Rival headphones manufacturer Bose is suing Beats by Dre for alleged copyright infringement, according to multiple sources. The lawsuit claims that Beats has infringed on five patents relating to active noise reduction (ANR) — its noise-cancelling technology.
 
“ANR is a technique to reduce unwanted noise by introducing a second sound source that destructively interferes with the unwanted noise,” explained Bose’s lawyer in documents filed with Delaware District Court.
 
The lawsuit comes two months after Apple announced it was buying Beats for $3 billion.
 
According to court documents, Bose was granted the rights to the inventions over a nine-year period ranging from 2004 to 2013. BBC News writes that “the company originally developed the technology for the US Air Force and US Army, before launching its first noise-cancelling headphones for consumers in 2000.”
 
Other headphone makers such as JVC, Sennheiser, and Sony use a similar feature but Bose’s director of public relations Carolyn Cinotti told BBC that “we don’t license our technology to other headphone manufacturers.”
 
Related: Beats by Dre President Defends Headphone Quality

The quality of Beats by Dre’s ubiquitous headphones is a contentious topic in the DJ and producer communities. While there’s plenty of high-profile artists that can be seen sporting the headphones on a regular basis, others claim they lack quality.
 
During a recent visit to the UK, Beats president Luke Wood spoke exclusively with BBC Newsbeat to respond to comments that the headphones are too bass heavy:
 
“We didn’t go to build a reference headphone, something you build in the studio that is really a technical tool to hear when you are recording.”
 
He added, “If you look at Dre’s pedigree, Jimmy’s [Beats co-founder Jimmy Iovine] pedigree, even my pedigree, we are all recording engineers.”
 

“What we did is build a headphone for playback. What does it sound like right when it is finished? And that is what we’ve accomplished.”

 
Wood also addressed rumors about the sockets on Apple products being changed to only take Beats by Dre headphones and what it’s like working with Dr. Dre:
 

“Having a chance to meet him, I can honestly say the only other artist that I feel the same way, that I have been fortunate to meet, is George Harrison.”

 
Read the full interview here.
 
Related: Beats by Dre Headphones Banned at World Cup

Beats by Dre’s headphones have been banned from the 2014 World Cup due to a licensing agreement between FIFA (the championship’s organizer) and Beats’ rival, Sony Electronics.

Soccer players are required to take off Beats headphones when they’re in World Cup stadiums for official matches and media events. Ironically, many of the sport’s biggest stars are fans of the company’s ubiquitous headphones and have been seen using them on a regular basis.

Some of the players were even featured in a recent short-film produced by Beats which has been seen by over 15 million people on YouTube.

Could the ban actually help strengthen Beats’ brand though? Former Apple and Google executive Ellen Petry told Reuters that it’s a possibility:

“When fans see World Cup athletes wearing Beats in their downtime, by choice, it has as much impact as seeing them lace their Adidas (boots) or sip a sponsored beverage. Maybe more, actually — Beats isn’t a sponsor, so the message is more authentic and credible.”

Related: Apple Confirms Purchase of Beats for $3 Billion