Cofractal, Inc. holds the MA-L OUI block E4:DC:5F, registered in the IEEE oui.csv registry to a Sunnyvale, California mailbox address (209 E Java Dr. #61593, Sunnyvale, CA 94089, US). Unlike consumer-electronics OUI holders, Cofractal is not a recognized hardware brand: its primary public identity is as an independent US network operator and ISP running AS26073, with global peering across North American and European internet exchanges, an open peering policy, and upstream transit via Cogent Communications and Hurricane Electric. IPinfo classifies the ASN as "ISP, Business or Hosting," and the company also fronts a cloud platform at cloud.cofractal.com behind a login wall. Because the OUI is an MA-L (24-bit, ~16 million addresses) and no public product catalog or hardware datasheet is reachable — cofractal.com returned an HTTP 523 Cloudflare error during research — the most defensible reading is that E4:DC:5F addresses belong to Cofractal's own infrastructure (routers, network appliances, virtual-machine NICs) rather than to any retail device line. The specific device category cannot be confirmed from public sources and is left Unknown rather than guessed. IEEE publishes no allocation date for OUI registrations, so any "date registered" figure surfaced by third-party MAC-lookup databases is a database artifact, not an authoritative registration date.
- IEEE assignment
- E4:DC:5F → Cofractal, Inc. [Confirmed] — IEEE oui.csv (MA-L), row 934; maclookup.app/vendors/cofractal-inc
- Registry / block size
- MA-L (24-bit OUI; ~16M addresses) [Confirmed] — IEEE oui.csv. Not present in mam.csv (MA-M) or oui36.csv (MA-S) — single MA-L block only.
- Registered address / country
- 209 E Java Dr. #61593, Sunnyvale, CA 94089, US (registry mailbox address) [Confirmed] — IEEE oui.csv (MA-L)
- Company status
- active independent network operator / ISP; runs AS26073 [Confirmed] — ipinfo.io/AS26073, peeringdb.com/asn/26073, bgp.he.net/AS26073
- Company description
- US-based ISP / transit network and cloud-services provider; ~4,864 IPv4 addresses on AS26073, global peering (NA + EU IXPs), open peering policy, upstreams Cogent + Hurricane Electric; IPinfo class "ISP, Business or Hosting" [Confirmed] — ipinfo.io/AS26073, peeringdb.com/asn/26073, bgp.he.net/AS26073
- Device types
- Unknown — no public evidence of manufactured end-user hardware. MA-L block is consistent with internal infrastructure (routers, network appliances, virtual NICs) operated within Cofractal's own network, but no product catalog/datasheet is publicly reachable (cofractal.com HTTP 523; cloud.cofractal.com login-walled) [Unknown] — maclookup.app/vendors/cofractal-inc, bgp.he.net/AS26073, peeringdb.com/asn/26073
- Registration date
- none published by IEEE. Third-party MAC databases cite "2021-04-20," but that is a database artifact, not an IEEE fact — treat as approximate only [Likely (artifact, not authoritative)] — maclookup.app/vendors/cofractal-inc
- No-IEEE-date note
- IEEE public OUI data (oui.csv columns: Registry, Assignment, Organization Name, Organization Address) contains NO assignment/registration date. Any "date registered" from a lookup tool is a third-party database artifact. [Confirmed] — standards-oui.ieee.org/oui/oui.csv
- Related identifier
- ASN 26073 (Cofractal's autonomous system) [Confirmed] — bgp.he.net/AS26073, peeringdb.com/asn/26073
- Analyst / security note
- Low public footprint. E4:DC:5F MACs most plausibly identify Cofractal's own internal network infrastructure rather than consumer devices. No known CVEs, abuse reports, or security advisories tied to Cofractal hardware. IPinfo notes VPN traffic on AS26073, an expected signal for a hosting/transit ASN, not an indicator of malicious use. [Likely] — ipinfo.io/AS26073, bgp.he.net/AS26073