# Definition of “Frame or Receiver” and Identification of Firearms > Briefs, arguments, decisions, and more. URL: https://www.frixlaw.com/law-library/documents/fr%3A2022-08026 ## Record - **Collection:** Federal Register - **Document type:** Rule - **Published:** April 26, 2022 - **Citation:** 87 FR 24652 ## Text DEPARTMENT OF JUSTICE Bureau of Alcohol, Tobacco, Firearms, and Explosives 27 CFR Parts 447, 478, and 479 [Docket No. 2021R-05F; AG Order No. 5374-2022] RIN 1140-AA54 Definition of “Frame or Receiver” and Identification of Firearms AGENCY: Bureau of Alcohol, Tobacco, Firearms, and Explosives; Department of Justice. ACTION: Final rule. SUMMARY: The Department of Justice (“Department”) is amending Bureau of Alcohol, Tobacco, Firearms, and Explosives (“ATF”) regulations to remove and replace the regulatory definitions of “firearm frame or receiver” and “frame or receiver” because the current regulations fail to capture the full meaning of those terms. The Department is also amending ATF's definitions of “firearm” and “gunsmith” to clarify the meaning of those terms, and to provide definitions of terms such as “complete weapon,” “complete muffler or silencer device,” “multi-piece frame or receiver,” “privately made firearm,” and “readily” for purposes of clarity given advancements in firearms technology. Further, the Department is amending ATF's regulations on marking and recordkeeping that are necessary to implement these new or amended definitions. DATES: This rule is effective August 24, 2022. FOR FURTHER INFORMATION CONTACT: Vivian Chu, Office of Regulatory Affairs, Enforcement Programs and Services, Bureau of Alcohol, Tobacco, Firearms, and Explosives, U.S. Department of Justice, 99 New York Ave. NE, Washington, DC 20226; telephone: (202) 648-7070. SUPPLEMENTARY INFORMATION: I. Executive Summary A. Summary of the Regulatory Action B. Summary of Costs and Benefits II. Background A. ATF's Application of the Definitions to Split Frames and Receivers B. Privately Made Firearms C. Advanced Notice of Proposed Rulemaking on Identification Markings Placed on Firearm Silencers and Firearm Mufflers III. Notice of Proposed Rulemaking A. Definition of “Firearm” B. Definition of “Frame or Receiver” C. Definition of “Readily” D. Definitions of “Complete Weapon” and “Complete Muffler or Silencer Device” E. Definition of “Privately Made Firearm” F. Definition of “Importer's or Manufacturer's Serial Number” G. Definition of “Gunsmith” H. Marking Requirements for Firearms I. Recordkeeping J. Record Retention IV. Analysis of Comments and Department Responses for the Proposed Rule A. Issues Raised in Support of the Rule B. Issues Raised in Opposition to the Rule V. Final Rule A. Definition of “Firearm” B. Definition of “Frame or Receiver” C. Definition of “Readily” D. Definitions of “Complete Weapon” and “Complete Muffler or Silencer Device” E. Definition of “Privately Made Firearm” F. Definition of “Importer's or Manufacturer's Serial Number” G. Definition of “Gunsmith” H. Marking Requirements for Firearms I. Recordkeeping J. Record Retention K. Effect on Prior ATF Rulings and Procedures L. Severability VI. Statutory and Executive Order Review A. Executive Orders 12866 and 13563 B. Executive Order 13132 C. Executive Order 12988 D. Regulatory Flexibility Act E. Small Business Regulatory Enforcement Fairness Act of 1996 F. Congressional Review Act G. Unfunded Mandates Reform Act of 1995 H. Paperwork Reduction Act of 1995 I. Executive Summary A. Summary of the Regulatory Action There are no statutory definitions for the terms “frame” or “receiver” in the Gun Control Act of 1968 (“GCA”) or the National Firearms Act of 1934 (“NFA”). To implement these statutes, the terms “firearm frame or receiver” and “frame or receiver” were defined in regulations to mean “[t]hat part of a firearm which provides housing for the hammer, bolt or breechblock, and firing mechanism, and which is usually threaded at its forward portion to receive the barrel.” 27 CFR 478.11 (implementing GCA, Title I); 27 CFR 479.11 1 (implementing GCA, Title II). These definitions were meant to provide direction as to which portion of a weapon is the frame or receiver for purposes of licensing, serialization, and recordkeeping, thereby ensuring that a component necessary for the functioning of the weapon could be traced if later involved in a crime. 1 The definition of “frame or receiver” in section 479.11 differs slightly from the definition in section 478.11 in that it omits an Oxford comma between “bolt or breechblock” and “firing mechanism.” However, a restrictive application of these definitions would not describe the frame or receiver of most firearms currently in circulation in the United States. Most modern weapon designs, including semiautomatic rifles and pistols with detachable magazines, have a split or multi-piece receiver where the relevant fire control components are housed by more than one part of the weapon ( e.g., the upper receiver and lower receiver of an AR-15 rifle), or incorporate a striker to fire the weapon, rather than a hammer. In the past few years, some courts have treated the regulatory definition of “firearm frame or receiver” as inflexible when applied to the lower portion of the AR-15-type rifle, one of the most popular firearms in the United States. If broadly followed, that result could mean that as many as 90 percent of all firearms ( i.e., with split frames or receivers, or striker-fired) in the United States would not have any frame or receiver subject to regulation. Furthermore, technological advances have also made it easier for companies to sell firearm parts kits, standalone frame or receiver parts, and easy-to-complete frames or receivers to unlicensed persons, without maintaining any records or conducting a background check. These parts kits, standalone frame or receiver parts, or partially complete frames or receivers enable individuals to make firearms quickly and easily. Such privately made firearms (“PMFs”), when made for personal use, are not required by the GCA to have a serial number placed on the frame or receiver, making it difficult for law enforcement to determine where, by whom, or