The high court in London Wednesday found HTC did not infringe on Apple Inc's photo management patent while deeming three other Apple patents -- for slide-to-unlock, multi-touch and multilingual keyboard capability -- invalid.

The court ruled that Apple's "multi-touch" patent was invalid partly due to "obviousness over common general knowledge" in a 81-page ruling. Multi-touch refers to the ability to touch a screen with for example two fingers at a time.

"HTC is pleased with the ruling, which provides further confirmation that Apple's claims against HTC are without merit," the company said in a statement.

"We remain disappointed that Apple continues to favour competition in the courtroom over competition in the marketplace."

HTC touts its own brand of smartphones and also makes handsets for a number of leading US companies, including Google's Nexus One.

An Apple spokesman declined to comment on a specific case, but added "we think competition is healthy, but competitors should create their own original technology, not steal ours".

Patent lawsuits are a regular occurrence among technology giants and Wednesday's ruling was among a string of legal defeats for Apple in recent months.

A Dutch court last month ruled that Apple has infringed on a patent held by South Korean rival Samsung and ordered the US firm to pay an unspecified amount of damages.

In April, Motorola scored a victory when a German court found that Apple's iCloud and MobileMe services breached its patents and ordered Apple to pay damages.

The move comes just days after Apple paid $60 million to end a dispute over who could use the iPad name in China.

Shanghai Zhizhen Network Technology Co Ltd patented its Xiao i Robot software in 2004, while Apple's Siri, which made its debut with the release of the iPhone 4S last year, was first developed in 2007.

The Chinese company's version operates in a similar way to Apple's personal assistant and works on the iOS and Android operating systems.

Si Weijiang, a lawyer acting for the Shanghai-based firm, said it had tried to contact Apple two months ago over the alleged infringement but received no response.

"We sent legal notices to Apple in May, but no one contacted us. We filed the lawsuit in late June to the Shanghai number one intermediate people's court," Si told AFP. "Currently the case is now at the court-mediated stage."

"We mainly ask Apple to stop infringing on our patent and cover the court costs, but once the court confirms Apple has infringed on our patent, we will propose compensation," he added.

The company's chairman, Yuan Hui, told the Apple Daily newspaper that the firm had 100 million users in China.

"People feel that China has no innovation, that companies here just copy. But in fact, we are leaders in our field, and we have created our own innovation," Yuan told the paper.

It added that Apple was also facing legal action from another Chinese company for allegedly infringing its "Snow Leopard" trademark.

The High Court of the southern province of Guangdong said on Monday that Apple had paid $60 million to settle a long-running legal battle with Chinese computer maker Shenzhen Proview Technology over the iPad name.

Both Proview, based in the southern city of Shenzhen, and Apple had claimed ownership of the Chinese rights to the "iPad" trademark.

Proview's Taiwanese affiliate registered "iPad" as a trademark in several countries including China as early as 2000 -- years before Apple began selling its hugely successful tablet computer.

Analysts said the Chinese government wanted the matter resolved, wary of the damage a ruling against Apple could do for the foreign business climate in China.

Greater China -- which includes Hong Kong and Taiwan -- has become Apple's fastest-growing region, with revenues second only to the United States.