Qualcomm is stepping up its legal spat against Apple.

The world's largest mobile chip maker filed several lawsuits against Apple in China, seeking to stop the sale and manufacturing of iPhones in the country. Qualcomm is claiming that Apple is illegally using its intellectual property in its justification, according to Bloomberg.

Apple and Qualcomm didn't respond to requests for comment.

This is the latest move in a legal battle between Apple and Qualcomm that's gone on for months. The companies are in a disagreement over how much Apple should pay for the radio chip it uses to power the iPhone's cellular connection. Apple thinks Qualcomm charges too much. Qualcomm believes Apple isn't recognizing the other technologies that go into the component.

The crux of the disagreement is this: The world's biggest provider of mobile chips created technology to connect phones to cellular networks. Qualcomm gets a significant portion of its revenue from licensing its technologies to hundreds of device makers, with the fee based on the value of the phone, rather than individual components. Because Qualcomm owns patents related to 3G and 4G phones, any phone maker building a device that connects to 3G or 4G networks has to pay it a licensing fee, even if it doesn't use Qualcomm's chips.

That includes Apple, which thinks it should pay a fee based only on the value of Qualcomm's connectivity chips, not the entire phone. It says Qualcomm is "effectively taxing Apple's innovation" and that Apple "shouldn't have to pay them for technology breakthroughs they have nothing to do with."

Qualcomm also makes the processor for marquee phones like the Samsung Galaxy Note 8 and LG V30.

CNET senior reporter Shara Tibken breaks down the dispute here.