when they were manufactured, and to whom they were sold or otherwise transferred. Because of the difficulty with tracing illegally sold or distributed PMFs, those firearms are also commonly referred to as “ghost guns.” For these many reasons, ATF is promulgating a rule that would bring clarity to the definition of “frame or receiver” by providing an updated, more comprehensive definition. On May 21, 2021, the Department published a Notice of Proposed Rulemaking (“NPRM”) in the Federal Register , 86 FR 27720, proposing to redefine the term “frame or receiver” as that which provides housing or a structure to hold or integrate one or more fire control components. In light of the comments received, this final rule revises the proposed definition of “frame or receiver” so that a “frame” is applicable to a handgun, and variants thereof, and a “receiver” is applicable to a rifle, shotgun, or projectile weapon other than a handgun, and variants thereof. Moreover, “frame or receiver” will be defined to describe only a single part that provides housing or a structure for one specific, primary fire control component of weapons that expel a projectile, or one specific, primary internal sound reduction component of firearm mufflers or silencers. The final rule also defines the meaning of “variants” and “variants thereof.” The final rule provides detailed examples along with pictures identifying the frame or receiver of a variety of common models under the updated definition. The final rule also exempts from the new definitions and marking requirements existing split frame or receiver designs in which a part was previously classified by ATF as the firearm “frame or receiver” and provides examples and pictures of select exempted frames or receivers, such as AR-15/M-16 variant firearms. The only exception to “grandfathering” will be for partially complete, disassembled, or nonfunctional frames or receivers, including weapon or frame or receiver parts kits, that ATF did not classify as firearm “frames or receivers” as defined prior to this rule. The final rule also specifies, with more clarity and examples than the NPRM, how these terms apply to multi-piece frames or receivers ( i.e., those that may be disassembled into multiple modular subparts), to firearm mufflers and silencers, to partially complete, disassembled, or nonfunctional frames or receivers, including frame or receiver parts kits, and to frames or receivers that are destroyed. The final rule also provides detailed examples of when such items are considered readily completed, assembled, restored, or otherwise “converted” to function as a frame or receiver. At the same time, the final rule makes clear that articles that have not yet reached a stage of manufacture where they are clearly identifiable as an unfinished component of a frame or receiver ( e.g., unformed blocks of metal, liquid polymers, or other raw materials) are not frames or receivers. Consistent with the GCA, and to ensure proper licensing, marking, recordkeeping, and background checks with respect to certain weapon parts kits, the final rule adopts the proposed clarification of the term “firearm” to include weapon ( e.g., pistol, revolver, rifle, or shotgun) parts kits that are designed to or may readily be completed, assembled, restored, or otherwise converted to expel a projectile by the action of an explosive. This rule also finalizes, with minor changes, the proposed definition of “privately made firearm.” It amends the regulations to require that all firearms privately manufactured or “made” by nonlicensees without identifying markings that are taken into inventory by licensees be identified (or marked) and recorded so that they may be traced by law enforcement through their records if they are later involved in crime. As with the NPRM, the final rule does not mandate unlicensed persons to mark their own PMFs for personal use, or when they occasionally acquire them for a personal collection or sell or transfer them from a personal collection to unlicensed in-State residents consistent with Federal, State, and local law. In addition, the rule finalizes the proposed amendments to the term “gunsmith” to include persons who engage in the business of identifying firearms for nonlicensees, thus ensuring greater access to professional marking services for PMFs. The final rule clarifies the gunsmithing rules proposed in the NPRM by stating the following: (1) Licensed firearms dealers (in addition to licensed manufacturers and importers) may conduct same-day adjustments or repairs of all firearms, including PMFs, without taking them into inventory, provided they are returned to the person from whom they were received; (2) nonlicensees may mark PMFs for a licensee under the licensee's direct supervision; and (3) licensees may adopt an existing unique identification number previously placed on a PMF by a nonlicensee under certain conditions. In response to comments, the final rule permits licensed manufacturers to adopt the serial number and other identifying markings previously placed on a firearm without a variance from ATF, provided the firearm has not been sold, shipped, or otherwise disposed of to a person who is not a licensed manufacturer, superseding ATF Ruling 2009-5. The rule permits licensed manufacturers to perform gunsmithing services on existing, marked firearms without marking or obtaining a marking variance, superseding ATF Ruling 2010-10. It also finalizes, with some modifications, the proposed definition of the term “importer's or manufacturer's serial number” to help ensure that the serial number and associated identifying markings required to be placed on a firearm, including those placed on a PMF or an ATF-issued serial number, 2 are considered the “importer's or manufacturer's serial number” protected by 18 U.S.C. 922(k), which prohibits possession or receipt of a firearm that has had the importer's or manufacturer's serial number removed, obliterated, or altered. 