11-16. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed ASNs for 6 calendar months before reissuing them, so the estimated hold end is 2014-05-15. This does not confirm availability."}]},"arin_statistics_now":{"status":"assigned (dated 2014-02-18)"}}