SpaceX may have stolen the show with its IPO prospectus, but Elon Musk’s aerospace-AI-data center company wasn’t the only notable business to file to go public this week. On Thursday, Finnish smart ring company Oura said that it had confidentially submitted a Form S-1 to the U.S. Securities and Exchange Commission in preparation for an IPO.

Founded in 2015, Oura has emerged as one of the most popular wearable health trackers, setting itself apart from Fitbit, Garmin, and Apple’s watch products with a sleek, unobtrusive ring.

The Oura ring tracks activity, sleep, and daily “readiness,” among other health metrics, and today has customers around the world. At the time of its Series E last September, Oura said it had sold 5.5 million rings to date, a steep jump from the 2.5 million figure it had reported the prior year.

That Series E saw Oura raising $875 million at a valuation of $11 billion, more than double the $5 billion price tag it had earned in a prior round in 2024.

The company recently introduced a proprietary AI model geared toward women’s health in an effort to cater to its growing base of women customers.