Foxconn Technology Group is the trading name of Taiwan's Hon Hai Precision Industry Co, the main assembler of Apple Inc devices.
Qualcomm said its licensing agreements with the aforementioned manufacturers date back to before Apple even sold its first iPhone - and that Apple isn't even a party in those contracts.
The Cupertino, California, company isn't alone in its accusations against Qualcomm.
"Their gripe, their issue, appears to be with Apple", said Qualcomm General Counsel Don Rosenberg.
Qualcomm previously sued Apple accusing it of breaking contracts and interfering in deals negotiated with iPhone suppliers.
"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", Qualcomm said on Wednesday.
Manufacturers that build Apple's iPhone and iPad are being drawn in to an escalating dispute between the tech giant and the chipmaker Qualcomm.
The aforementioned contract manufacturers have stopped paying royalties they owe Qualcomm for the licensing of certain technology used on Apple's handsets and tablets.
Earlier this year the FTC filed a lawsuit against Qualcomm over alleged antitrust violations.
Qualcomm's patent-licensing segment in fiscal 2016 contributed roughly 80% of its pretax profit.
The case underscores the influence Apple wields over the companies that make its products and parts for them. Apple counters that Qualcomm has been abusing its power in the mobile chip market to charge for royalties on features that aren't covered by its patents. "As we've said before, Qualcomm's demands are unreasonable and they have been charging higher rates based on our innovation, not their own".
The company has sued the manufacturers for allegedly breaching their licence agreements by failing to pay royalties on the use of Qualcomm's technology in the assembly of Apple iPhones. The two companies have sued and countersued each other since January. With the contractors in turn not paying Qualcomm - at Apple's direction, Qualcomm says - the chipmaker last month was forced to slash third-quarter forecasts because it's unclear when the royalties will be paid.
Several other companies and trade associations seem to be of similar mind and have also filed briefs supporting the FTC. "You are responsible for paying that".
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