AT&T Inc. is an American multinational telecommunications conglomerate. It is the second largest provider of mobile telephone services in the US.

CMCC is China's largest mobile telecommunications companies by market capitalization.

China Telecom is the largest fixed-line service and the second largest mobile telecommunication provider in China.

China United Network Communications Group is one of the three largest mobile telecommunication providers in China.

KT Corporation is South Korea’s largest telephone company. It dominates the local landline and broadband Internet market.

Movistar is the major Spanish mobile phone operator owned by Telefónica S.A. operating in Spain and in many Latin American countries.

Orange is one of the largest operators of mobile and internet services in Europe and Africa.

SK Telecom is the largest wireless carrier in South Korea. It leads the local market with 50.5 percent share as of 2008.

Telefónica, S.A. is a Spanish broadband and telecommunications provider with operations in Europe, Asia, North and South America.

Telcel is a Mexican wireless telecommunications company, it is the leading provider of wireless communications services in Mexico.

Telstra is Australia’s largest telecommunications and media company which builds and operates telecommunications networks.

T-Mobile USA, a subsidiary of Germany-based Deutsche Telekom, provides wireless voice and data communications services in the US.

Verizon is a broadband telecommunications company and the largest U.S. wireless communications service provider as of Sept 2014.

Vodafone is a British telecom company. It owns and operates networks in 21 countries and has partner networks in over 40 additional countries.

Links Field, a leading IoT connectivity solution Provider, is committed to multi-SIM solutions, reliable and resilient connectivity and manager platform.

A European consumer protection program designed to certify that products have met health, safety, and environmental requirements.

The FCC regulates interstate and international communications by radio, television, wire, satellite, and cable in all 50 states in the U.S.

The Global Certification Forum (GCF) is an independent certification scheme for mobile phones and wireless devices that are based on 3GPP standards.

ICASA is the regulator for South African communications, broadcasting and postal services sector.

PTCRB provides the framework within which GSM Mobile Equipment (ME) Type Certification can take place for members of the PTCRB.

RCM indicates a product's compliance with all applicable ACMA regulatory arrangements in Australia and New Zealand.

ANATEL, Brazil's regulating agency, requires certification to commercialize telecommunication equipment in Brazil.

Industry Canada (IC) provides certification services for radio devices launched in Canada. The testing is usually done by 3rd-party labs.

Qualcomm Incorporated is an American global semiconductor company that designs and markets wireless telecom products and services.

MediaTek Inc. is a fabless semiconductor company that provides system-on-chip solutions for wireless communications, HDTV and DVD.

STMicroelectronics is one of the world’s largest semiconductor companies with net revenues of US$ 9.56 billion in 2019. Offering one of the industry’s broadest product portfolios, ST serves customers across the spectrum of electronics applications with innovative semiconductor solutions by leveraging its vast array of technologies, design expertise and combination of intellectual property portfolio, strategic partnerships and manufacturing strength.

Arm was founded by a dozen engineers working from a converted barn in Cambridge, UK. Arm gives its people the capabilities, processes and infrastructure to enable them to develop and thrive as the business scales and strengthens.

Seven Layers IT Solutions has been designing, deploying and supporting data networks for the public and private sectors.

SGS is a multinational company headquartered in Geneva, Switzerland which provides inspection,verification, testing and certification services.

SRTC, subordinate to China's State Radio Monitoring Center, specializes in various work, including testing and certification of radio technology.

Compliance Certification Services Inc. is experienced in professional certification fields of performance testing capabilities in EMC, RF, SAFETY, DFS, SAR, HAC, Automotive EMC, OTA and Digital TV.

China Telecommunication Technology Labs focuses on setting standards, and carrying out tests on technical feasibility and standards compliance.

Sporton is a designated testing lab for regulatory bodies such as TAF and acquired professional certificates including PTCRB, GCF and CTIA.