Founded in 1985, Qualcomm is known for inventing a digital wireless technology called Code Division Multiple Access.

CDMA eventually became the core of some mainstream 3G telecom standards such as Wideband Code Division Multiple Access.

Its competitiveness has extended to the 4G stage, because, in the short term, Qualcomm has no rivals in Long-Term Evolution 4G chipsets.

Under China's Antimonopoly Law, the NDRC can impose fines of 1 to 10 percent of a company's revenue from the previous year.

That means Qualcomm could face up to $1.23 billion in fines if it's found to have broken the law. Even at the lowest rate, it would be $123 million.

The highest fine imposed by the NDRC so far was in August last year, when the regulator fined six infant formula manufacturers — including Mead Johnson Nutrition Co, Groupe Danone and Fonterra Co-operative Group Ltd — a total of $110 million after a probe into price-fixing and anti-competitive practices.

Experts said the exact amount of fines still hinges on how negotiations proceed. Qualcomm might have to make concessions on its royalties if it wants to achieve a low fine.

The NDRC also confirmed it started an investigation of InterDigital last May. It said the company had applied to halt the probe after months of active cooperation.

Xu said the bureau is considering InterDigital's request and stressed a condition of doing so is that the company promises to address the issues.

The wireless research and development company issued a statement on Friday, saying InterDigital executives had "indicated to the NDRC their apologies that the company had misunderstood Chinese law and the NDRC's rules and procedures in that regard".

InterDigital reaps a majority of its revenue from patent licensing. It has ongoing legal proceedings with Huawei in the US, Europe and China.

The NDRC has ramped up its antitrust efforts and put many companies on its scrutiny list. It has probed charges and price manipulation in a number of industries, including banks, milk formula and telecommunications.

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