Resideo has its own IEEE registrant — this resolves the Batch 006 consolidation question. Registered as "Resideo," it holds about 5 blocks (MA-L plus a CID), including 00:D0:2D (a legacy Honeywell Security block now attributed to Resideo), 48:A2:E6, 5C:FC:E1, and B8:2C:A0. The registered address is 2 Corporate Center Dr., Melville, NY — the legacy Honeywell residential-security address, not Resideo's current corporate HQ in Scottsdale, AZ. These OUIs appear on smart thermostats, security panels, water/leak and air sensors, and smoke/CO alarms. The corporate history is the key normalization fact: Honeywell completed the Resideo spin-off effective 29 October 2018 (the former Homes and ADI Global Distribution business; REZI began NYSE trading that day), and Resideo makes the Honeywell Home–branded thermostats under license — so the OUI says "Resideo" while the brand on the box says "Honeywell Home." Resideo also owns ADI Global Distribution and acquired First Alert/BRK Brands in 2022. For triage, a Resideo OUI almost certainly indicates a residential-class thermostat, alarm panel, or environmental sensor — an IoT/building-controls asset; on a corporate network it's a shadow-IT / unmanaged-building-device signal worth segmenting onto an IoT VLAN.
- IEEE assignment
- ~5 prefixes → "Resideo" (incl. legacy Honeywell Security block 00:D0:2D), registered Melville, NY, US [Confirmed] — IEEE MA-L
- Registry / block size
- MA-L plus a CID block; ~5 blocks [Confirmed] — maclookup.app (IEEE-sourced)
- HQ / country
- registrant 2 Corporate Center Dr., Melville, NY 11747, US (legacy Honeywell residential-security address); corporate HQ Scottsdale, AZ, US [Confirmed] — maclookup.app
- Company status
- active; Honeywell completed the Resideo spin-off eff. 2018-10-29 (former Homes + ADI Global Distribution business; REZI on NYSE); owns ADI Global, acquired First Alert/BRK (2022) [Confirmed] — honeywell.com
- Device types
- smart thermostats, security panels, water/leak and air sensors, smoke/CO alarms [Confirmed] — maclookup.app
- Notable products
- Honeywell Home T-series thermostats and the round thermostat (under license), Honeywell Home ProSeries security panels, First Alert alarms
- Verified prefix sample
- 00:D0:2D (legacy Honeywell Security), 48:A2:E6, 5C:FC:E1, B8:2C:A0 [Confirmed] — maclookup.app
- Special note
- 00:D0:2D predates the spinoff (legacy Honeywell/legacy block now attributed to Resideo) — a registrant-name-change flag. Honeywell Home–branded thermostats are made by Resideo under license (OUI says "Resideo," box says "Honeywell Home"). The IEEE registry publishes no assignment dates, so none is stated here. [Confirmed]
- Related vendors
- Honeywell (former parent, licensor of the Honeywell Home brand); ADI Global; First Alert/BRK (subsidiary)
- Analyst note
- A Resideo OUI almost certainly = a residential-class thermostat, alarm panel, or environmental sensor; on a corporate network, a shadow-IT / unmanaged-building-device signal worth segmenting onto an IoT VLAN.