In a blog post on the official Sonos website entitled 'Protecting What We Invented', Craig Shelburne, Sonos co-founder and general counsel, reveals Sonos has notified D&M Holdings, the financial investment company that owns Denon, that it believes the "manufacture, distribution, and/or sale of the HEOS system infringes a number of Sonos patents related to wireless audio products".
Shelburne goes on to say that Sonos believes the Denon HEOS range makes "little or no effort to differentiate features of functionality" from its own Play speakers: "Beginning with its product name and messaging (which in some instances they have just copied word for word), Denon borrows liberally from virtually all aspects of the Sonos story."
Sonos says it welcomes competition and the wealth of new products in the multi-room audio market, but that it wants rival manufacturers to "come up with new ideas and true innovations". Clearly, Sonos believes that's not the case with the Denon HEOS range.
"As a next step, we will offer to sit down with Denon, explain our views and give them time to modify their products," says the post. "We are not asking for a royalty or other license fee – we just want Denon to build an experience that isn’t copying ours.
In our hands-on review of the HEOS system we did point out some similarities between it and the Sonos family, such as the names of the products and the prices, though there were also some key feature differences, including the way it used your own wireless network rather than a mesh network like Sonos.
The Denon HEOS line-up features the HEOS 3, HEOS 5 and HEOS 7 speakers, plus the HEOS Amp and HEOS Link. There's certainly some similarity to the Play:1, Play:3, Play:5, Connect and Connect:Amp naming structure.
We have asked for a comment from Denon. You can read the full Sonos statement here.