Impinj Can’t Lean on Two of Its Chips in Push to Nix NXP Patent

Impinj Inc. won’t be allowed to add two of its own chips to its invalidity contentions as to one patent in NXP Semiconductors NV’s suit over integrated circuits using radio frequency identification tags that are increasingly used by businesses to wirelessly connect products to the Internet.

The court’s construction of disputed terms in the NXP USA Inc. patent “does not justify Impinj’s late attempt to amend its invalidity contentions,” Judge John H. Chun wrote in an opinion issued Tuesday in the US District Court for the Western District of Washington.

“Impinj has been aware of this prior art throughout the ...