"The linking of Amazon's house mark with the 'Fire TV' name is an aggravation of the likelihood of confusion, increasing the possibility that WREAL' s product could be seen as an imitator of Amazon's dedicated [set-top box]," the company said in its complaint. "Such a result is unacceptable because WREAL was the first (by many years) to use the trademarks FyreTV and FyreTV.com in connection with its dedicated STB and streaming on-demand content over the internet."

Amazon did not reply to multiple requests for comment.

While FyreTV is limited to adult content, WREAL says it has always been the company's intention to broaden its offerings.

"Indeed, the underlying technology that powers FyreTV is a flexible and scalable platform capable of delivering content to a wide variety of internet media streaming devices. In that regard, WREAL has plans to use the FyreTV brand to expand its content," the filing said.

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The suit alleges Amazon did not do due diligence in choosing the name, noting that had the company simply typed in firetv.com, it would have been taken to WREAL's website, which markets its product.

However, the Firetv.com website notes that the Fyre Boxxx is sold only in specific markets around the globe but is no longer available to U.S. residents. In fact, at the time of the Amazon Fire TV launch, WREAL made no mention of its set-top box on its website. (Cached copies of the site indicate it restarted promotions for the hardware on April 5—after media reports on the name similarities had become widespread.)

Before Amazon's announcement, Fyre TV had not updated its Twitter feed since August and it had not made any corporate announcements for years. Many insiders in the porn world thought the company had folded long ago.

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While Amazon's Fire TV and FyreTV spell their names differently, WREAL apparently bought the firetv.com domain expecting people to misspell its name. Subscribers are able to stream explicit XXX content directly to their TVs via Roku and other third party set-top boxes as well as WREAL's own player.

Regardless of its state today, FyreTV was one of the forerunners in bringing streaming adult entertainment to the living room. Earlier this year, another service—SkweezMe—launched a video- on-demand service that closely follows the iTunes model. MindGeek (formerly called Manwin), the porn industry's largest company, plans to unveil a similar venture later this year.