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Quoted from Wikipedia:
Hutchison Whampoa owns direct majority interests in the companies that operate the networks that are branded 3, except 3 Hong Kong and 3 Indonesia. These networks are majority-owned by the publicly listed Hutchison Telecommunications International Limited (HTIL), in which Hutchison Whampoa has a 50.003 percent majority interest.
All 3-branded networks provide 3G technology (WCDMA, some also run 2G networks). Hutchison Whampoa also holds a 3G-license in Israel which operates under the brand Orange, and in Norway which is not operational yet. As of 20 August 2008, registered 3 customers worldwide numbered over 19 million.