Apple and Ericsson’s dispute over pricing for patent licensing related to mobile telecommunications has been going on for a while now. The iPhone maker is now reported to have filed a lawsuit against the latter, claiming that the company employed “strong-arm tactics” in the negotiations pertaining to telecommunication patent licensing.

Apple filed the lawsuit on Friday in the U.S. District Court for the Eastern District of Texas. It alleges that Ericsson has been using ‘strong-arm tactics’ in negotiations to renew a 2015 license for technology critical to telecommunications standards, and for 5G mobile networks in particular. The latest iPhone models are reported to use the aforementioned technology.

The lawsuit further accuses Ericsson of making unreasonable demands and “violating its obligations to license patents essential to industry standards on fair rates.” It is reported that Apple has brought two motions. One motion seeks to dismiss Ericsson’s complaint, the second motion seeks to seal the complaint as it contains “sensitive information relating to business operations.”

This appears to be in response to Ericsson filing its own lawsuit against Apple, in October this year, accusing the latter of negotiating in “bad faith.” It sought declaratory judgment to prove that it is ready to deal under fair, reasonable, and non-discriminatory (FRAND) terms.

This licensing dispute between the two companies has been going on for nearly seven years. The licensing negotiation began in 2015, with Apple dragging Ericsson to court over excessive royalty fees for its LTE patents. The Swedish company was quick to counter the iPhone maker with its own complaint stating that Apple’s licenses to use its technology used in smartphones, tablets and more had expired. Ericsson even went so far as to seek a ban on iPhone sales in the U.S. Ultimately, Apple agreed to pay Ericsson royalty fees for every iPhone and iPad sold for the next seven years.

This agreement, however, is due to expire this month, and with it, you can expect to see a host of infringement filings popping up. It is reported that Apple has a couple of powerful attorneys in its arsenal to handle its litigations.