I recently looked into buying an additional practice. Upon reviewing the books and billing history I discovered long running, greater than 10 years, of insurance fraud, waste, and abuse massively on a daily basis. The hired clinicians did not have NPI numbers, which have been required since 2007, and everything has been billed under one persons NPI over 10-15 years. There was only one insurance credentialed provider in the whole facility. Without an NPI number treating and billing are illegal and can also be a violation of HIPAA. First question is do I have to report or just walk away?. If I did buy the business and changed into our practice would I be responsible for their past illegal billing practices? It is a private practice setting