2 ATF occasionally issues serial numbers for placement on firearms in which the serial numbers were not originally placed, see 26 U.S.C. 5842(b), or were accidentally removed, damaged, or worn due to routine use or other innocent reason. The final rule adopts, with minor clarifying changes, the proposed clarifications to the marking and recordkeeping requirements for licensees. First, the rule finalizes the definitions for “complete weapon” and “complete muffler or silencer device,” and adds a new definition for “multi-piece frame or receiver” under the new definition of “frame or receiver.” The rule also specifies a reasonable time period in which a complete weapon or a complete muffler or silencer device, or the frame or receiver of a weapon or device (including a modular subpart of a multi-piece frame or receiver), must be marked with a serial number and other identifying information and recorded. Second, the rule finalizes the proposed updates to the information required to be marked on the frame or receiver, clarifies the meaning of the marking terms “identify,” “legibly,” and “conspicuously,” and authorizes firearms licensees to adopt identifying markings in the manufacturing process. Third, the rule finalizes the proposal to require all licensees to consolidate their records of manufacture, acquisition, and disposition of firearms, and to eliminate duplicate recordkeeping entries. Fourth, with respect to parts defined as firearm mufflers or silencers, which are difficult to mark and record, this rule finalizes with minor clarifying changes the proposed amendments that allow for them to be transferred between licensees qualified under the NFA for purposes of further manufacture or repair of complete devices without immediately marking and registering them in the National Firearms Registration and Transfer Record (“NFRTR”). Fifth, the rule finalizes with minor clarifying changes the proposed amendments that set forth the process by which persons may voluntarily seek a determination from ATF on whether an item or kit they wish to manufacture or possess is a firearm or armor piercing ammunition subject to marking, recordkeeping, and other applicable Federal laws and regulations. These amendments to the regulations will help ensure that firearms can be traced efficiently and effectively by law enforcement through the records of licensees, and help prevent the acquisition of easy-to-complete firearms by prohibited persons and terrorists. Lastly, the rule finalizes with minor changes the proposed requirement that all licensees retain their records until the business or licensed activity is discontinued, either on paper or in an electronic format approved by the Director of ATF (“Director”), at the business or collection premises readily accessible for inspection. This includes authorization of licensees to store their “closed out” paper records and forms older than 20 years at a separate warehouse, which would be considered part of the business or collection premises for this purpose and subject to inspection. These provisions will enhance public safety by ensuring that acquisition and disposition records of all active licensees are not destroyed after 20 years and will remain available to law enforcement for tracing purposes. B. Summary of Costs and Benefits The final rule clarifies which firearms are subject to regulation under the GCA and NFA and associated licensing, marking, and recordkeeping requirements. The rule requires persons who engage in the business of dealing in weapon and frame or receiver parts kits defined as firearms to be licensed, mark the frames or receivers within such kits with serial numbers and other marks of identification, and maintain records of their acquisition and disposition. The provisions of these statutes and implementing regulations are designed to increase public safety by, among other things, preventing prohibited persons from acquiring firearms and allowing law enforcement to trace firearms involved in crime. To minimize disruption and cost to the licensed firearms industry as much as possible, and in keeping with the public safety goals of the rule, this rule grandfathers existing complete frame or receiver designs previously determined by the Director to be the firearm “frame or receiver” of a given weapon. It does not grandfather partially complete, disassembled, or nonfunctional frames or receivers, including weapon or frame or receiver parts kits, that ATF did not classify as firearm “frames or receivers” as previously defined. ATF estimates that the 7 percent annualized cost of this rule is $14.3 million. II. Background The Attorney General is responsible for enforcing the Gun Control Act of 1968, as amended, and the National Firearms Act of 1934, as amended. 3 This responsibility includes the authority to promulgate regulations necessary to enforce the provisions of the GCA and NFA. See 18 U.S.C. 926(a); 26 U.S.C. 7801(a)(2)(A), 7805(a). 4 Congress and the Attorney General have delegated the responsibility for administering and enforcing the GCA and NFA to the Director of ATF, subject to the direction of the Attorney General and the Deputy Attorney General. See 26 U.S.C. 7801(a)(2); 28 U.S.C. 599A(b)(1), (c)(1); 28 CFR 0.130(a)(1)-(2); T.D. Order No. 221(2)(a), (d), 37 FR 11696-97 (June 10, 1972). Accordingly, the Department and ATF have promulgated regulations to implement the GCA and NFA. See 27 CFR parts 478, 479. 3 NFA provisions still refer to the “Secretary of the Treasury.” See generally 26 U.S.C. ch. 53. However, the Homeland Security Act of 2002, Public Law 107-296, 116 Stat. 2135, transferred the functions of ATF from the Department of the Treasury to the Department of Justice, under the general authority of the Attorney General. 26 U.S.C. 7801(a)(2); 28 U.S.C. 599A(c)(1). Thus, for ease of reference, this final rule refers to the Attorney General throughout. 4 See also footnote 82, infra, for specific grants of rulemaking authority. On May 21, 2021, the Department published in the Federal Register a Notice of Proposed Rulemaking (“NPRM”) entitled “Definition of `Frame or Receiver' and Identification of Firearms,” 86 FR 27720, proposing changes to various regulations in 27 CFR parts 447, 478, and 479. The comment period for the proposed rule concluded on August 19, 2021, and ATF received 290,031 comments. The NPRM provided a comprehensive explanation of the passage of the Federal Firearms Act of 1938 (“FFA”), Public Law 75-785, 52 Stat. 1250, its repeal, and the subsequent legislative history and context leading to Congress's passage of the GCA in 1968, as well as the promulgation of the definitions for “frame or receiver” that ATF and the firearms industry have relied on for more than 50 years. 