Every change the tracker has found, newest first. It covers ARIN from 2008-12-01, the RIPE NCC from 2010-04-23, APNIC from 2008-02-15, LACNIC from 2012-06-29 and AFRINIC from 2012-10-03.
2025-10-15ARIN+ AddApparent reissuance of previously removed resourceObserved only
ARIN-Issued
Add AS11531
Inventory
Likely issued from ARIN-controlled inventory
No transfer record matches. ARIN's statistics show it available on 2025-10-14 and assigned (dated 2025-10-15) on 2025-10-16. The tracker saw this range released from hold on 2025-10-14 (AS11531), so it appears to have been issued again from ARIN's pool. Another change to this range was reported the day before or after (2025-10-14: Remove AS11531), so the before-and-after statistics may include it.
Evidence (3) · classifier 1.4.0,
ARIN-IssuedARIN-Issued report for 2025-10-15: "Add AS11531"source · retrieved
BeforeARIN delegated statistics 2025-10-14 (produced 2025-10-14T13:00:47+00:00), before the report: availablesource · retrieved
AfterARIN delegated statistics 2025-10-16 (produced 2025-10-16T13:00:46+00:00), after the report: assigned (dated 2025-10-15)source · retrieved
Classification history for this change (4 versions)
: Apparent reissuance of previously removed resource, observed only (classifier 1.3.0)
: Apparent reissuance of previously removed resource, observed only (classifier 1.3.1)
: Apparent reissuance of previously removed resource, observed only (classifier 1.3.2)
: Apparent reissuance of previously removed resource, observed only (classifier 1.4.0) current
2025-10-14ARIN− RemoveReleased from hold (ARIN lists it as 'available')Observed only
ARIN-Issued
Remove AS11531
Inventory
ARIN's statistics now list it as 'available'; reissue not confirmed
ARIN's statistics show it reserved on 2025-10-13 and available on 2025-10-15. ARIN took it out of its reserved (held) records; its statistics now give it the status 'available'. The tracker saw it removed from registration on 2009-01-26, 6105 days earlier. That is ARIN's own label: whether and when it is reissued is not confirmed. Another change to this range was reported the day before or after (2025-10-15: Add AS11531), so the before-and-after statistics may include it.
Evidence (3) · classifier 1.4.0,
ARIN-IssuedARIN-Issued report for 2025-10-14: "Remove AS11531"source · retrieved
BeforeARIN delegated statistics 2025-10-13 (produced 2025-10-13T13:00:46+00:00), before the report: reservedsource · retrieved
AfterARIN delegated statistics 2025-10-15 (produced 2025-10-15T13:00:47+00:00), after the report: availablesource · retrieved
Classification history for this change (4 versions)
: Released from hold (ARIN lists it as 'available'), observed only (classifier 1.3.0)
: Released from hold (ARIN lists it as 'available'), observed only (classifier 1.3.1)
: Released from hold (ARIN lists it as 'available'), observed only (classifier 1.3.2)
: Released from hold (ARIN lists it as 'available'), observed only (classifier 1.4.0) current
2009-01-26ARINNot in ARIN-IssuedRemoved (return, revocation or reclamation not publicly distinguishable)Strong inference
Inventory
Possible future reissue candidate after hold
Hold estimate
Estimated hold end 2009-07-26. Possible reissue candidate after this date; not confirmed available.
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 1998-09-23) on 2009-01-25 and not issued on 2009-01-27. (Until 2013-03-05, ARIN's statistics list only what's issued.) 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 2009-07-26. This does not confirm availability.
Evidence (3) · classifier 1.4.0,
StatisticsNot listed in ARIN-Issued; found by comparing ARIN's daily statistics: AS11531 allocated on 2009-01-26, not listed on 2009-01-27source · retrieved
BeforeARIN delegated statistics 2009-01-25, before the report: allocated (dated 1998-09-23)source · retrieved
AfterARIN delegated statistics 2009-01-27, after the report: not issuedsource · retrieved
Classification history for this change (4 versions)
: Removed (return, revocation or reclamation not publicly distinguishable), strong inference (classifier 1.3.0)
: Removed (return, revocation or reclamation not publicly distinguishable), strong inference (classifier 1.3.1)
: Removed (return, revocation or reclamation not publicly distinguishable), strong inference (classifier 1.3.2)
: Removed (return, revocation or reclamation not publicly distinguishable), strong inference (classifier 1.4.0) current
Transfer records
No transfer log has a transfer of any part of this ASN.
RDAP lookups
Not looked up. The tracker queries RDAP for changes as they're reported (on first sight, after 24 hours and after seven days); older changes aren't looked up because today's RDAP says nothing about the past.