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KDDI Corporation
Native name
Keidīdīai kabushiki gaisha
Company typePublic KK
TYO: 9433
TOPIX Core 30 Component
Founded1953; 71 years ago (1953) (establishment of Kokusai Denshin Denwa or KDD as a state-owned enterprise)[1][2]
FounderGovernment of Japan (for the KDD branch)
Kazuo Inamori (for the DDI branch)
HeadquartersChiyoda, Tokyo, Japan
Key people
Takashi Tanaka(businessman) [jp], CEO
Makoto Takahashi(businessman) [jp], President & CEO
ProductsFixed line and mobile telephony, Internet services, digital television
RevenueIncrease JP¥ 5.24 trillion (2020)[3]
Increase JP¥ 639.77 billion (2020)[3]
Number of employees
44,952 (2020)[3]
  • Okinawa Cellular Telephone Company (53.9%)
  • JCOM (50%)
  • UQ Communications (32.3%)
  • Aeon Holdings
  • Chubu Telecomunications
  • Wire and Wireless
  • Telasa (50%)
  • au Financial Holdings
  • Supership Holdings
  • au Energy Holdings
  • KDDI Matomete Office
  • KDDI Digital Divergence Holdings
  • KDDI Engineering
  • KDDI Research
  • KDDI Cableships & Subsea Engineering
  • Japan Telecommunication Engineering Service
  • KDDI America
  • KDDI China
  • KDDI Asia Pacific
  • Telehouse Holdings
  • Kyocera Communication System (23.4%)
  • Mobaoku (33.4%)
  • (17.4%)
  • Lac (32.4%)

KDDI Corporation (KDDI株式会社, KDDI Kabushiki Gaisha) (TYO: 9433) is a Japanese telecommunications operator. It was established in 2000 through the merger of DDI (第二電電, Daini Denden), KDD (ケイディディ), and IDO (日本移動通信, Nippon Idō Tsūshin). In 2001, it merged with a subsidiary named Au, which was formed through the merger of seven automotive and mobile phone companies from the DDI-Cellular Group. As of 2020, it is the second-largest mobile telecommunications provider in Japan in terms of the number of contracts, following NTT Docomo.

KDDI provides mobile cellular services using the Au brand. ISP network services are provided under the au one net brand, while "au Hikari" is the name under which long-distance and international voice and data communications services and Fiber to the Home (FTTH) services are marketed. ADSL broadband services carry the brand name "ADSL One", and IP telephony over copper is branded as "Metal Plus".


On April 1, 2002, au by KDDI launched 3G networks using CDMA2000 1x technology.[citation needed]

On November 28, 2003, au by KDDI launched EV-DO Rev 0 service in the "CDMA 1X WIN" brand, and revolutionized Japan's mobile telecommunication industry by introducing fixed rate data subscription plans at a data rate of 2.4 Mbit/s.[citation needed]

In December 2006, au by KDDI became the first carrier to provide an EV-DO Rev A service at a data rate of 3.1Mbit/s (downlink), 1.8Mbit/s (uplink).[citation needed]

au by KDDI has been very successful with its EZ wireless data services, EZweb, EZweb@mail, EZappli, EZchakuuta, ezmovie, and EZnaviwalk (GPS), using the advanced WAP technology. It supports both Java ME and BREW application environments.[citation needed]

In November 2004 au by KDDI introduced the music include ringtone download service Chaku Uta Full (music ringtone full), for download of full length songs to mobile phones. Within six months from introduction, on June 15, 2005, customers had downloaded 10 million full length Chaku Uta Full songs.[citation needed]

As of end of June 2005, au by KDDI has 20,122,700 customers, among which 18,723,200 (93%) are 3G CDMA2000 subscribers. It is Japan's second-largest cellular operator with an increasing 20.0% market share.[citation needed]

