I think the high concentration of tech jobs and employee-favorable IP ownership legislation are a great combination for the states you mention. Causality could

I think the high concentration of tech jobs and employee-favorable IP ownership legislation are a great combination for the states you mention. Causality could easily work either way here though. CA, WA, and NC are some of the only states with enough tech companies and tech employees to care about this stuff. Software has a much more favorable cost structure than most industries; employees can easily fully implement their ideas on their own time and their own dime. So it makes sense that these issues have come up enough often enough in the legal system, or tech companies/employees have lobbied hard enough, to fully flesh out the legislation on the matter in these states.