Finnish-US startup has sold 5.5m rings worldwide since it was founded in 2013 and is valued at $11bn Finnish-US startup has sold 5.5m rings worldwide since it was founded in 2013 and is valued at $11bn Stylish Finnish-American smart ring company Oura may be the darling of wearables, adorning the fingers of celebrities and sportspeople, but it is not resting on its laurels as it heads towards an IPO later this year. This week it launched the world’s smallest smart ring, the Ring 5, its latest