Chip maker seeks damages; claims Apple made false statements to regulators, crippled performance of its modem chips.

Qualcomm late on Monday filed a countersuit against Apple, alleging that the device maker made false statements to regulators, breached agreements, and deliberately limited the performance of its modem chips in the iPhone 7.

The chip maker also claims that Apple interfered with agreements between Qualcomm and Qualcomm licensees that manufacture iPhones and iPads. Apple is also accused of misrepresenting facts in order to encourage regulatory attacks on Qualcomm in other countries.

"[Apple] has launched a global attack on Qualcomm and is attempting to use its enormous market power to coerce unfair and unreasonable license terms from Qualcomm," said Don Rosenberg, EVP and general counsel, Qualcomm.

"We intend to vigorously defend our business model, and pursue our right to protect and receive fair value for our technological contributions to the industry," he said.

Perhaps the most serious accusation levelled at Apple is that it deliberately chose to not use the full performance of Qualcomm’s modem chips in the iPhone 7, and misrepresented the performance disparity between iPhones using Qualcomm chips, and those using competitor-supplied chips.

Qualcomm claimed that Apple threatened it in an attempt to prevent Qualcomm from making any public comparisons about the superior performance of the Qualcomm-powered iPhones.

"Apple could not have built the incredible iPhone franchise that has made it the most profitable company in the world, capturing over 90% of smartphone profits, without relying upon Qualcomm’s fundamental cellular technologies," Rosenberg insisted.

Qualcomm’s blistering attack was launched after Apple sued Qualcomm for $1 billion in January, accusing the company of having an abusive licensing model designed to extract excessive royalties in return for using Qualcomm’s patented technology.