It’s no longer possible to buy Apple’s latest flagship smartwatches, the Apple Watch Series 9 and Apple Watch Ultra 2, from the company’s online store. Apple has removed the devices from sale due to a forthcoming import ban imposed by the US International Trade Commission (ITC) that’s due to take full effect on December 26th. Both watches will disappear from Apple’s brick-and-mortar stores after December 24th.

The ban is the result of a patent dispute with medical device maker Masimo. The ITC has ruled that the SpO2 sensor in Apple’s smartwatches infringes upon Masimo’s patents. On Wednesday, the ITC denied Apple’s motion to stay the ban while awaiting an appeal.

Because the patent dispute relates to the SpO2 sensor specifically, Apple can continue to sell its more affordable Apple Watch SE, which does not come equipped with the sensor. The feature debuted on the Apple Watch Series 6 released in 2020 and has appeared in every flagship Apple smartwatch since. Apple has also pulled refurbished versions of two prior watches with SpO2 sensors, the Series 7 and Series 8, from its online store. Two special editions of the Series 9, the Apple Watch Nike and Apple Watch Hermès, have also been pulled.

The ITC ban only applies to Apple’s own sales channels, meaning other retailers like Walmart and Best Buy shouldn’t be affected until their existing supplies run out. The ban also only affects watch sales in the US — other regions aren’t impacted.

It’s unclear how long the ban could be in effect. Bloomberg earlier reported that Apple’s engineers are working to make changes to the software of affected devices to avoid infringing upon Masimo’s patents, changing the way its algorithms measure blood oxygen levels and how they present that data to the wearer. But Masimo says the underlying patents are hardware-related, which might mean software tweaks aren’t enough to resolve the issue. Hardware changes could take at least three months to resolve while Apple produces and ships new watches, Bloomberg notes.

Option three is a settlement with Masimo, which the company’s CEO, Joe Kiani, has said he’s open to. But as of December 19th, Kiani said, “They [Apple] haven’t called.” In a statement issued Monday, Apple spokesperson Nikki Rothberg said the company “strongly disagrees” with the ITC’s ruling and is “pursuing a range of legal and technical options to ensure that Apple Watch is available to customers.”