The Department of Justice anticipates issuing a Notice of Proposed Rulemaking (NPRM) that would interpret the statutory definition of “machinegun” in the National Firearms Act of 1934 and Gun Control Act of 1968 to clarify whether certain devices, commonly known as “bump fire” stocks, fall within that definition. Before doing so, the Department and ATF need to gather information and comments from the public and industry regarding the nature and scope of the market for these devices.