So in the USA if you work for a medium-large company they will almost certainly have you on a "self funded health plan". These are plans where the Cigna, Anthem

So in the USA if you work for a medium-large company they will almost certainly have you on a "self funded health plan". These are plans where the Cigna, Anthem, etc. card you get makes it look like that's your insurer, but in actual fact your employer is your ensurer. The Cigna/Anthem/etc. you are interfacing with is just a contracted administrator that handles the billing, claims, etc. processes, then passes the full costs back to the employer. (The employer will also have various re-insurance set ups to limit their total liability in case of very expensive situations.) This administrator (Cigna et al.) will have a bunch of policies for certain treatments and drug uses that define when they can be used. These operate like a firewall rule, being parsed, and if you don't match perfectly, you get denied. Sometimes they'll be more flexible, but some are known to be terrible (cough Cigna cough). If you don't match this policy perfectly then your treatment gets classified as "experimental". At that point they point you to something called the "XYZ Company Handbook" which is something your employer maintained. This is a document that almost never exists in reality, but the gist is that "XYZ Company Handbook" will say experimental treatments are not covered. (There was nothing really experimental about my treatment, it’s just high dose IVIG, with lots of patients on it and a half dozen of my doctors all supporting it. Experimental seems to be their euphemism for “expensive, so we don’t want to cover it”.) So administrator points to employer, then you go to your employer, they point to the administrator. Then you go to a lawyer or your state insurance commission for help, and they say because it's a self funded health plan it is not technically an insurance product, and is regulated under federal law as an ERISA plan. This means years in court, and the maximum you can ever recoup is only the costs of the treatment. So you have to pay for treatment up front, then fight to get those costs reimbursed. And because there can be no punitive penalties there is no real incentive to act in good faith. Your lawyer (or state insurance comission) will also point out that because the plan is self funded your employer is actually the ultimate authority and can approve or deny or make exceptions for any claim. The appeals process can include something called an independent review, where an outside organization can review your case and recommend treatment or not. This is a time consuming process though. Also it doesn't always work out. And they tell you that they are not bound by the results of the IRO anyway. In our case we were able to change from our employer's self funded plan to a legacy brokered plan, an old school type one where your premiums actually go to the insurance company and the insurance company pays for all treatments. These are regulated by state insurance commissions. This plan was actually provided by a not for profit Blue Cross/Blue Shield and they covered the treatment immediately because my case was pretty darn obvious that I needed it.