MCOT INC. — 3 prefixes (MA-L)

MCOT INC. holds three IEEE MA-L blocks — 84:D5:A0, A4:56:1B, and F8:E4:4E — all registered to the same street address in Matsuyama, Ehime, Japan (Yogohigashi 1-5-12, 790-0044). One third-party aggregator renders the A4:56:1B block under the name "MCOT Corporation" rather than "MCOT INC.," but the identical registrant address across all three blocks indicates a single entity with an aggregator naming inconsistency rather than two separate companies. Searching that exact registrant address surfaces m-cot Co., Ltd. (株式会社エム・コット), a Japanese contract electronics engineering house at mcot.co.jp whose published company address (愛媛県松山市余戸東1-5-12) matches the OUI registrant address exactly. Its business is circuit design, PCB artwork design, prototype build and evaluation, and embedded firmware/software development — a B2B OEM design shop rather than a retail device brand. That model plausibly explains why the firm holds three separate OUI blocks: hardware it designs is branded and sold by its clients. No public device teardowns, packet captures, or product spec sheets reference these three specific prefixes in the wild, so device-type corroboration is Unknown rather than fabricated. The consolidation criterion is met on two independent grounds: multiple IEEE assignments and an identifiable operating company whose address matches the registry.

IEEE assignment

3 prefixes → MCOT INC. (MA-L) [Confirmed] — the IEEE MA-L registry (cached IEEE MA-L export); maclookup.app for 84:D5:A0, A4:56:1B, F8:E4:4E

Registry / block size

MA-L (24-bit OUI); 3 blocks. No matches in the IEEE MA-M registry (MA-M) or the IEEE MA-S registry (MA-S) [Confirmed] — the IEEE MA-L registry, the IEEE MA-M registry, the IEEE MA-S registry. NOTE: IEEE's public OUI data publishes NO assignment/registration date; any "date registered" or aggregator "updated" timestamp (e.g. maclookup.app's 2023-12-18 / 2017-12-28 / 2015-11-17) is a third-party database artifact, not an IEEE fact, and is not recorded as a registration date.

Registered name

MCOT INC. (A4:56:1B rendered "MCOT Corporation" by one aggregator — same address, treated as a naming inconsistency, not a distinct entity) [Confirmed] — maclookup.app (84D5A0, F8E44E, A4561B)

HQ / country

Yogohigashi 1-5-12, Matsuyama, Ehime 790-0044, Japan — identical across all three OUI blocks [Confirmed] — the IEEE MA-L registry; maclookup.app (84D5A0)

Identified operating company

m-cot Co., Ltd. (株式会社エム・コット), Matsuyama, Ehime — registrant-address match to mcot.co.jp's published company address is the corroborating link (not a direct self-identification tying the company to the OUI registry) [Likely] — https://www.mcot.co.jp/, https://www.mcot.co.jp/company.html

Business / industry

contract/OEM electronics engineering — circuit design, PCB artwork design, prototype build & evaluation, embedded firmware/software development [Likely] — https://www.mcot.co.jp/company.html

Company status

active (company site live) [Likely] — https://www.mcot.co.jp/

Device types

Unknown — no public teardowns, captures, product sheets, or forum threads reference 84:D5:A0, A4:56:1B, or F8:E4:4E; consistent with a B2B design house whose output is client-branded [Unknown] — no source found

Verified prefixes (all MA-L, MCOT INC.)

84:D5:A0, A4:56:1B, F8:E4:4E [Confirmed] — the IEEE MA-L registry; maclookup.app

Security context

Unknown — no CVEs, advisories, or device-specific security writeups tied to the entity or these prefixes; end-devices would be client-branded, so posture attaches to the end product [Unknown] — no source found

Analyst note

A globally-administered MCOT OUI on a device indicates hardware designed/registered by this contract-design firm; because the firm's output is typically branded by its clients, the OUI identifies the design origin rather than a retail product line.