You may not be looking for an answer on this any more, but here is my 2 cents. An ABN is a Medicare form and is only good for Medicare patients and Medicare services. So, you would not have a non-Medicare sign an ABN for a service, it wouldn't mean anything. However, you will also find that most commercial insurance companies will pay for some services that Medicare denies by LCD, such as wart removal or the removal of benign lesions. If the service is excluded from the specific policy, then it is usually going to be left to patient responsibility. If the clinic or provider is not contracted with the payer, then it remains the patient's responsibility no matter what. If you are contracted, and the contract states that the patient cannot be balance billed for services the payer deems not medically necessary, than you need to check with the payer or the contract to see if they have a waiver process.