Cal. Health & Safety Code § 1357.52

Except in the case of a late enrollee, or for satisfaction of a preexisting condition clause in the case of initial coverage of an eligible employee, a plan may not exclude any eligible employee or dependent who would otherwise be entitled to health care services on the basis of any of the following: the health status, the medical condition, including both physical and mental illnesses, the claims experience, the medical history, the genetic information, or the disability or evidence of insurability including conditions arising out of acts of domestic violence of that employee or dependent. No plan contract may limit or exclude coverage for a specific eligible employee or dependent by type of illness, treatment, medical condition, or accident, except for preexisting conditions as permitted by Section 1357.06.