Sound system company Bose, filed a lawsuit on Friday at the District Court in Delaware over an alleged patent infringement involving noise-canceling technology in the U.S. that is being used in Beats headphones.

“The filing is comprehensive and explains our position, and as a matter of practice, we don’t comment on ongoing litigation. We can share that for over 30 years, Bose has made significant investments in the research, development, engineering and design of the proprietary technologies found in our headphones,” said Bose in a statement, adding that they are committed to protecting their investment.

Bose also filed a complaint at the International Trade Commission in an attempt to stop Beats from importing its headphones into the U.S. from China.

Apple announced in May that they had agreed to buy Beats Electronics and Beats Music for a whopping $3 billion, although this acquisition has reportedly not yet been completed. Some analysts suggest that the patent infringement case may affect the acquisition deal. In the event of the completion of the acquisition, it will be Apple who has to face Bose in court over the infringements. This is on top of any other legal battles Apple has with companies like Samsung and Google.

This is not the first time Beats has been in court. Earlier this month, Beats pursued complaints against Chinese knock-offs of their headphones, saying that websites based in China were using Beats’ trademarks to make inexpensive, fake versions of the Beats headphones.

In May, MOG founder David Hyman also sued Beats, claiming that they fired him before having cashed in on the 25 percent equity grant that was promised to him.