The NLRA did not preempt plaintiff employees’ claims that Google’s (and its emplyment agency’s) policies forbidding employees from disclosing their wages and working conditions to others violated various Labor Code sections giving rise to plaintiff’s PAGA suit. The NLRA did not arguably protect or prohibit the nondisclosure policies insofar as they blocked disclosure to persons other than co-workers. Moreover, California’s strong local interest in workers’ freedom to seek other employment and to combat wage discrimination brought these claims outside the scope of NLRA preemption.