Less than three months after being sued by Apple for $1 billion, chipmaker Qualcomm is countersuing the iPhone maker in a dispute over licensing fees for mobile technology.
Qualcomm said on Monday that it filed its answers and counterclaims to the suit, seeking unspecified damages and to "enjoin Apple from further interference with Qualcomm's agreements with the companies that manufacture iPhones and iPads for Apple."
The legal battle is the centerpiece of a high-stakes dispute between the world's most valuable company and the leading maker of processors in mobile phones. Qualcomm makes money from the chips themselves as well as from royalties when any device is sold that's based on its cellular standards. One-third of Qualcomm's revenue comes from licensing.
Apple claimed in January that Qualcomm has been charging royalties for "technologies they have nothing to do with."
Qualcomm said in its press release that the countersuit outlines how Apple breached and mischaracterized agreements and negotiations, interfered with agreements with device manufacturers, encouraged regulatory attacks against Qualcomm around the world, opted "not to utilize the full performance of Qualcomm's modem chips in its iPhone7," and threatened Qualcomm to keep it from speaking publicly about the better performance of iPhones with Qualcomm chips.
"Apple could not have built the incredible iPhone franchise that has made it the most profitable company in the world, capturing over 90 percent of smartphone profits, without relying upon Qualcomm's fundamental cellular technologies," Qualcomm said. "Now, after a decade of historic growth, Apple refuses to acknowledge the well established and continuing value of those technologies."
Part of the initial claim was that Qualcomm withheld nearly $1 billion from Apple as a retaliatory measure after Apple helped the Korean authorities in an antitrust investigation. Apple's business agreement with Qualcomm has included rebates from the chipmaker for
Qualcomm CEO Steven Mollenkopf said in February at a Goldman Sachs conference in San Francisco that he prefers the matter to be settled out of court and that, "you're probably not going to see us argue this out in press."
The suit was filed in the U.S. District Court for the Southern District of California.
--CNBC's Jon Fortt contributed to this report.
(Clarification: This story was updated to say that Qualcomm licenses mobile technology beyond just chips.)