There isn't a 'rule' that you'll find that says this - rather, it's actually something of a loophole in the rules. Insurance policies are regulated by state law - each state's insurance commissioner has the authority to govern the policies that are offered within the state, to approve the policies and the premiums can be charged, and to apply regulations including those that govern timely payments, interest, limits on recoupments, etc. The loophole is that self-funded plans are legally not considered insurance policies - no 'policy' is sold to the member, and there is no premium that is based on risk factors. Rather, the employer chooses to fund their own employees' healthcare costs, effectively becoming a sort of 'self-pay' entity. The companies that administer these plans are not acting as an insurance provider, but are simply hired by the employer to administer the benefit by paying the claims directly out of the company's own funds. As such, these payments are not subject to state insurance laws and are outside the jurisdiction of the state insurance commissioner.