Significant litigation occurs on "account stated" issues where professional legal or medical services are involved, and the recipient of the services happens not to object in writing to bills allegedly sent and received. Professional services are required to be "reasonable and necessary" in amount by both law and ethical rules, yet these professional creditors often assert that non-objection constitutes agreement to whatever figure was billed. Especially where legal or medical relations are or may be ongoing, arguing that silence constitutes agreement to what might otherwise be an overcharge can be hotly contested by parties. At least in the case of attorney fees, voluminous litigation exists regarding what's reasonable and necessary given the professional services rendered in a particular context, and accounts are rarely "stated" in professional services cases absent facts such as where there has been payment by the alleged debtor without objection, or a final and unappealed court order for the payment of those professional fees.