In the January 23, 2004 Federal Register (69 FR 3434), the U.S. Department of Health and Human Services (HHS) published a final rule establishing the standard for a unique health identifier for health care providers for use in the health care system and adopting the National Provider Identifier (NPI) as that standard (“2004 NPI final rule”). The rule also established the implementation specifications for obtaining and using the NPI. Since that time, pharmacies have encountered situations where they need to include the NPI of a prescribing health care provider in a pharmacy claim, but where the prescribing health care provider has been a noncovered health care provider who did not have an NPI because he or she was not required to obtain one. This situation has become particularly problematic in the Medicare Part D program. The addition to the NPI requirements addresses this issue.