Question: What is a valid ICD-10 code?CMS response: All claims with the dates of service of October 1, 2015 or later must be submitted with a valid ICD-10 code, ICD-9 codes will no longer be accepted for these dates of service. ICD-10 cm is composed of codes with 3,4,5,6 or 7 characters. Codes with three characters are included in ICD-10 heading of a category codes that may be further subdivided by the use of fourth, fifth, sixth and seventh characters to provide greater specificity. A three-character code is to be used only if it is not further subdivided. While diagnosis coding to the correct level of specificity is the goal for all claims for 12 months after ICD-10 implementation if a valid  ICD-10 code from the right  family is submitted, Medicare will process and not audit valid ICD-10 codes unless such codes fall into the circumstances describe in more detail.