Iowa Code § 515.106
An insurance company organized under this chapter or authorized to do business in this state shall not terminate a contract of an insurance producer who is an independent contractor but who is not an exclusive insurance producer as defined in section 522B.1 without at least one hundred eighty days' notice, except for loss of license, fraud, nonpayment of company premiums that are due and not in dispute by the producer, or the withdrawal of operations in the state by the insurance company. This section does not apply to insurance producers or a business entity whose contract with an insurer authorized to do business in this state contains a written provision expressly reserving to the insurer all right, title, and interest to the ownership or the use of insurance business written by such an insurance producer or business entity.
Iowa Code § 515.106