5 86 FR at 27720-21. The GCA at 18 U.S.C. 921(a)(3) defines the term “firearm” to include not only a weapon that will, is designed to, or may readily be converted to expel a projectile, but also the “frame” or “receiver” of any such weapon. 18 U.S.C. 921(a)(3)(A), (B). Because frames or receivers are included in the definition of “firearm,” any person who engages in the business of manufacturing, importing, or dealing in frames or receivers must obtain a license from ATF. 18 U.S.C. 922(a)(1)(A), 923(a). Each licensed manufacturer or importer must “identify by means of a serial number engraved or cast on the receiver or frame of the weapon, in such manner as the Attorney General shall by regulations prescribe, each firearm imported or manufactured by such importer or manufacturer.” 6 18 U.S.C. 923(i); see 27 CFR 478.92, 479.102. Licensed manufacturers and importers must also maintain permanent records of production or importation, as well as their receipt, sale, or other disposition of firearms, including frames or receivers. 18 U.S.C. 923(g)(1)(A); 27 CFR 478.122, 478.123. 5 The Omnibus Crime Control and Safe Streets Act of 1968 repealed the FFA and was then incorporated into and expanded by the GCA. Public Law 90-351, secs. 906-07, 82 Stat. 197, 234-35 (1968); Public Law 90-618, 82 Stat. 1213 (1968). 6 Additionally, a firearm frame or receiver that is not a component part of a complete weapon at the time it is sold, shipped, or disposed of must be identified in the manner prescribed with a serial number and all of the other required markings. 27 CFR 478.92(a)(2), 479.102(e); ATF Rul. 2012-1. The GCA does not define the terms “frame” or “receiver” to implement the statute, but frames or receivers are the primary structural components of a firearm to which fire control components are attached. 7 After the GCA was enacted, the terms “firearm frame or receiver” and “frame or receiver” were defined as “that part of a firearm which provides housing for the hammer, bolt or breechblock, and firing mechanism, and which is usually threaded at its forward portion to receive the barrel.” 27 CFR 478.11 (implementing GCA, Title I); 8 27 CFR 479.11 (implementing GCA, Title II). 9 The intent in promulgating these definitions was to inform the public and industry as to which portion of a firearm was the frame or receiver for purposes of licensing, serialization, and recordkeeping, thus ensuring that a necessary component of the weapon could be traced if later involved in a crime. 7 See Webster's Third New International Dictionary 902, 1894 (1971) (a “frame” is “the basic unit of a handgun which serves as a mounting for the barrel and operating parts of the arm”; “receiver” means “the metal frame in which the action of a firearm is fitted and to which the breech end of the barrel is attached”); John Olson, Olson's Encyclopedia of Small Arms 72 (1985) (the term “frame” means “the basic structure and principal component of a firearm”); Steindler's New Firearms Dictionary, p. 209 (1985) (“receiver” means “that part of a rifle or shotgun . . . that houses the bolt, firing pin, mainspring, trigger group, and magazine or ammunition feed system. The barrel is threaded into the somewhat enlarged forward part of the receiver, called the receiver ring. At the rear of the receiver, the butt or stock is fastened. In semiautomatic pistols, the frame or housing is sometimes referred to as the receiver”). 8 See 33 FR 18558 (Dec. 14, 1968) (formerly 26 CFR 178.11). 9 See 36 FR 14257 (Aug. 3, 1971) (formerly 26 CFR 179.11). The NPRM discussed that at the time the regulatory definitions were promulgated, single-framed firearms such as revolvers and break-open shotguns were far more prevalent for civilian ( i.e., not military or law enforcement) use in the United States than split receiver weapons, such as semiautomatic rifles and pistols with detachable magazines. Single-framed firearms incorporate the hammer, bolt or breechblock, and firing mechanism within the same housing. 86 FR at 27721. Over time, split receiver firearms became popular for civilian use, such as the AR-15 semiautomatic rifle (upper receiver and lower receiver), Glock semiautomatic pistol (upper slide assembly and lower grip module), and Sig Sauer P320 pistol (M17/18 as adopted by the U.S. military) (upper slide assembly, chassis, and lower grip module). And more firearm manufacturers began incorporating a striker-fired mechanism, rather than a “hammer,” in the firing design, such as in the Glock pistol. Id. A. ATF's Application of the Definitions to Split Frames and Receivers The NPRM explained that ATF's regulatory definitions of “frame or receiver” do not expressly capture these types of firearms ( i.e., split frames or receivers) that now constitute the majority of firearms in the United States. 10 However, ATF's position has long been that the weapon “should be examined with a view toward determining if [either] the upper or lower half of the receiver more nearly fits the legal definition of `receiver,' ” and more specifically, for machineguns, whether the upper or lower portion has the ability to accept machinegun parts. 11 12 The NPRM listed the variety of factors ATF has considered when making determinations for firearm classifications under the GCA and NFA regarding which part of a firearm is the frame or receiver, given that neither a split nor a multi-piece receiver has a portion of its design that falls within the precise wording of the existing regulatory definition. 86 FR at 27721. 