Silicon Laboratories — 144 prefixes (MA-L); Zigbee/Thread/BLE/Z-Wave silicon, OUI ≠ device brand

Silicon Laboratories holds 144 MA-L blocks in the cached IEEE registry, all registered to "Silicon Laboratories" at 400 West Cesar Chavez Street, Austin, TX 78701 (older blocks carry a 7000 W. William Cannon Dr., Austin TX 78735 address). Verified samples from the registry include 38:5C:FB, F4:B3:B1, DC:8E:95, 84:B4:DB, and CC:CC:CC. These OUIs land on Silicon Labs wireless silicon — the EFR32 Wireless Gecko SoC family and the BGM/MGM/ZGM/FGM wireless modules — which embed Zigbee, Thread, Matter, Bluetooth LE/mesh, Z-Wave, Wi-SUN, and Wi-Fi 6, often concurrently on a single multiprotocol part. The slug vendor-silicon-laboratories resolves to the same entity as the existing vendor-silicon-labs entry: same organization, same registry footprint. The key analyst point is the chipset pattern — a Silicon Labs OUI identifies a device built on Silicon Labs silicon regardless of the brand printed on the case. On a monitored network such a MAC almost always belongs to a low-power IoT or smart-home endpoint (Zigbee coordinator/router/end-device, Z-Wave node, BLE sensor, Thread/Matter device), not a general-purpose computer; unexpected autonomous outbound traffic from one warrants a look. Two security caveats are worth carrying: older Z-Wave chipsets (100–500 series) carry documented protocol-layer weaknesses (CERT/CC VU#142629), and a Texas Instruments acquisition of Silicon Labs was announced in February 2026 and was still pending as of June 2026, so the brand and these OUI registrations may change post-close.

IEEE assignment

144 prefixes → "Silicon Laboratories", registered Austin, TX, US [Confirmed] — cached IEEE MA-L registry (144 lines)

Registry / block size

MA-L (24-bit OUI); 144 blocks in the cached registry. No MA-M (the IEEE MA-M registry) and no MA-S (the IEEE MA-S registry) matches. [Confirmed] — the IEEE MA-L registry (144), the IEEE MA-M registry (0), the IEEE MA-S registry (0). NOTE: a third-party vendor profile (Netify) reports ~146 prefixes; the count is a moving third-party snapshot and drifts — the 144 here is the cached first-party registry line count.

HQ / country

400 West Cesar Chavez Street, Austin TX 78701, US (registry; variants in-CSV: "400 West Cesar Chavez", "400 W. Cesar Chavez St."). Older blocks: 7000 W. William Cannon Dr., Austin TX 78735. [Confirmed] — the IEEE MA-L registry

Company status

active; acquired Zigbee pioneer Ember [Confirmed] — silabs.com. Pending acquisition: Texas Instruments announced a definitive agreement to acquire Silicon Labs (~$7.5B, $231/share all-cash) on 2026-02-04; pending as of 2026-06 [Confirmed] — ti.com news release (2026-02-04)

Device types

Zigbee/Thread/Matter/BLE/Z-Wave SoCs (EFR32 Wireless Gecko), wireless modules (BGM/MGM/ZGM/FGM), mixed-signal ICs, microcontrollers [Confirmed] — silabs.com/wireless, netify.ai

Notable products

EFR32 Wireless Gecko SoCs; BGM/MGM/ZGM/FGM wireless modules

Verified prefix sample (all MA-L, "Silicon Laboratories")

38:5C:FB, F4:B3:B1, DC:8E:95, 84:B4:DB, CC:CC:CC [Confirmed] — the IEEE MA-L registry (lines 557, 596, 639, 726, and the full 144-line set)

Security note

Older Z-Wave chipsets (100/200/300/500-series) carry documented protocol-layer weaknesses — lack of encryption/replay protection, DoS/battery-exhaustion (CVE-2020-9057..9061, CVE-2020-10137; downstream devices from Aeotec, Fibaro, Schlage, Samsung affected) [Confirmed] — CERT/CC VU#142629 (kb.cert.org). On the defensive side, Series 2 Secure Vault reached PSA Certified Level 3 and the Series 3 SiXG301 was announced (Aug 2025) as the first PSA Level 4 SoC

[Confirmed] — silabs.com/security, news.silabs.com (2025-08-04)

Special note

A Silicon Labs OUI is a chipset-OUI flag — EFR32 is ubiquitous in Zigbee/Thread/Matter and the company is foundational in Zigbee smart-home devices (acquired Ember). The IEEE registry publishes no assignment dates, so none is stated here; any "date registered" on third-party MAC tools is a database scrape artifact, not an IEEE fact. [Confirmed]

Related vendors

Ember (acquired); Texas Instruments (pending acquirer, announced 2026-02-04)

Analyst note

A Silicon Labs OUI typically indicates a Zigbee/Thread/Matter/Z-Wave smart-home or IoT endpoint built on Silabs silicon — brand determined elsewhere. Z-Wave devices on older chipsets may lack encryption; firmware/protocol audits advised in high-security environments.