Qualcomm has been ordered to make patents essential for modern modem chips available to rival companies.
On Tuesday in the US District Court for the Northern District of California, Judge Lucy Koh granted a partial summary judgment against Qualcomm which was requested by the US Federal Trade Commission (FTC).
This requires Qualcomm to open up some of its portfolio of essential patents to rival companies such as Intel.
The intellectual property in question relates to some of the US chip maker's patents which protect core technologies essential for chips which permit mobile devices to connect to wireless systems.
The judgment was made as part of an antitrust lawsuit levied against Qualcomm by the FTC. The court case was launched in 2017 and is set to reach the trial stage next year.
"Undisputed evidence in Qualcomm's own documents demonstrates that a modem chip is a core component of the cellular handset, which only underscores how a [standard essential patent] license to supply modem chips is for the purpose of practicing or implementing cellular standards and why Qualcomm cannot discriminate against modem chip suppliers," Koh wrote, as reported by sister site CNET.
Qualcomm and the FTC had jointly requested a delay to ruling in order to explore settlement options -- a request Koh denied.
This court case is running parallel to a legal battle between Qualcomm and Apple. The two tech giants have been clashing for years over licensing, with the former claiming that the iPad and iPhone maker owes $7 billion in patent licensing fees -- while the latter says that Qualcomm is operating an "illegal" business model.
Apple has disputed the amount owing, adding that Qualcomm is 'double dipping' by charging a license fee not only for the technology used in iPhones but also for each device which is manufactured.
Qualcomm has countered, claiming that Apple is also using a number of the firm's patents outside of agreed licensing contracts.
ZDNet has reached out to Qualcomm and will update if we hear back.