This join of registry records associates the United States Department of Defense (DoD) name with 300,150,784 IPv4 addresses and 1,008 ASN records, or 10.82% of attributed IPv4 addresses. The large total reflects early internet allocations, before modern commercial registry quotas were established.
Top largest IP address holders and network owners
The largest IP address holders are ranked by joining allocated or assigned IPv4 ranges to ASN rows through opaque IDs in RIR delegated files. Names are not independently verified legal entities or parent companies. The top ten account for over 28% of attributed IPv4 address space; the table ranks them by attributed holdings.
| # | Organization Name | Country | Registry | IPv4 Addresses | Attributed Share |
|---|---|---|---|---|---|
| 1 | United States Department of Defense (DoD) | US | ARIN | 300,150,784 | 10.82% |
| 2 | AT&T Enterprises, LLC | US | ARIN | 107,344,896 | 3.87% |
| 3 | Verizon Business | US | ARIN | 103,814,656 | 3.74% |
| 4 | Amazon.com, Inc. | US | ARIN | 102,085,376 | 3.68% |
| 5 | Comcast Cable Communications, LLC | US | ARIN | 70,055,424 | 2.53% |
| 6 | Microsoft Corporation | US | ARIN | 45,692,416 | 1.65% |
| 7 | China Telecom | CN | APNIC | 44,151,040 | 1.59% |
| 8 | Microsoft Limited | GB | RIPE NCC | 38,073,088 | 1.37% |
| 9 | Cogent Communications, LLC | US | ARIN | 37,615,872 | 1.36% |
| 10 | Charter Communications Inc | US | ARIN | 37,005,056 | 1.33% |
| Total | 58,606 Holders Total | Global | All RIRs | 2,773,060,192 | 100.00% |
Military, telecom, and hyperscale cloud holders
The largest corporate and institutional IPv4 holdings fall into three groups: legacy military blocks, national telecommunications operators, and hyperscale cloud providers.
The US Department of Defense holds multiple unrouted and active /8 networks assigned in the early 1980s, including historical blocks such as 6.0.0.0/8, 11.0.0.0/8, and 22.0.0.0/8. Major telecommunications operators such as AT&T Enterprises (107,344,896 addresses), Verizon Business (103,814,656 addresses), Comcast Cable (70,055,424 addresses), and China Telecom (44,151,040 addresses) hold large address blocks for residential broadband and enterprise mobile subscribers.
Cloud infrastructure providers have acquired IPv4 space on the secondary transfer market for public IP addresses used by virtual machines and load balancers. Amazon.com controls 102,085,376 IPv4 addresses, while Microsoft Corporation holds 45,692,416 addresses under its US ARIN entity and an additional 38,073,088 addresses under Microsoft Limited in RIPE NCC. Combined, Microsoft's global entities hold over 83.7 million IPv4 addresses.
Corporate consolidation and secondary market acquisitions
Corporate mergers and secondary market acquisitions have brought previously separate IPv4 registries under unified parent entities.
Hyperscale cloud operators such as Amazon AWS, Microsoft Azure, and Google Cloud have purchased millions of IPv4 addresses from legacy holders for enterprise cloud migration. Cloud virtual machines require elastic public IP assignments, so providers maintain substantial IPv4 inventories.
Holder profiles and global network footprints
Major holders use IPv4 allocations for different parts of internet operations. AT&T, Verizon, Comcast, and Charter use most of their addresses for dynamic subscriber pools, business leased lines, and voice-over-IP (VoIP) routing across North America.
Tier-1 transit providers like Cogent Communications (37,615,872 addresses across 92 ASNs) manage global backbone infrastructure that interconnects regional ISPs. In Asia, state-owned telecom giants like China Telecom manage 44,151,040 addresses across 489 ASNs, routing backbone traffic for hundreds of millions of home broadband connections.
Amazon and Microsoft use their address holdings across global cloud availability zones. Dedicated IPv4 holdings let cloud hosters offer static addresses to enterprise customers running web applications, databases, and API gateways.
Impact of IP holding concentration on global routing security
Concentration of address space in major organizational entities influences Border Gateway Protocol (BGP) security and Resource Public Key Infrastructure (RPKI) deployment. When large holders publish Route Origin Authorizations (ROAs), cryptographically validating their BGP announcements prevents route hijacking and misconfiguration outages.
Major cloud providers and Tier-1 carriers enforce strict RPKI origin validation across their ASNs. For enterprise networks peering with large address holders, validating RPKI signatures ensures that traffic destined for legitimate IPv4 blocks cannot be intercepted by unauthorized intermediate networks.
Autonomous system architecture and multi-homing
Large network holders route their address blocks using Border Gateway Protocol (BGP) across Autonomous Systems. Multi-homed organizations announce the same IP prefixes across multiple Tier-1 transit providers to guarantee redundant path connectivity and automatic failover in the event of fiber cuts or routing outages.
When an organization holds hundreds of millions of IPv4 addresses, efficient BGP route aggregation is essential to prevent global routing table instability. Holders structure their allocated CIDR blocks into summary prefixes (such as /16 or /20 subnets) before announcing them to international peer networks.
How we measured internet address space ownership
Our findings are compiled from daily RIR delegated statistics files published by the five Regional Internet Registries: ARIN, RIPE NCC, APNIC, LACNIC, and AFRINIC. The measured date for this analysis is October 10, 2026.
Our measurement methodology consolidates organizational records by matching parent entity names, legal corporate registries, and associated Autonomous System Numbers. Across 3,687,597,216 allocated IPv4 addresses, this join associates 2,773,060,192 addresses with 58,606 holder names. The remaining 914,537,024 are allocated addresses whose holder could not be resolved by this join because no corresponding ASN row or usable ASN description was found. This method does not verify parent companies or legal records.
Large address holders must maintain accurate WHOIS registration contacts and reverse DNS records. For multinational cloud and telecom operators, outdated WHOIS records across sub-allocated CIDR blocks can lead to routing anomalies, delayed security incident response, and inaccurate IP geolocation for end users.
Inspecting network owners and next steps
When you query a public IP address, knowing its underlying holder clarifies whether the connection originates from a residential ISP, a corporate network, or a cloud hosting platform. To locate the specific owner, ISP, and ASN for any IP address, check our free IP lookup tool. To determine whether an IP belongs to a commercial hosting holder or proxy service, use our proxy and VPN check tool. For related guides on IP address structures and blacklist reputation, read our articles on public vs private IP addresses and how to check if an IP is blacklisted.