Apple is the target of patent infringement suits more often than it would like and it has been sued by a Taiwan firm called Elan Microelectronics. Elan filed suit against Apple for allegedly infringing on two Elan patents that pertain to touch screens.

The New York Times reports that the suit was filed late Tuesday afternoon according to an Elan spokesman named Dennis Liu. Liu told the NYT, "We couldn't find a common viewpoint with Apple, so we decided we had to take action,” he said, adding that the companies had been in licensing talks for about two years."

Products allegedly infringing on Elan patents produced by Apple include the MacBook, iPhone, and iPod touch with Elan specifically stating that the products infringe on to multi-touch patents it holds. Exactly what Elan hopes to gain from the suit isn't unknown; the court filings don’t specify if the company wants monetary damages or injunctive relief.

What is known is that the three products that allegedly infringe on the patents held by Elan are responsible for a large portion of Apple's Q4 earnings of $1.61 billion reports the NYT. During Q4 Apple moved 4.4 million iPhones. Apple would not comment on the suit.

Elan is emboldened by the fact that it recently won a preliminary injunction in a patent dispute with Synaptics in a dispute over one of the same patents in the Apple suit. The case against Synaptics settled out of court when the two firms agreed to a licensing deal with unspecified terms.

Analyst Jessica Chang from Credit Suisse told the NYT, "From their previous victory in the case with Synaptics, I think they [Elan] should be quite confident. Elan believes they have a unique edge with this patent, and they want to send a signal to the market."

This likely isn't the last touch screen patent suit that will be seen -- touch screens are becoming increasingly common all sorts of device types.