Oura's IPO Filing Puts $84.4 Million on the Ring 4 Battery Problem

Industry News

Quick Verdict

Oura owners have been comparing notes about Ring 4 batteries that fall off a cliff for well over a year, and Oura has never quantified it. The S-1 the company filed with the SEC on September 3, 2026 does. In the section explaining why fiscal 2025 cost of revenue jumped, the filing states that cost of revenue "also increased due to an $84.4 million increase in warranty expense, driven by elevated warranty reserves related to battery performance issues affecting certain cohorts of Oura Ring 4 devices." That is not a forum thread or a leak. It is an audited disclosure Oura has to stand behind, and it is big enough to be visible in the company's margins: gross margin fell from 65% in fiscal 2024 to 52% in fiscal 2025.

Now the catch, because the filing gives you the cost without giving you the exposure. Nowhere does Oura say how many rings were affected, which production runs, which sizes, or which purchase dates, and there is no serial number checker. What the filing does give owners is leverage. In its risk factors Oura writes that it has "replaced affected Oura Rings free of charge under our warranty and, in some cases, outside of the warranty period." Oura's published warranty is one year and it explicitly excludes batteries as a consumable part. So the company's own SEC filing describes doing something its warranty page says it does not have to do. If your Ring 4 battery collapsed, that sentence is the most useful thing in a 300 page prospectus.

What the Filing Actually Says

The battery issue turns up in three separate places in the S-1, which is itself informative. Companies do not repeat a hardware defect across the risk factors, the business section and the financial discussion unless the accountants made them.

The risk factor is the most direct. Under a heading about warranty claims, Oura writes: "We generally provide a 30-day right of return for purchases through our direct-to-consumer channel and a one-year limited warranty on Oura Rings, except in jurisdictions where a longer warranty period is required by law." Then, immediately: "For example, certain cohorts of Oura Ring 4 have exhibited battery performance issues, which has resulted in increased warranty claims and warranty-related costs as we have replaced affected Oura Rings free of charge under our warranty and, in some cases, outside of the warranty period."

The financial discussion supplies the number. Alongside a 131% increase in rings sold and higher per unit costs for the Ring 4's titanium build and expanded sensor array, Oura lists the $84.4 million warranty expense increase as its own line of explanation for a cost of revenue that grew 206% in fiscal 2025.

The business section supplies the framing. Oura says gross margins in the nine months to June 30 in both 2026 and 2025 "were impacted by elevated warranty reserves related to battery performance issues affecting certain cohorts of Oura Ring 4 devices," that it "deployed AI-enabled diagnostics and support tools to streamline this warranty resolution," and that it views the impacts "as attributable to backward-looking design, manufacturing and supplier dynamics." That last phrase is the company arguing to investors that the problem is behind it.

The Numbers Around the Number

All figures below are from the S-1 itself. Oura's fiscal year ends September 30, so fiscal 2025 is the twelve months to September 30, 2025 and the third column is the nine months to June 30, 2026.

Look at the fiscal 2025 column as a whole and the battery problem stops being a footnote. Oura more than doubled revenue to $907.9 million and ended the year with net income of $12,000. Twelve thousand dollars. A single warranty line worth $84.4 million is most of the reason a year that looked like a triumph on the top line finished at roughly break even on the bottom.

Is It Over?

Partly, on the evidence in the filing, and the honest answer is that the filing cannot tell you about the ring you would buy today.

Warranty costs in the nine months to June 30, 2026 were still $28.6 million higher than the same period a year earlier, so replacements were still flowing. But gross margin over that stretch expanded from 51% to 55%, which Oura attributes "primarily due to lower warranty rates relative to earlier hardware cohorts and reductions in per-unit manufacturing costs." Lower warranty rates on later cohorts is the closest thing to good news here: the failure rate appears to be falling as the affected production runs age out.

