Or they went about developing their own systems. Bosch made their own system that didn't involve slamming a brake into the blade, but SawStop decided to throw some money around and get an injunction against it.

All the evidence I've found is super cloudy, but early reports indicated Bosch's variant predated SawStop's release.

Luckily SawStop's patents expire in a few years so hopefully we'll see other safety mechanisms similar to SawStop without the downsides and greed.