California Code, Health and Safety Code - HSC § 1389.3

No health care service plan shall engage in the practice of postclaims underwriting. For purposes of this section, “postclaims underwriting” means the rescinding, canceling, or limiting of a plan contract due to the plan's failure to complete medical underwriting and resolve all reasonable questions arising from written information submitted on or with an application before issuing the plan contract. This section shall not limit a plan's remedies described in subdivision (a) of Section 1389.21.