A federal judge has ruled invalid part of a patent for powering Ethernet devices that Network-1 Security Solutions Inc. has asserted against several
network technology companies, including Cisco Systems Inc. and Netgear Inc. Judge Leonard Davis of the U.S. District Court for the Eastern District of Texas on Tuesday largely upheld his original 2006 claims construction for the patent as part of a previous Network-1 case against D-Link Corp.

The judge also ruled on the defendants’ partial summary judgment motion, which claimed that the first two claims of the patent were invalid because the term “control means” was indefinite and that the ninth claim containing the term “continuing to sense voltage level” was invalid for indefiniteness. Read more