SEOUL-- South Korea's highest court has rejected U.S. mobile phone chipmaker Qualcomm Inc.'s call to suspend the implementation of corrective measures taken by the country's anti-trust watchdog, the Fair Trade Commission said Tuesday.

In December last year, the FTC slapped Qualcomm with a record fine of 1.03 trillion won (US$951 million) for abusing its dominant position in the mobile communications market and ordered it not to sign unfavorable terms with customers.

The FTC said the San Diego-based company and its two affiliates breached the country's competition act by refusing to offer licenses to chipset manufacturers and demanding high fees for patents used by smartphone makers.

Calling the FTC ruling "unprecedented and insupportable," Qualcomm took the case to the Seoul High Court in February this year, but the court rejected it in September. The U.S. firm again appealed to the country's highest court.

The watchdog said the mobile communications market consists of three sub-markets -- patent license, modem chipset and mobile phone -- and Qualcomm wields its monopolistic control in the former two markets and highly influences the third.

Qualcomm holds a majority share of standard essential patent rights in code division multiple access (CDMA) and long term evolution (LTE) standards, posting $7.95 billion in license royalties in 2015.

The FTC said the company refused to offer patent rights to chipset makers and forced them to sign unfavorable contracts that demand they report business information to Qualcomm.

It also did not provide Qualcomm-chartered chipsets to mobile phone makers when they refused to comply with Qualcomm's license policy and demanded the manufacturers share their patent rights for free.

The watchdog launched the probe to review the U.S. firm's practices in 2014, with many global chipmakers and handset manufacturers including Intel Corp. and Samsung Electronics Co. having participated in the hearing.

The FTC's ruling came after the Chinese corporate watchdog levied a fine of 1 trillion won on Qualcomm for forcing excessive royalties in 2015.

Source: Yonhap News Agency