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AS19858
GENSLER - M. Arthur Gensler Jr. & Associates, Inc. Announcing routesAS nameGENSLER
OrganisationM. Arthur Gensler Jr. & Associates, Inc.
Registry (RIR)ARIN
HandleAS19858
RangeAS19858
Registered21 Feb 2001
Last changed01 Jul 2025
2IPv4 prefixes
0IPv6 prefixes
3Upstreams
0Downstreams
Upstreams
| AS | Network name | Visibility |
|---|---|---|
| AS174 | COGENT-174 - Cogent Communications, LLC | 262 |
| AS6994 | FASTMETRICS - Fastmetrics | 25 |
| AS7018 | ATT-INTERNET4 - AT&T Enterprises, LLC | 3 |
Downstreams
None seen.
IPv4 prefixes (2)
RPKI-validate all prefixes of AS19858
Contacts
| Role | Name | Handle | Email / phone | Address |
|---|---|---|---|---|
| registrant | M. Arthur Gensler Jr. & Associates, Inc. | GAA | 2101 Webster St. , Suite 2000, Oakland, CA, 94612, United States | |
| noc, technical, administrative, abuse, routing | Matthew Baltera | BALTE2-ARIN | [email protected], +1-832-496-8696 | 1011 South Congress Avenue, Bldg. 1, Suite 200, Austin, TX, 78704, United States |
| abuse, routing, technical, noc | Nathan Daniel Eigsti | NDE44-ARIN | [email protected], +1-510-625-7449 | 2101 Webster St., Suite 2000, Oakland, CA, 94612, United States |
| technical | LORI HEROLD | HEROL-ARIN | [email protected], +1-415-836-4265 | 1033 JEFFERSON ST NW, BLDG MAIN FLR 1 SUIT 103, ATLANTA, GA, 30318, United States |
| technical | Lauren Ashley Bedrick | LAB21-ARIN | [email protected], +1-702-560-5616 | 848 N. Rainbow Blvd #5212, Las Vegas, NV, 89107, United States |
| technical | MAUREEN RANEY | RANEY3-ARIN | [email protected], +1-303-893-7129 | 4675 MACARTHUR CT, SUIT 100, NEWPORT BEACH, CA, 92660, United States |
| abuse, technical | Matthew Baltera | BALTE2-ARIN | [email protected], +1-832-496-8696 | 1011 South Congress Avenue, Bldg. 1, Suite 200, Austin, TX, 78704, United States |
Raw registry response
{
"endAutnum": 19858,
"entities": [
{
"entities": [
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-04-17T10:23:36-04:00"
},
{
"eventAction": "registration",
"eventDate": "2025-04-17T13:35:20-04:00"
}
],
"handle": "BALTE2-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/BALTE2-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/poc/BALTE2-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"noc",
"technical",
"administrative",
"abuse",
"routing"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1011 South Congress Avenue\nBldg. 1, Suite 200\nAustin\nTX\n78704\nUnited States"
},
"text",
[
"",
"",
"",
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"",
""
]
],
[
"fn",
[],
"text",
"Matthew Baltera"
],
[
"n",
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"text",
[
"Baltera",
"Matthew",
"",
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""
]
],
[
"kind",
[],
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],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-832-496-8696"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-06-01T09:44:07-04:00"
},
{
"eventAction": "registration",
"eventDate": "2025-06-30T18:16:08-04:00"
}
],
"handle": "NDE44-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/NDE44-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/poc/NDE44-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"abuse",
"routing",
"technical",
"noc"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "2101 Webster St.\nSuite 2000\nOakland\nCA\n94612\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Nathan Daniel Eigsti"
],
[
"n",
[],
"text",
[
"Eigsti",
"Nathan",
"Daniel",
"",
""
]
],
[
"kind",
[],
"text",
"individual"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-510-625-7449"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2022-04-12T20:24:12-04:00"
},
{
"eventAction": "registration",
"eventDate": "2014-11-06T12:03:03-05:00"
}
],
"handle": "HEROL-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/HEROL-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/poc/HEROL-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"ARIN has attempted to validate the data for this POC, but has received no response from the POC since 2023-04-12"
],
"title": "Unvalidated POC"
}
],
"roles": [
"technical"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1033 JEFFERSON ST NW\nBLDG MAIN FLR 1 SUIT 103\nATLANTA\nGA\n30318\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"LORI HEROLD"
],
[
"n",
[],
"text",
[
"HEROLD",
"LORI",
"",
"",
""
]
],
[
"kind",
[],
"text",
"individual"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-415-836-4265"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-09-09T09:25:35-04:00"
},
{
"eventAction": "registration",
"eventDate": "2023-09-08T17:51:58-04:00"
}
],
