{"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":"157.194.0.0/16","resource_type":"ipv4","page":"https://rirtracker.com/ip/157.194.0.0-157.194.255.255/","statistics_now":{"registry":"ARIN","status":"allocated (dated 1992-01-24)"},"current_holder":{"rir":"ARIN","org":"UnitedHealth Group Incorporated","how":"ARIN's latest statistics and the latest transfer record"},"rdap_snapshots":[],"transfers":[{"id":44288,"date":"2026-06-11T13:18:21Z","type":"MERGER_ACQUISITION","source_rir":"ARIN","recipient_rir":"ARIN","source_org":"HBO & Co.","recipient_org":"UnitedHealth Group Incorporated","range":"157.194.0.0/16","log":"ARIN"}],"events":[{"event_id":"007dc4f561da86b9","registry":"ARIN","report_date":"2026-06-11","source":"transfers","raw_action":"TRANSFER","raw_line":null,"resource_type":"ipv4","resource":"157.194.0.0/16","start":"157.194.0.0","end":"157.194.255.255","classification":"MERGER_ACQUISITION","classification_label":"Merger/acquisition or reorganization","confidence":"CONFIRMED","source_rir":"ARIN","recipient_rir":"ARIN","source_organization":"HBO & Co.","recipient_organization":"UnitedHealth Group Incorporated","inventory_effect":"No effect on ARIN applicant inventory","inventory_effect_code":"NO_EFFECT","provisional":false,"classifier_version":"1.4.0","classified_at":"2026-10-14T00:19:28+00:00","page":"https://rirtracker.com/ip/157.194.0.0-157.194.255.255/#e-007dc4f561da86b9","report_page":"https://rirtracker.com/arin/reports/2026-06-11/","evidence_url":"https://rirtracker.com/api/v1/resources/ip/157.194.0.0-157.194.255.255.json","observed":"Merger/acquisition: HBO & Co. (ARIN) to UnitedHealth Group Incorporated (ARIN)","explanation":"ARIN's transfer log records a merger, acquisition or reorganization from HBO & Co. (ARIN) to UnitedHealth Group Incorporated (ARIN) on 2026-06-11 13:18 UTC. The registration changed hands; it is not a new allocation from ARIN. ARIN-Issued and ARIN's statistics don't show this change; only the transfer log records it.","evidence":[{"type":"transfer","url":"https://ftp.arin.net/pub/stats/arin/transfers/transfers_latest.json","retrieved_at":"2026-10-13T13:57:20+00:00","summary":"Transfer log: MERGER_ACQUISITION on 2026-06-11 13:18 UTC, HBO & Co. (ARIN) to UnitedHealth Group Incorporated (ARIN); resources moved: 157.194.0.0/16"},{"type":"delegated_before","url":"https://ftp.arin.net/pub/stats/arin/delegated-arin-extended-20260610","retrieved_at":"2026-10-09T19:02:38+00:00","summary":"ARIN delegated statistics 2026-06-10 (produced 2026-06-10T09:00:20+00:00), before the report: reserved"},{"type":"delegated_after","url":"https://ftp.arin.net/pub/stats/arin/delegated-arin-extended-20260612","retrieved_at":"2026-10-09T19:02:45+00:00","summary":"ARIN delegated statistics 2026-06-12 (produced 2026-06-12T09:00:21+00:00), after the report: allocated (dated 1992-01-24)"}]},{"event_id":"80497254f04c85c4","registry":"ARIN","report_date":"2025-07-28","source":"statistics","raw_action":"NOT_IN_ARIN_ISSUED","raw_line":null,"resource_type":"ipv4","resource":"157.194.0.0/16","start":"157.194.0.0","end":"157.194.255.255","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":"2026-10-14T00:13:30+00:00","page":"https://rirtracker.com/ip/157.194.0.0-157.194.255.255/#e-80497254f04c85c4","report_page":"https://rirtracker.com/arin/reports/2025-07-28/","evidence_url":"https://rirtracker.com/api/v1/resources/ip/157.194.0.0-157.194.255.255.json","observed":"157.194.0.0/16 allocated on 2025-07-28, reserved on 2025-07-29","hold":{"hold_rule_source_url":"https://www.arin.net/resources/guide/request/#reissuing-returned-revoked-and-reclaimed-resources","hold_rule_days":60,"estimated_hold_end":"2025-09-26","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 allocated (dated 1992-01-24) on 2025-07-27 and reserved on 2025-07-29. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed IPv4 space for 60 days before reissuing it, so the estimated hold end is 2025-09-26. This does not confirm availability.","evidence":[{"type":"statistics_diff","url":"https://ftp.arin.net/pub/stats/arin/archive/2025/delegated-arin-extended-20250729.gz","retrieved_at":"2026-10-13T00:04:09+00:00","summary":"Not listed in ARIN-Issued; found by comparing ARIN's daily statistics: 157.194.0.0/16 allocated on 2025-07-28, reserved on 2025-07-29"},{"type":"delegated_before","url":"https://ftp.arin.net/pub/stats/arin/archive/2025/delegated-arin-extended-20250727.gz","retrieved_at":"2026-10-13T00:04:04+00:00","summary":"ARIN delegated statistics 2025-07-27 (produced 2025-07-27T13:01:13+00:00), before the report: allocated (dated 1992-01-24)"},{"type":"delegated_after","url":"https://ftp.arin.net/pub/stats/arin/archive/2025/delegated-arin-extended-20250729.gz","retrieved_at":"2026-10-13T00:04:09+00:00","summary":"ARIN delegated statistics 2025-07-29 (produced 2025-07-29T13:01:13+00:00), after the report: reserved"}]}],"classification_history":{"007dc4f561da86b9":[{"raw_change_id":576380,"classification_code":"MERGER_ACQUISITION","confidence":"CONFIRMED","classifier_version":"1.4.0","classified_at":"2026-10-14T00:19:28+00:00","current":1,"public_explanation":"ARIN's transfer log records a merger, acquisition or reorganization from HBO & Co. (ARIN) to UnitedHealth Group Incorporated (ARIN) on 2026-06-11 13:18 UTC. The registration changed hands; it is not a new allocation from ARIN. ARIN-Issued and ARIN's statistics don't show this change; only the transfer log records it."}],"80497254f04c85c4":[{"raw_change_id":483441,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.3.0","classified_at":"2026-10-13T06:16:40+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 allocated (dated 1992-01-24) on 2025-07-27 and reserved on 2025-07-29. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed IPv4 space for 60 days before reissuing it, so the earliest estimated hold expiration is 2025-09-26. This does not confirm availability."},{"raw_change_id":483441,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.3.1","classified_at":"2026-10-13T08:23:55+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 allocated (dated 1992-01-24) on 2025-07-27 and reserved on 2025-07-29. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed IPv4 space for 60 days before reissuing it, so the earliest estimated hold expiration is 2025-09-26. This does not confirm availability."},{"raw_change_id":483441,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.3.2","classified_at":"2026-10-13T15:08:04+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 allocated (dated 1992-01-24) on 2025-07-27 and reserved on 2025-07-29. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed IPv4 space for 60 days before reissuing it, so the earliest estimated hold expiration is 2025-09-26. This does not confirm availability."},{"raw_change_id":483441,"classification_code":"REMOVED_REASON_UNKNOWN","confidence":"STRONG_INFERENCE","classifier_version":"1.4.0","classified_at":"2026-10-14T00:13:30+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 allocated (dated 1992-01-24) on 2025-07-27 and reserved on 2025-07-29. Public sources do not distinguish a voluntary return, revocation, or reclamation. ARIN holds returned, revoked and reclaimed IPv4 space for 60 days before reissuing it, so the estimated hold end is 2025-09-26. This does not confirm availability."}]},"arin_statistics_now":{"status":"allocated (dated 1992-01-24)"}}