SB 1644 - This act prohibits a health care provider from offering to a general contract entity or entering into a written provider network contract that includes an anti-steering, anti-tiering, gag, or most-favored-nation clause, all of which are defined by the act. Additionally, a provider shall not amend or renew an existing provider network contract so that the contract as amended or renewed adds or retains an anti-steering, anti-tiering, gag, or most-favored-nation clause. Any provision in a provider network contract that includes any of the prohibited clauses shall be void and unenforceable. The remaining provisions in the contract shall remain in effect and are enforceable. A health benefit plan issuer that encourages an enrollee to obtain a health care service from a particular provider or that introduces or modifies a tiered network plan or assigns providers into tiers has a good faith duty to the enrollee or policyholder to engage in conduct for the benefit of the enrollee or policyholder. This act is substantially similar to HB 3088 (2026). TAYLOR MIDDLETON