10 United States v. Rowold, 429 F. Supp. 3d 469 (N.D. Ohio 2019), Testimony of ATF Firearms Enforcement Officer Daniel Hoffman at Doc. No. 60, Hrg. Tr., Page ID 557 (approximately 10 percent of currently manufactured firearms in the United States include at least three components in the frame or receiver definition), and Defense Expert Daniel O'Kelly at Doc. No. 60, Hrg. Tr., Page ID 482 (“90 some percent of [semiautomatic pistols] do not have a part which has more than one of these four elements in it and, therefore, don't qualify, according to the definition in the CFR.”). 11 ATF Internal Revenue Service Memorandum #21208 (Mar. 1, 1971) (lower portion of the M-16 is the frame or receiver because it comes closest to meeting the definition of frame or receiver in 26 CFR 178.11 (now 27 CFR 478.11), and is the receiver of a machinegun as defined in the NFA); ATF Memorandum #22334 (Jan. 24, 1977) (upper half of the FN-FAL rifle is the frame or receiver because it was designed to accept the components that allow fully automatic fire). The ability to accept machinegun parts is considered because both the GCA and the NFA regulate machinegun receivers as “machineguns.” See 18 U.S.C. 921(a)(23); 26 U.S.C. 5845(b) (“The term [“machinegun”] shall also include the frame or receiver of any such weapon [which shoots is designed to shoot, or can be readily restored to shoot, automatically more than one shot, without manual reloading, by a single function of the trigger].”). 12 Regulations implementing the relevant statutes spell the term “machine gun” rather than “machinegun.” E.g., 27 CFR 478.11, 479.11. For convenience, this rule uses “machinegun,” except when quoting a source to the contrary. Indeed, the current definitions were never intended, or understood, to be exhaustive. The Department discussed in the NPRM the existing law and congressional intent recognizing that the definition of “frame or receiver” need not be limited to a strict application of the regulation. Id. at 27721-22. At the time the current definitions were adopted, there were numerous models of firearms that did not contain a part that fully met the regulatory definition of “frame or receiver,” such as the Colt 1911, FN-FAL, and the AR-15/M-16, all of which were originally manufactured almost exclusively for military use. ATF has long applied the factors stated in the NPRM when determining which component of those weapons qualifies as the frame or receiver. 13 13 See footnote 11, supra. While ATF for decades has classified the lower receiver of the AR-15 rifle as a “frame or receiver,” some courts recently have treated the regulatory definition as inflexible when applied to the lower portion of the AR-15-type rifle, which is the semiautomatic version of the M-16-type machinegun originally designed for the U.S. military. That was because those courts have read the regulatory definition to mean that the lower portion of the AR-15 is not a “frame or receiver,” as it provides housing only for the hammer and firing mechanism, not the bolt or breechblock. See United States v. Rowold, 429 F. Supp. 3d 469, 475-76 (N.D. Ohio 2019). (“The language of the regulatory definition in § 478.11 lends itself to only one interpretation: Namely, that under the GCA, the receiver of a firearm must be a single unit that holds three, not two components: (1) The hammer, (2) the bolt or breechblock, and (3) the firing mechanism.”); see also United States v. Roh, 8:14-cr-00167-JVS, Minute Order p. 6 (C.D. Cal. July 27, 2020); United States v. Jimenez, 191 F. Supp. 3d 1038, 1041 (N.D. Cal. 2016). The NPRM explained that, if broadly followed, these courts' interpretation of ATF's regulations could mean that as many as 90 percent of all firearms now in the United States would not have any frame or receiver subject to regulation under the current definitions. 14 Those firearms would include numerous widely available models, such as Glock-type and Sig Sauer P320 15 pistols, that do not utilize a hammer—a named component in the existing regulatory definition—in the firing sequence. Such a narrow interpretation of what constitutes a frame or receiver would allow persons to avoid obtaining a license to engage in the business of manufacturing or importing upper or lower frames or receivers, which would further allow those persons to avoid the GCA's marking, recordkeeping, and background check requirements pertaining to upper or lower frames or receivers. See 86 FR at 27722. In turn, prohibited persons may more easily and without a background check acquire upper and lower receivers that can quickly be assembled into semiautomatic weapons. 16 Moreover, law enforcement's ability to trace semiautomatic firearms later used in crime would be severely impeded if no portion of split or multi-piece frames or receivers were subject to any existing regulations as described. This result would undermine the intent of Congress in requiring the frame or receiver of every firearm to be identified, see 18 U.S.C. 923(i), and regulated as a firearm, see 18 U.S.C. 921(a)(3)(B). 14 See footnote 10, supra. 15 The United States military services have adopted variants of the Sig Sauer P320 as their official sidearm, and are in the process of purchasing up to 500,000 of these striker-fired pistols. Matthew Cox & Hope Hodge Seck, Army Picks Sig Sauer's P320 Handgun to Replace M9 Service Pistol, Military.com (Jan. 19, 2017), available at https://www.military.com/daily-news/2017/01/19/army-picks-sig-sauer-replace-m9-service-pistol.html (last visited Mar. 22, 2022); Jared Keller, Every U.S. military branch is about to get its hands on the Army's new sidearm of choice, Taskandpurpose.com (Nov. 18, 2020), available at https://taskandpurpose.com/military-tech/modular-handgun-system-fielding (last visited Mar. 22, 2022) (Sig Sauer delivered its 200,000th P320-variant pistol to the military despite the obstacles posed by the novel coronavirus). 