CMS: Inactive MDs

Question -

Do we have to report payments to MD's if they do not actively practice medicine?

Answer - 

Yes, a reportable doctor is not determined with whether or not they are actively practicing but instead, whether or not they have an active license.

Most doctors will maintain their license even if they are no longer practicing and are reportable if you have spend with them over individual expenditure thresholds or the aggregate spend threshold.