A lawsuit alleges a Bose app secretly collects and shares everything its headphone users listen to

An Illinois man is suing headphone giant Bose for allegedly collecting and sharing its users' listening data in secret.

Fortune first reported on the lawsuit.

A man named Kyle Zak filed the complaint in federal court in Chicago on Tuesday night. At the center of the lawsuit is Bose's Connect app, which is marketed as an optional companion to a handful of the headphone maker's newer headphones and speakers, including its acclaimed QuietComfort 35 noise-cancelling headphones.

Bose says the Connect app is meant to adjust noise-cancellation, more quickly manage connected audio devices, and view other settings.

But Zak and Chicago-based law firm Edelson PC, which specializes in cases involving technology and consumer privacy, claim the Connect app also "intercepted and collected all available Media Information" from Zak's smartphone, every time it was opened, after Zak paired the app with his pair of QuietComfort 35s.

Zak alleges that Bose collected the titles and general info for every song, podcast, or other audio file he listened to when paired with the app, then transmitted that data to "third parties." The lawsuit specifically mentions Segment, a Bay Area software company that collects customer data and helps route it for analytics and marketing firms, as one alleged recipient of the information claimed to be taken by the Connect app.

The lawsuit alleges that Bose did not inform Zak that it would collect and share such data. The Connect app's latest license agreement does note that it "may collect, transmit, and store" various pieces of customer data to "servers operated by third parties on behalf of Bose," but does not specifically mention collection of audio file data.

The app's privacy policy gets a little more specific, noting that Bose "may partner with certain third parties" to collect "non-personal information" and "to engage in analysis, auditing, research, and reporting." Bose specifically mentions Segment in the policy as of this writing, and says partnering with such companies allows it to "better control data from the app and direct it to third-party analytics providers."

The privacy policy does not describe how Bose collects that data, though, nor does it specify if a user's listening data counts as "non-personal" information.

The lawsuit says that tracking a user's listening habits could enable Bose to create "detailed profiles" of its users, since it can collect their names and email addresses during signup, and tie that information to a product's serial number as well.

"For example, a person that listens to Muslim prayer services through his headphones or speakers is very likely a Muslim, a person that listens to the 'Ashamed, Confused, And In the Closet Podcast' is very likely a homosexual in need of a support system, and a person that listens to 'The Body's HIV/AIDS Podcast' is very likely an individual that has been diagnosed and is living with HIV or AIDS," the lawsuit reads.

The lawsuit says the "amount in controversy" exceeds $5 million, but does not give an exact amount it is seeking in damages. If the complaint is certified as a class action, it would apply to all users who may have had their data collected by the Connect app. Zak is seeking to end the alleged collection altogether by saying it violates the federal Wiretap Act, along with a variety of Illinois state privacy laws.

Neither Bose nor Segment responded to requests for comment.

The lawsuit does not note how Zak found the Connect app to be collecting such data, nor does it provide any proof related to how much data Bose provides to Segment. 

Christopher Dore, an Edelson lawyer representing Zak, told Business Insider that the law firm had "computer forensics experts" look into and discover the matter. Dore said Bose is the first headphone company Edelson has found to collect such data. He also said the firm did not reach out to Bose or Edelson before the lawsuit.

The lawsuit is just the latest in a string privacy-related legal complaints have had in an increasingly connected tech landscape. Those concerns may only intensify when it comes to headphones, a market that's expected to integrate more and more "smart" data processing features in the coming years.

The lawsuit also comes a month after another lawsuit accused Bose of duplicitous business practices with California headphone startup Doppler Labs.

Bose, a privately held company, had annual revenues of $3.5 billion in 2015 according to Forbes.

You can see the full complaint below: