While it is not required, the simplest way to help ensure your background check is processed timely and accurately is to provide your social security number with the NFA application.  Without the social security number, FBI-NICS may have to perform additional research to ensure the applicant is not prohibited, thereby delaying the background check response to NFA Division.  For example, without a social security number, FBI-NICS will have to perform additional research to properly identify the applicant when the applicant has the same name as someone else with prohibiting information in the NICS database.