House Bill 4351 would amend the Third Party Administrator Act. The bill would require that a contract between a carrier or pharmacy benefit manager and a pharmacy not prohibit the pharmacy from disclosing the current selling price of a drug in accordance with section 17757 of the Public Health Code, as it would be amended by HB 4352. Additionally, the bill would prohibit a carrier or pharmacy benefit manager that reimburses a 340B entity for drugs under federal law from reimbursing the 340B entity for pharmacy dispensed drugs or provider-administered drugs at a rate lower than what it pays for the same drug to pharmacies that are not 340B entities or engaging in any other discriminatory practices against 340B entities including adjustment, network exclusions, or interference with patient choice of pharmacy or provider. In addition to adding provisions concerning pharmacies, the bill would define pharmacy benefit managers and carriers as third party administrators for purposes of the act and add or change definitions for other terms used throughout.