The patent dispute between HTC and Apple has escalated again after the Taiwanese manufacturer filed a lawsuit against Apple in the UK.
The suit was filed on Friday in the High Court, although V3 was told that the documents are not being made public at this time.
The move takes the spat global after a preliminary ruling by the International Trade Commission that could see HTC banned from importing devices into the US owing to two patent infringements.
HTC was cagey on its latest move, refusing to divulge any information on the current case, but issuing a robust defence of its position.
"We don't comment on pending litigation. As a leading smartphone innovator, we respect the intellectual property of others and will defend our own intellectual property as needed," a spokesperson said.
V3 contacted Apple for comment but had not received a reply at the time of publication.
Patent expert Florian Mueller wrote in the Foss Patents Blog that Apple will retaliate quickly and is well placed to take the fight to HTC given its experience fighting patent battles in several markets.
"It's obvious that Apple will strike down upon HTC with a vengeance in the UK and possibly several other countries. Apple already has a lot of experience with intercontinental patent litigation," he said.
"Apple and Nokia were suing each other (until they settled) not only in the US but in the UK, Germany and the Netherlands. Apple and Samsung are embroiled in litigation in at least 11 courts in nine countries on four continents."
Mueller noted that HTC clearly will not lie down without a fight, but Apple is a stubborn opponent.
"By filing a lawsuit in Europe, HTC shows its determination to keep fighting. That determination is beyond doubt," he said.
"But no matter in how many countries HTC may file lawsuits against Apple, it won't be able to change anything about Apple's objectives. Apple optimises for product differentiation, not patent licensing revenues."
Apple recently settled its case with Nokia at a cost of €420m plus continued royalties, and is embroiled in a bitter patent dispute with Samsung.
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