'CMS has issued scores of documentation regarding the fact that ordering/referring providers' NPIs must appear on your claims, but has not released one comprehensive document on the subject -- until now. New MLN Matters article SE1011 sums up the regulations and solidifies the timeline of when CMS will institute the edits. Currently, if you submit a claim without the referring/ordering physician's NPI and that information is not in the MAC's system, you will get a warning letter, but effective Jan. 3, 2011, you could face denials. To read the fact sheet, visit www.cms.gov/MLNMattersArticles/downloads/SE1011.pdf.