Our OBGYN providers have left our group effective 9/1/08. I am working on the billing for surgeries done in August, where the physician did a preop and surgery in august, while with our group, and the same physican will be doing the post op but billing under a different group practice, nothing to do with us anymore. Any suggestions to bill correctly for only the services he's done while with our group? I first wanted to use the modifier 54 on the surgery, but then realized he won't get credit for the preoperative work. If I bill and E/M for the preop with a 56 (preop care only) I think our carriers will hold a copay and since he did also do the surgery, I don't think that's fair. If I bill global, is that legal, since our group really isn't providing the post operative care, but the provider is. Would it be legal to bill a global, and maybe give a small percentage to the other group? It is a really unique situation where our group practice is a sub group of a hospital. The obgyn department was at our facility, and we bill seperately, they have now moved to a different group practice under the same hopstial but different billing group.