The California Supreme Court decision in Ixchel has left some uncertainty regarding whether business to business employee nonsolicitation provisions will be evaluated under the rule of reason, or deemed a per se violation of California Business and Professions Code Section 16600. See Ixchel Pharma v. Biogen, 9 Cal. 5th 1130, 1158 (2020); Edwards v. Arthur Andersen, 44 Cal.4th 937, 946 (2008).

Under Section 16600, "every contract by which anyone is restrained from engaging in a lawful profession, trade or business of any kind is to that extent void" unless the restraint falls within a statutory exception. When applying Section 16600 to a contractual restraint and in absence of a statutory exception, courts may now either invalidate the restriction under Edwards, without inquiring into the restraint's reasonableness, or evaluate whether the provision is unreasonable pursuant to a "rule of reason" test. Cf. Ixchel, 9 Cal. 5th 1130 with Edwards, 44 Cal.4th 937, 946 (2008)