On January 26, 2006, the first pointing local search application, Mapion Local Search - Powered by GeoVector, was launched on the KDDI network on their GPS and compass equipped handsets.[4] In January 2007, KDDI announced its ten new 3G models for spring 2007, and a concept of its new designer phone Media Skin by Tokujin Yoshioka which would later be displayed at the Museum of Modern Art in New York with the Infobar, Talby and Neon models. Toshiba, Casio, Sanyo, Kyocera, Hitachi, Sony Ericsson, Sharp, and Panasonic have manufactured the other models.[5] In March 2007, Media Skin started selling.[6]

KDDI announced that it would collaborate with the Taiwanese manufacturer HTC Corp. to sell the mobile phone HTC J in Japan starting May 2012. The HTC J mobile phone featured the Android 4.0 operating system.[7][8]

On October 21, 2011, KDDI buys Content Delivery Network CDNetworks For $167 Million.[9]

KDDI together with Sumitomo Group signed an agreement with Myanmar State owned Myanmar Post and Telecommunication (MPT) in July 2014 to jointly operate a mobile phone service in Myanmar for next 10 years.[10]

Consumer showroom is set in Harajuku called, "KDDI Designing Studio".

TU-KA (TU-KA by KDDI), a subsidiary company of KDDI, was a 2G PDC cellular operator in three metropolitan areas (Tokyo, Nagoya, and Osaka), which did not apply a 3G license. TU-KA was best known for having singer Ayumi Hamasaki to appear in their commercials. TU-KA was closed on March 31, 2008.

DDI Pocket, a PHS operator, was previously owned by KDDI but was spun off as Willcom which is now incorporated into Y!Mobile.

In August 2014, KDDI announced it was joining forces with five other global companies, including Google to build a 60Tbit/s undersea data transmission cable linking the United States West Coast and Japan.[11] The cable started operation in June 2016.[12]

KDDI and Ericsson began working together in December 2015 in order to research and develop 5G technology.[13]


In 2003, several class action complaints were filed against DDI for misrepresenting and/or failing to disclose material facts about the company's financial results.[14] The parties agreed on a $4.4 million settlement in 2006.[15]

See also

References and footnotes

  1. ^ "KDDI Corporation: Private Company Information". Retrieved 6 May 2018.
  2. ^ "History | About KDDI". Retrieved 6 May 2018.
  3. ^ a b c "KDDI Annual Report" (PDF) (Press release). Retrieved February 17, 2021.
  4. ^ "GeoVector: Press Room". Archived from the original on January 16, 2009. Retrieved April 22, 2009.
  5. ^ "Wireless Watch Japan". Wireless Watch Japan - Mobile in Tokyo. Retrieved 2019-04-01.
  6. ^ Chen, Jason (17 January 2007). "Japan Watch: Media Skin Cellphone". Gizmodo. Retrieved 2019-04-01.
  7. ^ "Brightwire". Brightwire. Archived from the original on 2013-01-18. Retrieved 2016-03-28.
  8. ^ "HTC and KDDI to sell HTC J". BrightWire. Archived from the original on 2013-01-18.
  9. ^ "Japanese Telco KDDI Buys Content Delivery Network CDNetworks For $167 Million". Techcrunch. October 21, 2011.
  10. ^ "KDDI, Sumitomo ink deal with Myanmar telecom for mobile phone service". The Japan Times. 17 July 2014. Retrieved 17 July 2014.
  11. ^ "High-speed Undersea Cable to Link US, Asia". The Tokyo News.Net. 12 August 2014. Retrieved 13 August 2014.
  12. ^ "Google Cloud customers run at the speed of light with new faster undersea pipe". Retrieved 30 May 2017.
  13. ^ Dan Kobialka (2015-12-01). "Ericsson, KDDI Partner for 5G Research and Development". Telco Hub content from Talkin' Cloud. Archived from the original on 2016-05-05. Retrieved 2016-03-28.
  14. ^ "Class action suit filed vs DDI". Archived from the original on 2016-03-05. Retrieved 2013-07-19.
  15. ^ "Notice of pendency and proposed settlement of class action" (PDF).