DBG (DBG Technology / Huizhou Guanghong) — 4 prefixes (MA-L + MA-M)

The "DBG" label consolidates four IEEE MAC assignments registered to legally distinct entities within one Chinese electronics-manufacturing group: DBG Technology Co., Ltd. (Chinese legal name 惠州光弘科技股份有限公司, Huizhou Guanghong Technology Co., Ltd.), a publicly-listed EMS (electronics manufacturing services / contract manufacturer) on the Shenzhen Stock Exchange under ticker 300735. Two MA-L blocks and two MA-M (28-bit) sub-allocations span China and Hong Kong: D4:73:50 and the MA-M 78:78:35:C/28 both trace to the Daya Bay / Huizhou factory entity (the MA-L block's registered name carries a verbatim IEEE typo, "DBG Commnunications Technology Co., Ltd."), E4:92:2A belongs to the Hong Kong holding entity "DBG HOLDINGS LIMITED" in Fo Tan, and 74:33:36:3/28 belongs to "Shenzhen DBG Innovation Tech Limited" in Bao'an. The asset-identification consequence is the important part: DBG is a contract manufacturer that builds for OEM clients (reported clients include Huawei, Honor, and Xiaomi) rather than selling under its own brand. A DBG OUI on a device therefore most likely identifies hardware DBG assembled for an OEM, and the OEM brand label — not the DBG MAC block — is the authoritative identifier for firmware and vulnerability tracking. IEEE publishes no registration dates for any of these blocks; a third-party date (maclookup.app shows 2021-04-29 for D4:73:50) is a database artifact, not an IEEE fact.

IEEE assignment (MA-L)

D4:73:50 → "DBG Commnunications Technology Co., Ltd." (IEEE typo "Commnunications" is verbatim), Building A, No. 5 (DBG Factory), Yongda Road, Xiangshui River, West District of Daya Bay, Huizhou, Guangdong, CN 516083 [Confirmed] — IEEE MA-L (oui.csv:906)

IEEE assignment (MA-L)

E4:92:2A → "DBG HOLDINGS LIMITED", Unit D, 6/F., Unison Industrial Centre, 27-31 Aupui Wan Street, Fo Tan, N.T., Hong Kong, HK 999077 [Confirmed] — IEEE MA-L (oui.csv:25274)

IEEE assignment (MA-M, 28-bit)

78:78:35:C → "DBG Communications Technology Co.,Ltd." (covers 78-78-35-C0-00-00 through 78-78-35-CF-FF-FF; a /28 sub-allocation of the shared 78:78:35 MA-M base — sibling /28s belong to unrelated orgs), same Daya Bay/Huizhou address [Confirmed] — IEEE MA-M (mam.csv:6307)

IEEE assignment (MA-M, 28-bit)

74:33:36:3 → "Shenzhen DBG Innovation Tech Limited" (covers 74-33-36-30-00-00 through 74-33-36-3F-FF-FF; /28 sub-allocation of the 74:33:36 MA-M base), Unit 301, Building C, Qianwan Key & Core Technology Industrial Park, Xixiang, Bao'an, Shenzhen, Guangdong, CN 518103 [Confirmed] — IEEE MA-M (mam.csv:6343)

Registry / block sizes

2× MA-L (24-bit OUI) + 2× MA-M (28-bit); 4 prefixes total; no MA-S (oui36.csv) matches [Confirmed] — IEEE oui.csv, mam.csv, oui36.csv

Primary org / country

DBG Communications Technology Co., Ltd. (Huizhou, Guangdong, CN); related HK holding entity DBG HOLDINGS LIMITED (Hong Kong, HK); related subsidiary Shenzhen DBG Innovation Tech Limited (Shenzhen, CN) [Confirmed] — IEEE oui.csv/mam.csv

Company overview

DBG Technology Co., Ltd. (惠州光弘科技股份有限公司), publicly listed on the Shenzhen Stock Exchange (300735), EMS/contract manufacturer founded 1995, HQ at No. 5 Yongda Road, Xiangshui River Industrial Area, Daya Bay, Huizhou, Guangdong, CN 516083; ranks among the top global EMS providers [Confirmed] — dbg.ltd, stockanalysis.com (300735)

Company status

active — listed (300735.SZ) as of June 2026, active website, ongoing manufacturing expansion (Shenzhen Pingshan park topped out 2024–2025) [Confirmed] — stockanalysis.com, dbg.ltd

Device types

contract-manufactured (no own brand) — smartphones, smart consumer terminals, communications/networking equipment (CPE, routers, base-station components), automotive electronics, new-energy/solar, AI/computing, medical; built for OEM clients incl. Huawei, Honor, Xiaomi [Likely] — dbg.ltd/our-markets/communications, dbg.ltd

Registration date

Unknown / null — IEEE publishes NO assignment date for OUI or MA-M prefixes (oui.csv/mam.csv columns are only Registry, Assignment, Organization Name, Organization Address). maclookup.app's 2021-04-29 for D4:73:50 is a database artifact, not an IEEE fact [Confirmed] — IEEE oui.csv/mam.csv; maclookup.app/macaddress/D47350

IANA reference

none (OUI/MAC entries carry no IANA reference) [Confirmed]

Website

https://www.dbg.ltd/ (primary English site; also www.dbg.com.cn, www.dbgsz.com.cn) [Confirmed] — dbg.ltd

Security context

no CVEs or public vulnerability disclosures found naming any DBG entity (NVD/CISA/CVE searches returned no matches); EMS-class posture — vulnerabilities in DBG-built networking gear are tracked under the OEM brand (e.g., Huawei), not DBG [Likely] — cve.org, nvd.nist.gov

Disambiguation note

all four prefixes share the "DBG" brand but are registered to legally distinct entities across two jurisdictions; the Huizhou/Daya Bay factory entity holds both the D4:73:50 MA-L and the 78:78:35:C MA-M blocks (the MA-L name has the "Commnunications" typo, the MA-M is spelled correctly) [Likely] — IEEE oui.csv/mam.csv

Slug note

the site's normaliseName() will bucket these distinct registrant names into separate slugs (e.g. dbg-commnunications-technology, dbg-holdings, shenzhen-dbg-innovation-tech); "vendor-dbg" is a consolidated research handle, not a generated page slug — build team must decide consolidation vs. separate pages

Analyst note

A DBG OUI (D4:73:50, E4:92:2A, 78:78:35:C/28, 74:33:36:3/28) identifies hardware built by the DBG contract-manufacturing group, most likely under an OEM contract (Huawei/Honor/Xiaomi). The device brand label, not the DBG MAC assignment, is the authoritative identifier for firmware/version and vulnerability tracking; DBG is not a branded networking-gear vendor.