The other manufacturers listed by Qualcomm were Pegatron, Wistron, and Compal Electronics.

The iPhone maker sued Qualcomm (QCOMM) in January, accusing it of overcharging for chips and refusing to pay some $1 billion in promised rebates.

Qualcomm said last month that Apple (AAPL) had decided to withhold royalty payments to its contract manufacturers that are owed to the chipmaker, for sales made in the first quarter of 2017, until the dispute is resolved in court.

“While not disputing their contractual obligations to pay for the use of Qualcomm’s inventions, the manufacturers say they must follow Apple’s instructions not to pay,” the chipmaker said in a statement.

Qualcomm said it sought an order that would require the manufacturers to comply with their long-standing contractual obligations to the company, as well as declaratory relief and damages.

The chipmaker slashed its current-quarter profit and revenue forecasts in April, saying it excluded revenue receivable from those contract manufacturers.

Qualcomm, the largest maker of chips used in smartphones, is a major supplier to Apple and Samsung Electronics (SSNLF) for modem chips that connect phones to wireless networks.

Foxconn Technology (FXCNY) is the trading name of Taiwan’s Hon Hai Precision Industry, the main assembler of Apple devices.

Qualcomm filed the complaint in the United States District Court for the Southern District of California.

The company’s shares were marginally lower at $55.49 in premarket trading.