Question: I was recently told that we can use no more than four diagnosis codes on an individual Medicare claim. Is this true? New Mexico Subscriber Answer: In the past, Medicare limited you to only four diagnosis codes per Medicare claim, but that limitation doubles for 2007. According to an MLN Matters release, Medicare will process up to eight diagnosis codes for a procedure, effective for claims processed July 1, 2007, and later. You can read more about this change by viewing MLN Matters article MM5441, online at www.cms.hhs.gov/MLNMatters Articles/downloads/MM5441.pdf.