The limit on all of this is timing. The S-1 states that Oura Ring 4 launched on October 15, 2024 and Oura Ring 5 on June 4, 2026, and that the nine month period "include approximately one month of Oura Ring 5 sales." One month of shipments is not enough data to say anything about Ring 5 reliability, and Oura does not claim otherwise. It says only that it continues to monitor product performance and that "there can be no assurance that current or future product generations will not experience similar or other quality issues."

What To Do If You Own a Ring 4

The practical read, in order.

If your Ring 4 went from multi-day battery life to needing a charge every day or two, and it did that fairly suddenly rather than over years, you are describing the pattern Oura has now told the SEC exists in certain cohorts. Contact Oura support and say so plainly. Give the purchase date and describe the change as a sudden drop rather than gradual decline, because that distinction is exactly what separates a defect from the normal degradation the warranty excludes.

If you are outside the one year window, do not assume the door is shut. The filing says out of period replacements have happened. It does not promise them, Oura is not obliged to give you one, and a prospectus is not a support policy. But it is a documented fact you can reference, which is more than Ring 4 owners had a week ago.

If you are inside the window, this is straightforward warranty territory and you should not be paying anything.

One thing not to do: read this as a recall. There has been no recall, no safety notice, and no regulatory action disclosed in the filing. This is a reliability defect in some units that Oura has been quietly absorbing the cost of, which is a meaningfully different thing.

The Warranty Terms, Which Cut Both Ways

Oura's own Warranty FAQs page sets the baseline. New products carry one year of limited warranty coverage from the date of purchase and certified refurbished products carry 90 days, with longer periods where regional law requires them. Coverage is for manufacturing defects under normal use.

The exclusions are where it gets awkward. The page excludes lost or stolen products, "normal wear and tear, such as scratches and dents caused by everyday handling," purchases from unauthorized resellers, and "consumable parts, including batteries."

So Oura's warranty page says batteries are not covered, while Oura's SEC filing says it replaced rings free of charge because of battery performance issues, sometimes after the warranty ran out. Both can be true: a battery that wears down over years is a consumable, and a battery that fails early because of a manufacturing or supplier problem is a defect. The filing is Oura conceding, in the one document where understating a liability is illegal, that some Ring 4 batteries were the second kind.

Does This Change What You Should Buy?

Not dramatically, and we would resist the temptation to turn one line of a prospectus into a verdict on the product.

The case against overreacting: 3.1 million rings sold in nine months, 5.0 million paid members, and roughly 85% weighted-average twelve month member retention, per the filing. People are not fleeing. The affected cohorts are a subset of a device that has been on sale since October 2024, and warranty rates on newer cohorts are lower.

The case for caution: a smart ring is a sealed object with a battery you cannot replace, so battery life is not a spec, it is the lifespan of the product. That makes a battery defect more serious in a ring than in a watch. If you were weighing a discounted Ring 4 against the Ring 5, the discount now has to cover a known reliability question on the older model, and our Ring 5 versus Ring 4 comparison covers what else the extra money buys. If you are shopping across brands rather than generations, Oura Ring 5 versus WHOOP is the wider comparison, and our earlier piece on what the Oura IPO says about the future of wearables covers the strategy the filing now puts numbers behind.

One more thing the filing makes concrete: 20% of Oura's revenue is membership. Buying an Oura Ring is buying a subscription with a ring attached, and a ring that needs replacing mid subscription is a worse deal than the sticker price suggests.

Where Vora Fits

A warranty replacement raises a question that has nothing to do with money: what happens to your history. A new ring is a new piece of hardware, and the value of two years of sleep and readiness data is that it is continuous.

Vora connects to Oura through the Oura Cloud API rather than reading a device directly, so your data lives in your Oura account and flows onward from there. A replacement ring on the same account keeps that pipeline intact. Our integrations page lists exactly which metrics we pull and from where, and which wearable metrics actually sync to Apple Health covers the more common version of this trap, where switching devices quietly ends a data trail.

We are not going to pretend that having a second copy of your data fixes a dead battery. It does not. What it does is make the replacement a hardware event rather than a reset, and if you are on Android and wondering what reads Oura data over there, Oura on Android is the page for that.