​Oura sues Circular as smart rings go to war

The first battle of the smart ring era
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Smart ring company Oura has launched a lawsuit against newcomer Circular, alleging an infringement on two of its patents.

Oura is the incumbent of the smart ring world, with its excellent health tracking Oura 3. But Circular is set to bring its first smart ring to market, which opened for pre-orders back in April, and shipping set for August 2022.

The Circular Smart Ring tracks biometrics, sleep, energy levels and supposedly helps you monitor wellness and your immune system. It also goes deep, with metrics on blood oxygen, VO2 Max, resting heart rate and recovery.

But Finland-based Oura Health Oy has filed a complaint in the Western District of Texas against Circular SAS claiming that it’s infringed on two patents.

Patent “833” refers to the design of a smart ring, having inner and outer surfaces, and the electronic components contained within a cavity, housed within a non-ceramic coating.

The second “429” patent refers to the measurement of biometrics, specifically the energy score generated by Circular. Oura alleges the way that the score is collected, by analysing data at rest, infringes on its patent.

"The ’429 Patent' generally describes and claims a method and system of obtaining a user’s movements, using the movements to determine a rest period or activity period, measuring biosignals during the rest period," states the filing.

These are certainly broad stroke patents, but they have been granted by the US Patent Office. It's hard to see how the '429' patent differs from most other wearables that track user vitals at rest – but that will be for lawyers smarter than us to prove.

Update: An Oura spokesperson reached out to tell us:

"At Oura, we embrace creativity and innovation in health technology, including from our competitors. However, what we cannot accept is direct copying, as this does nothing to help consumers or advance our industry. The lawsuit filed against Circular addresses willful infringement of at least two Oura patents."

The claim states that Oura filed a cease and desist in January 2022, and that Circular acknowledged the complaint and hired lawyers to study the patents.

“Our goal is to achieve innovation for the greater good and a monopoly situation has never driven innovation," read a statement from a Circular spokesperson.

The smart ring market is certainly a nascent but growing space, and we saw litigation emerge in the early days of the fitness tracker between Jawbone and Fitbit, with the latter alleging broad trade secret theft. The court eventually found no evidence of wrongdoing.

It will certainly be interesting to see how this plays out.

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James Stables


James is the co-founder of Wareable, and he has been a technology journalist for 15 years.

He started his career at Future Publishing, James became the features editor of T3 Magazine and T3.com and was a regular contributor to TechRadar – before leaving Future Publishing to found Wareable in 2014.

James has been at the helm of Wareable since 2014 and has become one of the leading experts in wearable technologies globally. He has reviewed, tested, and covered pretty much every wearable on the market, and is passionate about the evolving industry, and wearables helping people achieve healthier and happier lives.

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