The U.S. Court of Appeals for the Federal Circuit (CAFC) on Tuesday issued a precedential decision in Willis Electric Co. v.

The Federal Circuit affirmed a Minnesota jury’s $42.5 million patent-infringement verdict against Polygroup Ltd., a large manufacturer of artificial, pre-lit Christmas trees.

I grew up in Northern California, where conifers are plentiful and real Christmas trees are the norm. Each year, sipping on hot cocoa, dead-set on heading home with what we deemed the best tree, we’d ...