Xiaomi and Huawei Technologies have become embroiled in a rare public spat over a foldable phone patent, a sign of intensified competition in China’s smartphone market.

The dispute originated last Saturday when Huawei’s chief executive of consumer products, Richard Yu Chengdong, said “some competitors took our intellectual property and renamed it as their own”, without naming any company.

Yu, who was speaking to a group of Huawei users at an event in Dongguan, Guangdong province, specifically mentioned Xiaomi’s refined “keel hinge” design, used in its foldable phone, saying that the design was a copy of Huawei’s dual-track, wing-shaped hinge used on the Mate X3, X4 and X5 models.

Xiaomi refuted Yu’s comments on Tuesday, issuing a statement saying they were “completely out of line with facts”.

Yu’s statements amounted to “defaming a rival and misleading the public”, according to a statement published on one of Xiaomi’s official Weibo accounts.

Xiaomi said its three-element hinge was patented in January 2021, five months before Huawei’s two-track design was approved by the China National Intellectual Property Administration. Huawei applied for a patent on a hinge with three tracks in October 2021.

Huawei did not immediately respond to a request for comment on Tuesday.

The controversy comes at a time when competition for foldable phones is heating up. The market is expected to triple by 2027, accounting for 50 million units annually, according to a forecast by electronics industry consultancy IDC.

While foldable phones make up only 1% of smartphone shipments, according to estimates by IDC, Neil Mawston, the director of research for Strategy Analytics, said they would account for 5% of total smartphone wholesale revenues this year because they are usually priced higher.

The number of foldable smartphones on the market has increased since South Korean giant Samsung Electronics jumpstarted the category with its Galaxy Fold in 2019. Companies including Motorola, Xiaomi, Huawei and Oppo have all unveiled their own foldable models since then.

Google joined the race this year, introducing the US$1,799 Pixel Fold in May, which comes with a 7.6in main display and a 5.8in external panel.

Companies have been undertaking efforts to reduce the size of the “crease” on the screen of foldable phones, with hardware and engineering limitations contributing to the challenge.

Xiaomi chief executive Lei Jun said its new-generation hinge helps improve durability, with the crease increasing by only 10 microns after 200,000 folds.

Vivo, another major Chinese phone brand that launched the Vivo X Fold 2 and Vivo X Flip in May, used a combination of flexible glass and adhesive so the crease would reduce in size as it was used.

Samsung’s latest Galaxy Z Fold 5, also launched in May, featured a teardrop-shaped hinge that facilitates a less noticeable crease.

Huawei’s foldable model, the Mate X5, sold out soon after release in September, according to analysts. The model featured the same 7-nanometre system-on-a-chip processor as the Mate 60 Pro series, which created huge consumer interest when it was released because it proved that Huawei could make an advanced 5G smartphone despite US tech sanctions.

 - SCMP