Alarm.com — 3 prefixes (MA-L)

A MAC address beginning 00:1C:FA, 50:40:74, or B8:3A:9D belongs to Alarm.com, the publicly traded (NASDAQ: ALRM) cloud-connected smart-home and security platform provider — these are the vendor's three confirmed IEEE MA-L (48-bit) OUI assignments, with no MA-M or MA-S blocks found under the same name.

The three prefixes cluster at two Virginia addresses roughly five miles apart: 00:1C:FA registers to 8150 Leesburg Pike, Vienna, VA 22182, while 50:40:74 and B8:3A:9D both register to 8281 Greensboro Dr., Suite 100, Tysons, VA 22102. Two independent third-party vendor lookups (maclookup.app, hwaddress.com) agree on all three prefixes under the same registrant.

Business-registration records list the registrant as "Alarm.Com Incorporated" (Alarm.com Holdings, Inc.), a cloud-based smart-home and commercial security IoT platform sold through professional security dealers — consistent with, though not directly confirming, a hardware program spanning multiple device generations.

The company's described product line covers security panels and touchscreen hubs, door locks, motion sensors, garage-door controllers, cameras and video doorbells, smart thermostats, and energy/water sensors. No source in this pass ties any one of the three specific prefixes to a named model number, so device-to-prefix mapping stays Unknown.

Third-party aggregators list "registered" dates of 2007, 2015, and 2023 for the three prefixes, but these are database-scrape artifacts, not IEEE facts — the IEEE OUI registry publishes no assignment dates. No vendor-specific security incident or CVE was found for these OUIs in this pass.

IEEE assignment

3 MA-L prefixes (00:1C:FA, 50:40:74, B8:3A:9D) → Alarm.com [Confirmed] — the IEEE MA-L registry (lines 26052, 31877, 27008)

Registry / block size

MA-L (24-bit OUI) x3; no MA-M assignments in the IEEE MA-M registry, no Alarm.com MA-S assignments in the IEEE MA-S registry [Confirmed] — the cached registry snapshots{the IEEE MA-L registry, the IEEE MA-M registry, the IEEE MA-S registry}

HQ / addresses

8150 Leesburg Pike, Vienna, VA 22182 (00:1C:FA); 8281 Greensboro Dr., Suite 100, Tysons, VA 22102 (50:40:74, B8:3A:9D) [Confirmed] — IEEE MA-L

Company status

active, publicly traded, NASDAQ: ALRM [Likely] — nasdaq.com/market-activity/stocks/alrm, en.wikipedia.org/wiki/Alarm.com

Device types

security panels/hubs, door locks, motion sensors, garage-door controllers, cameras/video doorbells, thermostats, energy/water sensors [Likely] — en.wikipedia.org/wiki/Alarm.com

Registrant corporate name

Alarm.Com Incorporated / Alarm.com Holdings, Inc. [Likely] — opengovus.com/washington-corporation/604152428, opengovco.com/business/20141207182

Registration-date caveat

third-party "registered" dates (2007/2015/2023) are aggregator database artifacts, not IEEE facts — IEEE's the IEEE MA-L registry publishes no assignment dates [Confirmed] — maclookup.app/vendors/alarm-com, hwaddress.com/company/alarmcom

OUI-to-model mapping

Unknown — no source found linking a specific prefix to a named hardware model [Unknown]

Security/abuse context

Unknown — no vendor-specific CVE or incident research found this pass [Unknown]

Direct IEEE standards-oui.ieee.org confirmation

not obtained this session (HTTP 418 on fetch attempt); corroborated instead via cached registry CSV plus two independent third-party aggregators [Confirmed via registry CSV; Likely via web cross-check] — the IEEE MA-L registry, maclookup.app, hwaddress.com