16 See Jake Bleiberg & Stefanie Dazio, Design of AR-15 could derail charges tied to popular rifle, APnews.com (Jan. 13, 2020), available at https://apnews.com/article/396bbedbf4963a28bda99e7793ee6366 (last visited Mar. 22, 2022); Dan Morse & Jasmine Hilton, Magruder [High School] student bought `ghost gun' components online before wounding classmate, Wash. Post (Jan. 24, 2022), available at https://www.washingtonpost.com/dc-md-va/2022/01/24/magruder-shooting-teen-jailed (last visited Mar. 22, 2022). B. Privately Made Firearms The NPRM explained that technological advances have also made it easier for companies to sell firearm parts kits, standalone frame or receiver parts, or partially complete frames or receivers to unlicensed persons, posing significant challenges to the regulation of frames and receivers and enabling prohibited individuals to easily make firearms at home, especially if aided by personally owned equipment or 3D printers. These privately made firearms, commonly referred to as “ghost guns,” are not required by the GCA to have a serial number placed on the frame or receiver when made for personal use. When PMFs are relinquished by their owners, enter commerce, and are later recovered and submitted for tracing, the absence of markings on PMFs makes it extremely difficult for law enforcement to determine where, by whom, or when they were manufactured, and to whom they were sold or otherwise disposed. The NPRM discussed the substantial increase in the number of PMFs recovered from crime scenes throughout the country in recent years. 17 From January 1, 2016, through December 31, 2021, there were approximately 45,240 suspected PMFs reported to ATF as having been recovered by law enforcement from potential crime scenes, including 692 homicides or attempted homicides ( not including suicides), and which ATF attempted to trace. Broken down by calendar year, the total annual numbers of suspected PMFs recovered show significant proliferation over the past six years: 2016: 1,758; 2017: 2,552; 2018: 3,960; 2019: 7,517; 2020: 10,109; 2021: 19,344. 18 19 17 86 FR at 27722 n.17. See also Erik von Ancken, Untraceable `Ghost Guns' sold across Central Florida, WKMG-TV Orlando (Nov. 15, 2016), available at https://www.clickorlando.com/getting-results/2016/11/15/untraceable-ghost-guns-sold-across-central-florida (last visited Mar. 22, 2022); Nicholas J. Simons, Ghost Guns: A Haunting New Reality, Rockefeller Institute of Justice (2021), available at https://rockinst.org/wp-content/uploads/2021/04/210413-Ghost-Guns-web.pdf (last visited Mar. 22, 2022); Travis Taniguchi et al., The Proliferation of Ghost Guns: Regulation Gaps and Challenges for Law Enforcement, National Police Foundation (2021), available at https://www.policefoundation.org/wp-content/uploads/2021/08/NPF_The-Proliferation-of-Ghost-Guns_Final_2021.pdf (last visited Mar. 22, 2022); Shanzeh Ahmad & Jeremy Gorner, `We're seeing an explosion:' Sheriff Tom Dart, state Sen. Jacqueline Collins take aim at ghost guns, propose legislation to ban the untraceable weapons, Chi. Trib. (Oct. 14, 2021), available at https://www.chicagotribune.com/news/breaking/ct-cook-county-sheriff-dart-ghost-gun-legislation-20211014-whvwjv5aangmtaje27gpllqtvu-story.html (last visited Mar. 22, 2022); Brian X. McCrone, `3 Pipes Turned into a Shotgun': Nearly 1-in-10 Guns Seized in Philly Are Homemade, NBC10 Philadelphia (Oct. 7, 2021), available at https://www.nbcphiladelphia.com/news/local/three-metal-pipes-turned-into-a-shotgun-nearly-1-in-10-guns-seized-in-philly-are-homemade/2983066 (last visited Mar. 22, 2022); Kevin Rector, LAPD declares `ghost guns' an `epidemic,' citing 400% increase in seizures, L.A. Times (Oct. 15, 2021), available at https://www.latimes.com/california/story/2021-10-15/lapd-says-ghost-guns-an-epidemic-with-seizures-up-400-since-2017 (last visited Mar. 22, 2022); Glenn Thrush, `Ghost Guns': Firearm Kits Bought Online Fuel Epidemic of Violence, N.Y. Times (Nov. 14, 2021), available at https://www.nytimes.com/2021/11/14/us/ghost-guns-homemade-firearms.html (last visited Mar. 22. 2022). 18 Source: ATF Office of Strategic Intelligence and Information. These numbers (as of January 21, 2022) are likely far lower than the actual number of PMFs recovered from crime scenes because some law enforcement departments incorrectly trace some PMFs as commercially manufactured firearms, or may not see a need to use their resources to attempt to trace firearms with no serial numbers or other identifiable markings. The term “suspected PMF” is used because of the difficulty of getting law enforcement officials to uniformly enter PMF trace information into ATF's electronic tracing system (“eTrace”), resulting in reporting inconsistencies of PMFs involved in crime. For example, often PMFs resemble commercially manufactured firearms, or incorporate parts from commercially manufactured firearms bearing that manufacturer's name, so some firearms suspected of being PMFs were entered into eTrace using a commercial manufacturer's name rather than as one privately made by individuals. The term “potential crime scenes” is used because ATF does not know if the firearm being traced by the law enforcement agency was found at a crime scene as opposed to one recovered by law enforcement that had been stolen or otherwise not from the scene of a crime. This is because the recovery location or correlated crime is not always communicated by the agency to ATF in the tracing process. 19 The total number of suspected PMFs is greater than the 23,906 originally queried and reported as of March 4, 2021, in the NPRM, 86 FR at 27722-23, due, not only to the addition of CY 2021 data, but also to traces being updated with more specificity regarding the firearm description since that date, and the inclusion of all suspected PMFs recovered within this time frame regardless of when the trace was entered. ER26AP22.000 Numerous criminal cases have been brought by the Department to counter the illegal trafficking of unserialized privately completed and assembled weapons, the possession of such weapons by prohibited persons, and other related Federal crimes. 