Fujitsu Ltd. v. Netgear Inc., 620 F.3d 1321 (Fed. Cir. 2010), was a patent infringement case centered on three patents claimed to be required for full compliance of the IEEE 802.11 (WiFi) standard and the WiFi Alliance Wireless Multimedia Extensions (WMM) Specification. US patents 4,975,952, 6,018,642, and 6,469,993 were owned by Philips Electronics, Fujitsu, and LG Electronics respectively, and placed in the Via Licensing pool. The Via Licensing pool claimed to hold all patents required for a complete WiFi/WMM implementation. Netgear did not enter an agreement with Via Licensing but produced a series of products that conform to the WiFi standard and WMM Specification. Philips Electronics, Fujitsu, and LG Electronics sued Netgear for patent infringement claiming a complete implementation of the WiFi standard implied violating patents held by Via Licensing pool. When tried in United States District Court for the Western District of Wisconsin, the court granted summary judgment of non-infringement by Netgear for all three patents thus plaintiffs appealed. The United States Court of Appeals for the Federal Circuit confirmed non-infringement for two of the three patent and found infringement of the third patent in four of Netgear's products. Background Fujitsu, LG Electronics, and Philips Electronics were participating in the Via licensing pool and hold US patents 6,018,642, 6,469,993 and 4.974,952 respectively that were claimed to be required for complete implementation of the IEEE 802.11 (WiFi) standard and the WiFi Alliance Wireless Multi-Media (WMM) Specification. Via licensing Pool sent letters several times from 2005 to 2007 to Netgear noticing that its products that were compliant with the 802.11 standard had infringed patents included in the licensing pool. However, Netgear's request that Via Licensing Pool inform specifically which of its products infringed which portions of those patents was ignored and Netgear didn't accept its suggestion on licensing. On December 17, 2007, Plaintiffs sued Netgear for patent infringement and Netgear did seek summary judgment for noninfringement Specific issue in this case Standard patent Plaintiffs' suit was based upon the theory that "networks conforming with IEEE standard also conformed to the patent in suit". Stated simply, plaintiffs attempted to prove infringement by Netgear's products by showing that those products that practice WiFi standard and WMM Specification necessarily infringe three patents in suit. The district court pointed out that the central issue here is whether mere implementation of WiFi standard by Netgear's products made Netgear automatically liable for infringement of patents placed in