Federal appeals court upholds Nintendo's win in 3DS patent battle

The Nintendo 3DS doesn't infringe on Tomita's display patent.

Just months after the Nintendo 3DS launched in 2011, it faced patent infringement allegations. Tomita Technologies was accusing Nintendo's new handheld of using its glasses-free 3D display technology without paying royalties. Like most patent lawsuits, it dragged on for years -- first awarding a victory to Tomita before handing the win to Nintendo in appeals. Now, a higher court has confirmed Nintendo's victory. On Friday, the Federal Circuit court ruled that the Nintendo 3DS does not infringe Tomita's patent.

The question at hand was never if the 3DS allowed for glasses-free stereoscopic images, but rather how it joined the two perspectives of a 3D image to create the illusion of depth. The court used two tests to sort this out -- one that tested to see if the function itself was similar, and a second to determine if the differences between the methods were substantial. "Under both tests," the court wrote in the ruling, "the district court found that the 3DS and the disputed limitation do not possess equivalent structures."

In other words, the 3DS still offsets two images to create a 3D illusion, but not in a substantially similar way as Tomita's old patent. It's a big win for Nintendo, who would have had to pay $15.1 million in damages if its past victory had not been upheld.