American chip company Qualcomm has accused smartphone giants of stealing its information and giving it to rival chip makers, Intel.

“Apple has engaged in a years-long campaign of false promises, stealth, and subterfuge designed to steal Qualcomm’s confidential information and trade secrets for the purpose of improving the performance and accelerating time to market of lower-quality modem chipsets, including those developed by Intel Corporation, competitor of Qualcomm, to render such chipsets useable in Apple iPhones and other devices, with the ultimate goal of diverting Qualcomm’s Apple-based business to Intel,” Qualcomm wrote in a proposed amended complaint.

Apple has separately accused Qualcomm of abusing its market dominance in microchips.

Its objections centre around the fees charged by Qualcomm for its technology.

For years, Qualcomm supplied Apple with items such as processors for its iPhones and other hardware, but iPhone maker has favoured Intel more recently.

In the new court filing, Qualcomm said Apple engineers supplied Intel staff with Qualcomm’s confidential source code with the aim of improving the performance of Intel chips, despite a contract intended to restrict access to the technology.

“Apple has wrongfully acquired, failed to protect, wrongfully used, wrongfully disclosed, and outright stolen Qualcomm’s confidential information and trade secrets, and Apple used that stolen technology to divert Qualcomm’s Apple-based business to Intel,” Qualcomm alleged.

The new iPhone XS and XS Max use Intel modem chips.

Qualcomm alleged the move was part of an “intricate plan” developed by Apple over several years, with the aim of cutting costs and increasing its leverage over Qualcomm.

Starting in 2010, Qualcomm gave Apple “access to large portions of Qualcomm software, including the most sensitive and important layers of source code for Qualcomm’s industry‐leading modem,” Qualcomm’s complaint said.

This was “unprecedented access,” demanded by Apple, which said it needed the source code “to modify and integrate the code to enable Qualcomm chipsets to work in Apple devices, including iPhones,” Qualcomm said.

To get the code, Apple agreed “to take a number of steps to ensure and maintain the confidentiality and security of Qualcomm’s software, including source code,” pursuant to the master software agreement, Qualcomm wrote.

The breach has caused damages “including, but not limited to lost profits”, while “unjustly” enriching Apple, the filing says.

Qualcomm is seeking to add the claims to a lawsuit first filed last year.

The initial complaint alleged that Apple violated the terms of their contract, including by resisting Qualcomm’s efforts to audit its compliance.

Separately, Qualcomm has also accused Apple of violating its patents.

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