The regulator said that Apple Asia, a unit of the Cupertino-based company, required carriers to obtain its permission before setting contract prices on iPhones in violation of Taiwan's free-trade laws.
Apple Asia also told carriers to alter service contract prices and subsidy prices, according to an FTC statement on Wednesday, leading to the fine of T$20 million.
Officials with Apple Asia could not be reached for comment on Thursday.
The three carriers, Chunghwa Telecom Co Ltd, Taiwan Mobile Co Ltd and Far EasTone Telecommunications Co Ltd, had all obtained reseller rights under their contracts with Apple, which gave them the right to set prices, FTC spokesman Sun Lih-chyun said.
Apple has been facing challenges in the rapidly-evolving marketplace for the smartphones in which it once held a commanding lead.
The company recently reported that it signed a long-awaited deal with China Mobile Ltd, China's largest telecom carrier, to sell its iPhones, raising hopes that it may make significant inroads in the world's largest smartphone market.
(Also see: Apple inks China Mobile deal, gets 760 million new potential iPhone customers)
© Thomson Reuters 2013
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