As the first anniversary of Prince’s unexpected death approaches, a lawsuit filed on Tuesday by his estate aims to block the release of a new six-song EP credited to the singer.

The previously unreleased Prince music, finished and packaged by the audio engineer George Ian Boxill, a former collaborator, is scheduled to come out digitally on Friday, exactly one year after Prince’s death, with physical copies due in stores on June 2, according to an announcement on Tuesday. The tracks, called the “Deliverance” EP, were recorded between 2006 and 2008; one song, “Deliverance,” is currently available for sale and streaming via iTunes and Apple Music. (The full EP was also made available early as a download, for $6.99 or $19.99 depending on audio quality, at princerogersnelson.com.)

“The songs were written and recorded when Prince was an independent artist, protesting what he saw as an unjust music industry,” the announcement said. “In the spirit of that independence, and in supporting Prince’s opinion of major label contracts, ‘Deliverance’ is being released independently via RMA, a Vancouver, WA, based record company. The majority of all sales of ‘Deliverance’ will benefit Prince’s estate.”

But in a federal lawsuit filed on Tuesday, the Prince estate, which is now being managed by Comerica Bank & Trust and Paisley Park Enterprises, claims that Mr. Boxill has no legal right to release the music and is violating the terms of his agreement with Prince “for his personal gain at expense of the Prince Estate.”