Using the FMI Manufacturer Code for the eForm 1 when Manufacturing your Own SBR or Silencer
When you use the eForm 1 registration system you might be manufacturing your own silencer or manufacturing an SBR from a non-serialized lower receiver. This means that in on Screen 5a – Line Item of the eForm 1 application you, your NFA gun trust or legal entity will not be listed as a manufacturer. What the ATF recommends to use as the manufacturer in this situation is the FMI, which stands for “Form 1 Registration.” You can view the exact instructions from the ATF below which was taken from their eFormsNews - eForms 101 – 2015 - Volume 2, Issue 1 January 2015.
Identification of the maker or manufacturer of a firearm on Form 1:
If the applicant is creating the firearm (for example, a silencer or finishing an ‘incomplete receiver’ (that is not yet a firearm)), the applicant will be the maker under the NFA and GCA. Thus, when completing the Line Item (Add Firearm) field, click the “By Manufacturer Code’ button and enter the code ‘FMI’. This code stands for ‘Form 1 Registration’ and the entry can continue. If the model or model and caliber field is not found, click on the box next to ‘My item description is not in the list, create new item’ and add the model or caliber. You will be allowed to submit the application into our Pending Research function in which we validate the information submitted. This should be accomplished in two business days.