Effective May 23, 2008, for professional and institutional providers, the X12 277 Claim Status Response file will contain NPI numbers only. Files received without an NPI prior to May 23, 2008, will contain the first active NPI for the provider in the 277 response file when a provider has multiple NPI numbers credentialed to their provider profile.

For additional information, please refer to CMS’ MLN Matters article MM5726 .