(Reuters) - Chipmaker Intel Corp has filed an antitrust lawsuit against a SoftBank Group Corp-owned investment company alleging the firm stockpiled patents to hold up technology companies with numerous lawsuits.

FILE PHOTO: The Intel logo is displayed on computer screens at SIGGRAPH 2017 in Los Angeles, California, U.S. July 31, 2017. REUTERS/Mike Blake

The complaint filed late Monday in the U.S. District Court for the Northern District of California in San Jose alleged that Fortress Investment Group, which SoftBank bought in 2017 for $3.3 billion, acquired control of more than 1,000 U.S. technology patents.

Intel said that Fortress and other companies it owns or controls filed lawsuits against the Santa Clara chipmaker claiming that nearly every Intel processor made since 2011 infringed patents the companies had obtained control of from NXP Semiconductors.

“One way in which Fortress has tried to turn around its performance and justify SoftBank’s investment in it is through increased speculation on patent assertions,” the lawsuit said.

“Intel brings this complaint to end a campaign of anticompetitive patent aggregation by Fortress and a web of (patent assertion entities) that Fortress owns or controls.”

Gordon Runté, a managing director at Fortress, said in a statement that the company is “confident in our business practices and our legal position and view this lawsuit as meritless, but we don’t comment on the specifics of litigation matters.”

SoftBank declined to comment, and Intel declined to comment beyond its filings.

SoftBank also owns Arm Holdings, a British chip firm whose technology is making inroads on key Intel markets such as personal computers and data centers.

Intel said Fortress’ efforts to gather patents constituted anticompetitive behavior because they were driven by the idea that its purchases would cost less than what technology companies would pay to avoid lawsuits.

“Fortress’ aggregation is intended for an anticompetitive purpose—to invest in patents at costs lower than the holdup value of the patents,” Intel wrote in its complaint.