Well, it's never too late to bill. The question is, will they pay. Many insurance carriers require notification for rehab. Also, they have timely filing limits. If the facility told the patient they would file the claim and that the patient would get reimbursement this could be a problem for them. However, if they didn't tell the patient they would file the claim and they are now doing it as a courtesy, that is different. But the patients should have inquired on if the claim was filed if they were looking for reimbursement. Ultimately it is the patient/insured's responsibility to know their insurance benefits and what is required (for notification and timely filing of claims).