20 20 86 FR 27723 n.19. See also Dark Web Gun Trafficker from Nevada County Pleads Guilty to Unlawful Dealing in Firearms, DOJ/OPA (June 22, 2018), available at https://www.justice.gov/usao-edca/pr/dark-web-gun-trafficker-nevada-county-pleads-guilty-unlawful-dealing-firearms; Burlington Man Pleads Guilty to Ammunition Charge, DOJ/OPA (Dec. 12, 2018), available at https://www.justice.gov/usao-ma/pr/burlington-man-pleads-guilty-ammunition-charge; Burlington Man Sentenced For Ammunition Charge, DOJ/OPA (Mar. 19, 2019), available at https://www.justice.gov/usao-ma/pr/burlington-man-sentenced-ammunition-charge; Indiana Residents Indicted on Terrorism and Firearms Charges, DOJ/OPA (July 11, 2019), available at https://www.justice.gov/opa/pr/indiana-residents-indicted-terrorism-and-firearms-charges; Las Vegas Man Charged For Illegally Engaging In The Business Of Manufacturing Machine Guns Without A License, DOJ/OPA (Sept. 4, 2019), available at https://www.justice.gov/usao-nv/pr/las-vegas-man-charged-illegally-engaging-business-manufacturing-machine-guns-without; Two Stockton Residents Sentenced for Firearms Offenses, DOJ/OPA (Nov. 21, 2019), available at https://www.justice.gov/usao-edca/pr/two-stockton-residents-sentenced-firearms-offenses; Denver Gang Member Sentenced To Over 15 Years In Federal Prison For Making And Selling Dozens Of High Powered Guns, Including Machine Guns And Silencers, DOJ/OPA (Nov. 22, 2019), available at https://www.justice.gov/usao-co/pr/denver-gang-member-sentenced-over-15-years-federal-prison-making-and-selling-dozens-high; Cedar Rapids Man Pleads Guilty to Drug Trafficking and Possessing Machineguns and a Pipe Bomb, DOJ/OPA (Jan. 21, 2020), available at https://www.justice.gov/usao-ndia/pr/cedar-rapids-man-pleads-guilty-drug-trafficking-and-possessing-machineguns-and-pipe; Indictment Charges 15 Members of a Los Angeles Drug Trafficking Ring that Distributed Heroin, Methamphetamine and Cocaine, DOJ/OPA (Feb. 12, 2020), available at https://www.justice.gov/usao-cdca/pr/indictment-charges-15-members-los-angeles-drug-trafficking-ring-distributed-heroin; Two Queens Men Charged After Buying Three Illegally Defaced Firearms and Two Assault Rifles, DOJ/OPA (May 13, 2020), available at https://www.justice.gov/usao-edny/pr/two-queens-men-charged-after-buying-three-illegally-defaced-firearms-and-two-assault; Second Defendant Charged with Murder in New Indictment in Case of Man Found Dead in Pacific Ocean after Being Shot on a Boat, DOJ/OPA (June 25, 2020), available at https://www.justice.gov/usao-cdca/pr/second-defendant-charged-murder-new-indictment-case-man-found-dead-pacific-ocean-after; Fishers residents indicted on terrorism and firearms charges, DOJ/OPA (July 12, 2019), available at https://www.justice.gov/usao-sdin/pr/fishers-residents-indicted-terrorism-and-firearms-charges; Outlaws Motorcycle Club Regional President Pleads Guilty to Firearms Charges, DOJ/OPA (July 15, 2020), available at https://www.justice.gov/usao-ma/pr/outlaws-motorcycle-club-regional-president-pleads-guilty-firearms-charges; Sun Valley Man Indicted on Federal Narcotics Charges and Weapons Offenses, including Possession of Ghost Gun and Grenade Launcher, DOJ/OPA (July 23, 2020), available at https://www.justice.gov/usao-cdca/pr/sun-valley-man-indicted-federal-narcotics-charges-and-weapons-offenses-including; Seven Defendants Arrested and Charged in Conspiracy to Possess and Carry Firearms in Furtherance of Drug Trafficking, DOJ/OPA (Sept. 3, 2020), available at https://www.justice.gov/usao-dc/pr/seven-defendants-arrested-and-charged-conspiracy-possess-and-carry-firearms-furtherance; Takedown Completes Arrests of 15 Alleged Drug Traffickers in Syracuse Area, DOJ/OPA (Sept. 17, 2020), available at https://www.justice.gov/usao-ndny/pr/takedown-completes-arrests-15-alleged-drug-traffickers-syracuse-area; Three Members of Gardena Street Gang Charged in Federal Racketeering Case Alleging Murder of Man Outside His Home, DOJ/OPA (Dec. 2, 2020), available at https://www.justice.gov/usao-cdca/pr/three-members-gardena-street-gang-charged-federal-racketeering-case-alleging-murder-man; Syracuse Man Pleads Guilty to Brokering Illegal Gun Sales, DOJ/OPA (Dec. 9, 2020), available at https://www.justice.gov/usao-ndny/pr/syracuse-man-pleads-guilty-brokering-illegal-gun-sales; Gang Member Sentenced to More Than 7 Years in Prison for Gun and Drug Offenses, DOJ/OPA (Feb. 17, 2021), available at https://www.justice.gov/usao-ct/pr/gang-member-sentenced-more-7-years-prison-gun-and-drug-offenses; Man Sentenced for Attempting to Board International Flight with a Loaded Firearm, DOJ/OPA (Mar. 12, 2021), available at https://www.justice.gov/usao-sdca/pr/man-sentenced-attempting-board-international-flight-loaded-firearm; Vacaville Man Sentenced to over 4 Years in Prison for Unlawfully Possessing Ammunition as a Felon, DOJ/OPA (May 4, 2021), available at https://www.justice.gov/usao-edca/pr/vacaville-man-sentenced-over-4-years-prison-unlawfully-possessing-ammunition-felon; Big Island man arrested on methamphetamine and firearm charges, DOJ/OPA (May 18, 2021), available at https://www.justice.gov/usao-hi/pr/big-island-man-arrested-methamphetamine-and-firearm-charges; Fresno Gang Member Faces Federal Firearms Charge, DOJ/OPA (June 3, 2021), available at https://www.justice.gov/usao-edca/pr/fresno-gang-member-faces-federal-firearms-charge; Temple Hills Man Sentenced To Three And A Half Years In Federal Prison For Trafficking Of Ghost Guns, DOJ/OPA (June 4, 2021), available at https://www.justice.gov/usao-md/pr/temple-hills-man-sentenced-three-and-half-years-federal-prison-trafficking-ghost-guns; Septuagenarian charged with manufacturing “ghost guns”, DOJ/OPA (June 15, 2021), available at https://www.justice.gov/usao-sdtx/pr/septuagenarian-charged-manufacturing-ghost-guns; Convicted Gun Trafficker Pleads Guilty to Firearms Charges, DOJ/OPA (June 22, 2021), available at https://www.justice.gov/usao-ndny/pr/convicted-gun-trafficker-pleads-guilty-firearms-charges; Barnstable Man Charged with Firearm Trafficking, DOJ/OPA (June 22, 2021), available at https://www.justice.gov/usao-ma/pr/barnstable-man-charged-firearm-trafficking; Laplace Man Pleads Guilty to Being Felon in Possession of Ammunition, DOJ/OPA (June 25, 2021), available at https://www.justice.gov/usao-edla/pr/laplace-man-pleads-guilty-being-felon-possession-ammunition; Felon Pleads Guilty to Possession of Ghost Guns and Conspiracy to Commit Wire Fraud, DOJ/OPA (June 28, 2021), available at https://www.justice.gov/usao-md/pr/felon-pleads-guilty-possession-ghost-guns-and-conspiracy-commit-wire-fraud; Syracuse Man Sentenced to Seven Years in Federal Prison for Brokering Illegal Gun Sales, DOJ/OPA (July 8, 2021), available