CA SB339

Changes Medi-Cal reimbursement for clinical laboratory services from a "shall not exceed" cap to requiring payment at exactly the lowest of: amount billed, charge to general public, 100% of Medicare's lowest maximum allowance, or a rate based on average of lowest amounts paid by other payers and state Medicaid programs

Creates a carve-out for laboratory services related to sexually transmitted infection diagnosis and treatment, effective July 1, 2027 or when funding is appropriated, excluding those services from the fourth pricing metric (average of other payers' rates)

Exempts STI-related laboratory services data from reporting requirements used to calculate reimbursement rates, effective January 1, 2027 or when funding is appropriated

Requires the Department of Health Care Services to publicly release deidentified raw data on laboratory service rates from providers reporting more than 10 tests, including procedure codes, third-party payer rates, and test volumes

Eliminates the existing 10% payment reduction for clinical laboratory services