Apple Brings Back Blood Oxygen by Rerouting Measurements

Apple reroutes Blood Oxygen to iPhone to sidestep ITC import ban

Apple announced a redesigned Blood Oxygen capability for some Watch Series 8, Series 10, and Apple Watch Ultra models that were sold after an early‑2024 import ban. Instead of calculating values on the watch, the device will send raw data to the paired iPhone, where blood oxygen will be measured and calculated and the results shown in the Respiratory section of the Health app.

The change follows a U.S. Customs ruling that allows Apple to import watches with this redesigned workflow. It effectively keeps the sensor hardware in the watch but moves the analysis step off the device — a workaround to a previous International Trade Commission decision that had blocked imports of watches using Apple’s original blood‑oxygen implementation.

That ITC ruling came after medical device maker Masimo accused Apple of infringing its pulse oximetry patents. Masimo won the initial action, triggering the import ban; Apple has counter‑sued and is appealing the decision. The new approach only affects watches sold after the ban took effect and does not alter devices already in users’ hands or units bought outside the U.S.

For users the shift is simple but meaningful: blood oxygen readings will not appear on the watch face itself. Users must open their iPhone to view the calculated readings and historical data in Health. That raises questions about accessibility, latency, and how manufacturers present critical health data when the processing moves off the wearable.

There are broader implications across product, legal, and regulatory teams:

• Manufacturers: reconsider on‑device vs. phone processing when patents or import restrictions threaten supply.
• Developers: ensure telemetric integrity when raw sensor streams are offloaded to a paired phone for computation.
• Health providers and regulators: evaluate clinical equivalence and privacy when calculations move between devices.

Technically, moving computation to an iPhone changes the threat model and the validation surface. Developers must validate that transmission of raw photoplethysmography (PPG) or related signals is robust over intermittent Bluetooth links, that calculations produce clinically consistent outputs, and that Health app storage meets privacy and retention expectations.

From a product standpoint, Apple’s move is a practical workaround that preserves user-facing capability while navigating intellectual property constraints. But it’s not a permanent legal fix: appeals and counterclaims remain active, and future rulings could require further architectural changes.

How organizations should react now:

• Run patent and import‑risk scenarios to understand which features can be retained, redesigned, or deferred.
• Test phone‑based processing end‑to‑end for accuracy, latency, and resilience under real‑world connection conditions.
• Plan user communications and UI changes so critical health signals remain discoverable even if not shown on the watch face.

QuarkyByte’s approach is to map these technical, legal and user‑experience tradeoffs together. We run scenario simulations to estimate supply and compliance impact, prototype alternate data flows to preserve accuracy, and shape rollout plans that reduce user disruption while preserving legal options.

This Apple update is a reminder that hardware innovation often meets legal and regulatory limits; engineers and product teams should expect more architectural workarounds ahead. Watch for how the appeals progress and whether other wearable makers adopt phone‑based calculations as a common pattern.