Perhaps someone has an official ruling about this scenario - but here are my thoughts about that - are you going to charge all of your established patients as new the first time you see them under the new tax ID number? The practice I worked for in Dallas was a single physician for a while; she then incorporated as a group (with some NPP's, eventually other physicians) which changed the name of the practice and her TIN. That did not make the patients new.
You could argue the case for new if none of the other physicians ever, ever saw those patients, or if you didn't have a chart already - but my gut instinct says they are not new patients. This is just my opinion - I can't find anything in writing about this scenario. Others are free to disagree or enlighten me! If there's a source, I'd love to know about it.
And another thought - I know of a case where an Endocrinologist in independent practice passed away suddenly. His patients, of course needed new doctors ASAP. Our group of Endocrinologists took on a lot of them; his office staff would send over their medical records; and our doctors would not charge new patient visits in this case, as a courtesy to the patients. It was good for the patients, the insurance, and created goodwill toward the group.
I wish I could be more help - but I just don't have a resource for this particular question.
Sorry,