"handle": "LAB21-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/LAB21-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/poc/LAB21-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"technical"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "848 N. Rainbow Blvd #5212\nLas Vegas\nNV\n89107\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Lauren Ashley Bedrick"
],
[
"n",
[],
"text",
[
"Bedrick",
"Lauren ",
"Ashley",
"",
""
]
],
[
"kind",
[],
"text",
"individual"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-702-560-5616"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2016-09-22T11:31:05-04:00"
},
{
"eventAction": "registration",
"eventDate": "2015-03-16T16:16:43-04:00"
}
],
"handle": "RANEY3-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/RANEY3-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/poc/RANEY3-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"remarks": [
{
"description": [
"ARIN has attempted to validate the data for this POC, but has received no response from the POC since 2022-04-13"
],
"title": "Unvalidated POC"
}
],
"roles": [
"technical"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "4675 MACARTHUR CT\nSUIT 100\nNEWPORT BEACH\nCA\n92660\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"MAUREEN RANEY"
],
[
"n",
[],
"text",
[
"RANEY",
"MAUREEN",
"",
"",
""
]
],
[
"kind",
[],
"text",
"individual"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-303-893-7129"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2025-06-30T18:17:31-04:00"
},
{
"eventAction": "registration",
"eventDate": "1990-05-29T00:00:00-04:00"
}
],
"handle": "GAA",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/GAA",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/org/GAA",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"registrant"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"fn",
[],
"text",
"M. Arthur Gensler Jr. & Associates, Inc."
],
[
"adr",
{
"label": "2101 Webster St.\r\nSuite 2000\nOakland\nCA\n94612\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"kind",
[],
"text",
"org"
]
]
]
},
{
"events": [
{
"eventAction": "last changed",
"eventDate": "2026-04-17T10:23:36-04:00"
},
{
"eventAction": "registration",
"eventDate": "2025-04-17T13:35:20-04:00"
}
],
"handle": "BALTE2-ARIN",
"links": [
{
"href": "https://rdap.arin.net/registry/entity/BALTE2-ARIN",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/poc/BALTE2-ARIN",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"objectClassName": "entity",
"port43": "whois.arin.net",
"roles": [
"abuse",
"technical"
],
"status": [
"validated"
],
"vcardArray": [
"vcard",
[
[
"version",
[],
"text",
"4.0"
],
[
"adr",
{
"label": "1011 South Congress Avenue\nBldg. 1, Suite 200\nAustin\nTX\n78704\nUnited States"
},
"text",
[
"",
"",
"",
"",
"",
"",
""
]
],
[
"fn",
[],
"text",
"Matthew Baltera"
],
[
"n",
[],
"text",
[
"Baltera",
"Matthew",
"",
"",
""
]
],
[
"kind",
[],
"text",
"individual"
],
[
"email",
[],
"text",
"[email protected]"
],
[
"tel",
{
"type": [
"work",
"voice"
]
},
"text",
"+1-832-496-8696"
]
]
]
}
],
"events": [
{
"eventAction": "last changed",
"eventDate": "2025-06-30T18:04:02-04:00"
},
{
"eventAction": "registration",
"eventDate": "2001-02-21T00:00:00-05:00"
}
],
"handle": "AS19858",
"links": [
{
"href": "https://rdap.arin.net/registry/autnum/19858",
"rel": "self",
"type": "application/rdap+json",
"value": "https://rdap.arin.net/registry/autnum/19858"
},
{
"href": "https://whois.arin.net/rest/asn/AS19858",
"rel": "alternate",
"type": "application/xml",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"name": "GENSLER",
"notices": [
{
"description": [
"By using the ARIN RDAP/Whois service, you are agreeing to the RDAP/Whois Terms of Use"
],
"links": [
{
"href": "https://www.arin.net/resources/registry/whois/tou/",
"rel": "terms-of-service",
"type": "text/html",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"title": "Terms of Service"
},
{
"description": [
"If you see inaccuracies in the results, please visit: "
],
"links": [
{
"href": "https://www.arin.net/resources/registry/whois/inaccuracy_reporting/",
"rel": "inaccuracy-report",
"type": "text/html",
"value": "https://rdap.arin.net/registry/autnum/19858"
}
],
"title": "Whois Inaccuracy Reporting"
},
{
"description": [
"Copyright 1997-2026, American Registry for Internet Numbers, Ltd."
],
"title": "Copyright Notice"
}
],
"objectClassName": "autnum",
"port43": "whois.arin.net",
"rdapConformance": [
"nro_rdap_profile_0",
"rdap_level_0",
"nro_rdap_profile_asn_flat_0"
],
"startAutnum": 19858,
"status": [
"active"
]
}Results come from public internet registries and live global routing data. Results are cached for up to an hour. Lookups are logged with your IP address to prevent abuse — see our Privacy Policy.