Ares Armor gets temporary restraining order against BATF
Summary here. Essentially, Ares makes "80% receivers." A receiver starts out as raw material -- steel, or here polymer. Everyone can agree that's not a receiver. At the end, it is a finished receiver that, with the appropriate parts attached, can fire. We can all agree that that is a receiver. But at what point between the two does it go from being in one legal status to being in the other?
The industry understanding (and I emphasize understanding) has been that the line is crossed when the future receiver is 80% complete. But this is one area where BATF rulings, if any, are kept private, and never published as a regulation. This violates the Administrative Procedure Act (which requires that general rules for the public be published as regulations -- you cannot have a rule that the public must comply with, and keep it secret) and allows a little of wiggle room for "our position is" or "our position has always been."
Hat tip to Jeff Harris....