The Taiwan Fair Trade Commission unveiled that Qualcomm blocked Samsung Electronics from selling its integrated mobile chipset "Exynos" to third parties.
On the other hand, Qualcomm's own SnapDragon chips have been widely used in many smartphones, including those from LG Electronics, Huawei, and Xiaomi.
Given that Exynos and SnapDragon SoCs typically offer the same performance, it was generally believed that Samsung refrained from supplying Exynos to others in order to protect its own IP and technology. However, FTC claims that Samsung attempted to sell Exynos chipsets to others but Qualcomm blocked the South Korean company.
FTC said that Qualcomm abused the "standard essential patent" license to prevent Samsung from selling its modems and integrated chipsets for about 25 years. The unfair practice was confirmed in the Fair Trade Commission's resolution related to Qualcomm's actions that abused its market power to thwart rivals.
"Samsung Electronics has been blocked from selling its modem chipsets to other smartphone manufacturers due to a license deal it signed with Qualcomm," the FTC said.
Qualcomm did not provide any comment.
Qualcomm faces legal challenges across the globe. South Korea's antitrust regulator fined Qualcomm 1.03 trillion won ($854 million) in December for what it called unfair practices in patent licensing, a decision the U.S. chipmaker said it will challenge in court.
In February 2015, Qualcomm paid a $975 million fine in China following a 14-month probe, while the European Union in December 2015 accused it of abusing its market power to thwart rivals.