Qualcomm said in a lawsuit filed in California state court in San Diego that Apple used its economic leverage to demand unprecedented access to the chipmaker’s highly confidential software, including source code.

Apple started using Intel’s broadband modem chips in the iPhone 7, mostly to punish Qualcomm for not lowering its prices.

In its complaint, Qualcomm alleged that Apple was needed under its contract to ensure that Apple engineers working with Qualcomm did not communicate details about Qualcomm chips to Apple engineers working on competing chips from Intel.

Qualcomm alleged that in July, Apple emailed Qualcomm to request “highly confidential” information about how its chips work on an unidentified wireless carrier’s network. Apple copied an Intel engineer in the email for information, Qualcomm alleged.

Qualcomm alleged that an Apple engineer working on a competing chip asked an Apple engineer working with Qualcomm to get technical information from Qualcomm.

Apple has announced that it will drop Qualcomm’s chips from its iPhones and iPads beginning next year.