In 2002, a startup named SawStop demonstrated a table saw that could miraculously cut through wood, but stop itself dead (video below) as soon as its spinning blade touched skin. The mechanism was incredibly effective, heading off some 2,000 of the nearly 300,000 table-saw-related emergency room visits that occurred in the US since the company sold its first saw. But despite SawStop’s effectiveness, the big tool companies still haven’t added it to their products. Meanwhile, saw-related injuries result in some $2.3 billion in medical bills, lost wages, and other societal costs every year. Fair Warning investigates why the power tool industry has so far failed to license the SawStop technology or implement its own alternative. "If the manufacturers had to pay the cost of those injuries," says inventor Stephen Gass, "they would have adopted technology like this within months of the time they heard about it."