Every NFA firearm transfer in the United States is subject to a transfer tax except as the part otherwise provides, and the transferor — not the buyer — must pay it. The rate mirrors the making tax: $200 for each firearm transferred in the case of a machine gun or a destructive device, and $0 for any other firearm transferred. As with making, payment and approval are evidenced by the National Firearms Act stamp the Director affixes or applies to the approved application, in adhesive, electronic, or another designated form.

The mechanism is an application, and it is the transferor who files it. Except as otherwise provided in the subpart, no firearm may be transferred unless Form 4 (5320.4), Application for Tax Paid Transfer and Registration of Firearm, has been filed in duplicate, executed under the penalties of perjury, and APPROVED by the Director — the application asks to transfer the firearm and register it to the transferee in the same act. Where the transferee is not a licensee qualified under this part and is a partnership, company (including an LLC), association, trust, or corporation, the Form 4 information must be furnished for each responsible person of the transferee. An individual transferee carries the same identification burden a maker does: a 2 x 2-inch photograph taken within 1 year before the application, full front view with the head bare, attached to each copy, and two properly completed FBI Forms FD-258 fingerprint cards.

What the approval does is the part worth holding onto. On approving the application the Director affixes the appropriate National Firearms Act stamp, CANCELS it, and returns the original showing approval to the transferor, who may then transfer the firearm to the transferee along with that approved application. The approval effectuates registration of the firearm to the transferee — and until it issues, the transferee shall not take possession. The transferee then retains the approved Form 4 as proof that the firearm is registered to them, and must make it available to any ATF officer on request. A transfer under this part is therefore an APPROVAL EVENT that a sale accompanies, not a sale that paperwork follows.

The subpart provides for exemptions, and one of them matters commercially. A firearm registered to a person qualified under this part as an importer, manufacturer, or dealer may be transferred to any OTHER person so qualified without payment of the transfer tax. The exemption is not automatic: the transferor obtains it by filing Form 3 (Firearms), Application for Tax-exempt Transfer of Firearm and Registration to Special (Occupational) Taxpayer, in duplicate and under the penalties of perjury, identifying both parties, their federal firearms licenses and special tax stamps, and the firearm itself. Trade between qualified licensees therefore moves on Form 3, while a taxed transfer moves on Form 4 — those are the two routes this section covers, not the whole of what the subpart provides for.