Nintendo of America, Inc. ("Nintendo") faces a new patent infringement lawsuit in the Western District of Washington, regarding the camera lenses included in its Nintendo DSi handheld gaming systems. The lawsuit, filed on May 24, 2011, accuses Nintendo of infringing United States Patent No. 6,888,686, owned by Plaintiffs Milestone Co., Ltd. and Satoshi Do.

Plaintiffs Do and Milestone Co. accuse Nintendo of both directly infringing the '686 patent by "making, using, selling, offering to sell, leasing, importing and/or exporting handheld gaming systems that infringe one or more claims of the '686 patent," and inducing Nintendo's customers to infringe the patent through Nintendo's "sales, advertising, and instructions." The plaintiffs claim that the camera lens system included in the Nintendo DSi "constitutes a material part of the inventions claimed in the '686 patent."

The technology covered by the '686 patent claims "a lens for image pickup" with multiple lenses of particular shapes, materials, refractive powers, and optical lengths. The plaintiffs claim that the camera included in the DSi handheld system incorporates this technology. 

As relief for the alleged acts of infringement, the plaintiffs are requesting to be paid a reasonable royalty for sales of the DSi devices, as well as pre- and post-judgment interest on damages resulting from the infringement. 

Nintendo's DS series is the highest selling handheld gaming platform of all time, having sold over 135 million units since the release of the original DS platform, according to Nintendo's recent financial reports. Approximately 25 million of those units sold were DSi or DSi XL systems. 

Nintendo comes to this case fresh off of a recent win in another patent dispute concerning its video game controller technology, where the U.S. Supreme Court declined late last year to reinstate a $21 million judgment against Nintendo that had been overturned by the U.S. Court of Appeals for the Federal Circuit. In that case, no infringement was found by any products that Nintendo is currently manufacturing. In the meantime however, Nintendo has been a repeated target of patent holders, settling one lawsuit concerning network encryption patents earlier this month, and currently facing a dispute before the International Trade Commission regarding patents related to a fantasy video game, which was filed in March. 

The case is Do et al. v. Nintendo of America Inc., Case No. 2:11-cv-00865, filed in the United States District Court for the Western District of Washington.