Apple Inc. will again be forced to stop selling its smartwatch devices fitted with blood oxygen sensors, following a ruling today by the U.S. Court of Appeals for the Federal Circuit.

The court did not rule on Apple’s bid to overturn a U.S. International Trade Commission ban on selling its smartwatches in the U.S., but instead lifted an injunction that allowed Apple to continue selling the products while its appeal is pending.

The ban was implemented after the ITC ruled in favor of a medical device company called Masimo Corp., which alleged that Apple’s blood oxygen sensors infringed on its intellectual property. Apple’s Watch Series 9 and Watch Ultra 2 wearables can measure the wearer’s oxygen levels using a sensing technique known as pulse oximetry. According to Masimo, Apple rejected an offer to use its pulse oximetry technology, but went on to poach about a dozen of its employees in order to recreate its own version of that tech.

The ITC ruling in favor of Masimo is what led to the original ban on sales of Apple’s devices. Apple was officially told to stop importing any Apple Watch models that violated Masimo’s patents on Oct. 26 last year, though that order would only come into effect after 60 days.

On December 18, Apple said it would stop selling the affected products in the U.S. Online sales were promptly halted on Dec. 21, while sales in Apple’s physical stores were shut down on Dec. 24.

Apple did try to stop the ban by filing a motion for a stay of execution, but that was denied on Dec. 20. However, the company then turned to the appeals court, and on Dec. 27 it managed to persuade judges to delay the ban while they deliberated its request.

Now, though, the devices are once again banned from being sold, as the Court of Appeals denied Apple’s request to continue selling them until the ITC hears its appeal. Court documents show that Apple’s interim stay will be lifted as of Jan. 18.

The ruling only affects Apple’s own stores, which means that third-party retailers can continue to sell the affected Apple watches, though they will be able to do so only until their stocks last.

Apple appears to have been bracing itself for the ruling. Earlier this week, Bloomberg reported that the company has received approval from U.S. Customs to import modified versions of the Watch Series 9 and Watch Ultra 2 that do not have the blood oxygen feature, and therefore do not infringe on Masimo’s IP. As such, that would allow Apple to resume selling the devices again.

Image: Apple