A war of words has broken out between Apple and Palm over unspecified legal threats concerning multi-touch technology.
Apple's acting chief executive, Tim Cook, made a number of comments in last week's earnings call about the company's intellectual property and its willingness to defend it in court.
"We like competition as long as they don't rip off our intellectual property. And we're going to go after anybody that does," he said.
"I don't want to talk about any specific company. I'm just making a general statement that we think competition is good. It makes us all better. And we are ready to suit up and go against anyone.
"However, we will not stand for having our intellectual property ripped off. And we will use whatever weapons we have at our disposal. I don't know that I can be any more clear than that."
While Cook refused to be drawn on the target of the remarks, it has widely been interpreted as a warning to Palm over its Pre device, which uses multi-touch controls in a similar way to the iPhone.
Palm appears to believe this to be the case too. "Palm has a long history of innovation that is reflected in our products and robust patent portfolio, and we have long been recognised for our fundamental patents in the mobile space," Palm spokeswoman Lynn Fox told the Digital Daily blog.
"If faced with legal action, we are confident that we have the tools necessary to defend ourselves."
There is considerable doubt that Apple could prove that it created multi-touch technology if it came to court, according to Bill Buxton from Microsoft Research.
Buxton details the history of touch technology on his blog, and points out that it has been in use for years.
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