Aehr Test Systems — 00:20:BF (MA-L)

The OUI prefix 00:20:BF is registered to "AEHR TEST SYSTEMS" at 1667 Plymouth Street, Mountain View, CA 94043, US — a single MA-L block, the company's only assignment across the IEEE MA-L, MA-M, and MA-S registries. Behind that one registration is a substantive, long-established company: Aehr Test Systems (NASDAQ: AEHR), founded in 1977 and now headquartered in Fremont, CA, builds wafer-level burn-in and semiconductor test equipment. The registry's Mountain View address is a historical location consistent with a late-1990s registration, predating the current Fremont HQ. The MAC block most plausibly identifies the Ethernet hardware in Aehr's ATX- and MAX-series test systems: distributor listings independently reference an "ATX/MAX Auxiliary Network Interface Module" and an "ATX Network Interface ISA Module" sold as accessories for those systems, though a direct fetch of those listings was blocked, so the exact tie between this OUI and that hardware is inferred rather than confirmed. No IEEE assignment date exists — IEEE publishes none — and any "registered" date shown by third-party lookup aggregators is a database-scrape artifact, not an IEEE fact. No security advisories, CVEs, or abuse reports reference Aehr devices as a networked-hardware source. Encountering this OUI on a network most likely indicates industrial semiconductor-test equipment rather than a consumer or general-purpose device.

IEEE assignment

00:20:BF → AEHR TEST SYSTEMS, MA-L block [Confirmed] — the IEEE MA-L registry line 37876; https://maclookup.app/macaddress/0020BF

Registry / block size

MA-L (24-bit OUI) [Confirmed] — the IEEE MA-L registry line 37876

Registered address

1667 Plymouth Street, Mountain View, CA 94043, US (historical registry address; current corporate HQ is Fremont, CA) [Confirmed] — the IEEE MA-L registry line 37876; https://maclookup.app/macaddress/0020BF

Country

US [Confirmed] — the IEEE MA-L registry line 37876

Company status

active; Aehr Test Systems, Inc., NASDAQ: AEHR, founded 1977, HQ Fremont, CA [Confirmed] — https://www.aehr.com/about-us/; https://www.aehr.com/

Industry

semiconductor wafer-level burn-in and test equipment [Confirmed] — https://www.aehr.com/; https://www.semi.org/en/resources/member-directory/aehr-test-systems

Device types

ATX- and MAX-series semiconductor wafer test systems; associated ATX/MAX network-interface modules [Likely] — distributor listings referenced (ArtisanTG, part 93161-1 and 130-15724-01); direct page fetch blocked (HTTP 403), so tie of this exact OUI to that hardware is inferred — https://www.artisantg.com/TestMeasurement/93161-1/AEHR-Test-Systems-ATX-MAX-Auxillary-Network-Interface-Module

Additional blocks

none — single MA-L block; no MA-M (the IEEE MA-M registry) or MA-S (the IEEE MA-S registry) registration under this org name [Confirmed] — the IEEE MA-L registry, the IEEE MA-M registry, the IEEE MA-S registry (searched)

Registration date

Unknown — IEEE publishes no assignment/registration date for OUIs; a third-party aggregator (maclookup.app) shows "22 April 1998" but that is a database-scrape artifact, not an IEEE fact, and must not be recorded as an IEEE date

[Confirmed — no IEEE date exists] — https://maclookup.app/macaddress/0020BF

Security context

no CVEs, advisories, breach reports, or abuse discussion found referencing Aehr devices as a networked source [Unknown — sourced null]

Analyst note

this OUI most likely identifies industrial semiconductor-test equipment (ATX/MAX-series systems); it is a single-block registrant but backed by a real, publicly traded company with product context, not a bare shell.