According to a new report from Reuters, Apple has filed a lawsuit against Ericsson because of a disagreement regarding royalties for an LTE wireless chip that Apple used in the first iPhone.

However, Apple spokespersonKristin Huguet has said Apple is happy to pay royalties to the Swedish technology firm: “We’ve always been willing to pay a fair price to secure the rights to standards essential patents covering technology in our products. Unfortunately, we have not been able to agree with Ericsson on a fair rate for their patents so, as a last resort, we are asking the courts for help.”

The disagreement comes from the fact that Ericsson seems to be getting the numbers for the payments from the total cost of the device (the whole iPhone handset), rather than the chip used in it. Apple claims that this makes for an unfair price for the technology.