On December 21, 2022, ATF issued an open letter to all FFLs regarding the application of Final Rule 2021-05F, “Definition of ‘Frame or Receiver’ and Identification of Firearms”, on partially complete Polymer80, Lone Wolf, and similar semiautomatic pistol frames.

Below is the message from ATF:

In April 2022, the Department of Justice announced a new “Frame or Receiver” final rule, which modernizes the definition of a firearm. The final rule, which went into effect in August 2022, clarifies that parts kits that are readily convertible to firearms are subject to the same regulations as firearms made by a federal firearms licensed manufacturer. Today’s open letter clarifies to the firearm industry and the public how the August 2022 final rule addresses partially complete, disassembled or nonfunctional semiautomatic striker-fired pistol frames or parts kits manufactured, sold or distributed by Polymer80, Lone Wolf and others.

Partially complete Polymer80, Lone Wolf, and similar striker-fired semiautomatic pistol frames, including, but not limited to, those sold within parts kits, are regulated by the Gun Control Act (GCA) because they have reached a stage of manufacture where they “may readily be completed, assembled, restored, or otherwise converted” to a functional frame.

This definition of “readily” applies to each classification of a partially complete frame or receiver under this rule, whether sold alone or as part of a kit; therefore, even without any associated templates, jigs, molds, equipment, tools, instructions, guides, or marketing materials, these partially complete pistol frames are “frames” and “firearms” as defined in the GCA and its implementing regulations.

If anyone remains unclear about a specific model or configuration, they may submit a request with a sample to ATF, who can only render a formal determination upon receipt of a formal request and physically examining a submitted sample. Please contact FIPB@atf.gov for questions.

The published open letter can be read and downloaded here.