at https://www.justice.gov/usao-ndny/pr/syracuse-man-sentenced-seven-years-federal-prison-brokering-illegal-gun-sales; Federal Drug and Gun Charges Brought Against Fresno Man Accused of Dealing Fentanyl, DOJ/OPA (July 15, 2021), available at https://www.justice.gov/usao-edca/pr/federal-drug-and-gun-charges-brought-against-fresno-man-accused-dealing-fentanyl; Vineland Boys Gang Member Sentenced to 31 Years in Federal Prison for Racketeering Conspiracy, Attempted Murder of Rival Gangsters, DOJ/OPA (July 22, 2021), available at https://www.justice.gov/usao-cdca/pr/vineland-boys-gang-member-sentenced-31-years-federal-prison-racketeering-conspiracy; Hartford Man Charged with Illegally Possessing Firearm and Ammunition, DOJ/OPA (July 23, 2021), available at https://www.justice.gov/usao-ct/pr/hartford-man-charged-illegally-possessing-firearm-and-ammunition; Philadelphia Man Arrested on Murder-For-Hire Charges; Attempted Homicide in Southwest Philadelphia Thwarted, DOJ/OPA (July 26, 2021), available at https://www.justice.gov/usao-edpa/pr/philadelphia-man-arrested-murder-hire-charges-attempted-homicide-southwest-philadelphia; Rensselaer County Felon Sentenced to 30 Months on Firearms Convictions, DOJ/OPA (Aug. 10, 2021), available at https://www.justice.gov/usao-ndny/pr/rensselaer-county-felon-sentenced-30-months-firearms-convictions; Three East Bay Men Charged With Conspiracy To Traffic Firearms, DOJ/OPA (Aug. 16, 2021), available at https://www.justice.gov/usao-ndca/pr/three-east-bay-men-charged-conspiracy-traffic-firearms; Raleigh Felon Sentenced After Pulling a Firearm on Officers During a Drug Investigation, DOJ/OPA (Aug. 17, 2021), available at https://www.justice.gov/usao-ednc/pr/raleigh-felon-sentenced-after-pulling-firearm-officers-during-drug-investigation; Buffalo Man Arrested, Charged With Manufacturing Ghost Guns, DOJ/OPA (Aug. 20, 2021), available at https://www.justice.gov/usao-wdny/pr/buffalo-man-arrested-charged-manufacturing-ghost-guns; Montgomery County Man Sentenced to 30 Months for Unlawfully Selling “Ghost Guns”, DOJ/OPA (Sept. 2, 2021), available at https://www.justice.gov/usao-ndny/pr/montgomery-county-man-sentenced-30-months-unlawfully-selling-ghost-guns; Three South Lake Tahoe Residents Charged with Drug Trafficking and Texas Man Charged with Trafficking Firearms, DOJ/OPA (Aug. 23, 2021), available at https://www.justice.gov/usao-edca/pr/three-south-lake-tahoe-residents-charged-drug-trafficking-and-texas-man-charged; New Mexico Man Who Sold `Ghost Guns' Indicted, DOJ/OPA (Sept. 8, 2021), available at https://www.justice.gov/usao-ndtx/pr/new-mexico-man-who-sold-ghost-guns-indicted; Fresno Men Indicted for Being Previously Convicted of Violent Crimes in Possession of Firearm and Ammunition, DOJ/OPA (Sept. 16, 2021), available at https://www.justice.gov/usao-edca/pr/fresno-men-indicted-being-previously-convicted-violent-crimes-possession-firearm-and; Connecticut Man Sentenced for Firearm Trafficking, DOJ/OPA (Sept. 16, 2021), available at https://www.justice.gov/usao-ma/pr/connecticut-man-sentenced-firearm-trafficking; Two Defendants Indicted For Oahu Game Room Robbery, Drug Trafficking, and “Ghost Gun” Possession, DOJ/OPA (Sept. 17, 2021), available at https://www.justice.gov/usao-hi/pr/two-defendants-indicted-oahu-game-room-robbery-drug-trafficking-and-ghost-gun-possession; D.C. Felon Sentenced to 30 Months In Federal Prison For Illegal Possession Of A .40 Caliber “Ghost Gun” Firearm And 10 Rounds Of Ammunition, DOJ/OPA (Sept. 24, 2021), available at https://www.justice.gov/usao-md/pr/dc-felon-sentenced-30-months-federal-prison-illegal-possession-40-caliber-ghost-gun; Convicted Felon Sentenced for Narcotics Trafficking and Manufacturing “Ghost Guns”, DOJ/OPA (Sept. 24, 2021), available at https://www.justice.gov/usao-edva/pr/convicted-felon-sentenced-narcotics-trafficking-and-manufacturing-ghost-guns; Two District Men Indicted on Federal Charges Involving Illegal Possession and Sale of Firearms, DOJ/OPA (Sept. 29, 2021), available at https://www.justice.gov/usao-dc/pr/two-district-men-indicted-federal-charges-involving-illegal-possession-and-sale-firearms; Bronx Man Who Possessed Five “Ghost Guns” Charged With Possessing A Firearm And Ammunition, DOJ/OPA (Oct. 5, 2021), available at https://www.justice.gov/usao-sdny/pr/bronx-man-who-possessed-five-ghost-guns-charged-possessing-firearm-and-ammunition; Fresno Felon Indicted for Possession of Ammunition, DOJ/OPA (Oct. 7, 2021), available at https://www.justice.gov/usao-edca/pr/fresno-felon-indicted-possession-ammunition; District Man Sentenced to 10 1/2 Years in Prison for Armed Robbery and Earlier Shooting, DOJ/OPA (Oct. 13, 2021), available at https://www.justice.gov/usao-dc/pr/district-man-sentenced-10-years-prison-armed-robbery-and- earlier-shooting; Brooklyn Felon Sentenced to 48 Months' Imprisonment for Possessing Arsenal of Weapons Including “Ghost Guns”, DOJ/OPA (Oct. 12, 2021), available at https://www.justice.gov/usao-edny/pr/brooklyn-felon-sentenced-48-months-imprisonment-possessing-arsenal-weapons-including; Syracuse Man Pleads Guilty to Unlawfully Possessing and Selling Firearms and Ammunition, DOJ/OPA (Oct. 15, 2021), available at https://www.justice.gov/usao-ndny/pr/syracuse-man-pleads-guilty-unlawfully-possessing-and-selling-firearms-and-ammunition; Two Men Indicted for Firearms Trafficking, DOJ/OPA (Oct. 28, 2021), available at https://www.justice.gov/usao-edca/pr/two-men-indicted-firearms-trafficking; Tattoo Shop Owner Sentenced to Prison for Possessing Unlicensed Firearms at his Business, DOJ/OPA (Oct. 28, 2021), available at https://www.justice.gov/usao-wdpa/pr/tattoo-shop-owner-sentenced-prison-possessing-unlicensed-firearms-his-business; Mexican National Charged with Possessing Firearms, Methamphetamine in Checked Luggage at MSP Airport, DOJ/OPA (Nov. 2, 2021), available at https://www.justice.gov/usao-mn/pr/mexican-national-charged-possessing-firearms-methamphetamine-checked-luggage-msp-airport; Lawrence Man Arrested on Firearms and Narcotics Charges, DOJ/OPA (Nov. 4, 2021), available at https://www.justice.gov/usao-ma/pr/lawrence-man-arrested-firearms-and-narcotics-charges; Colchester Man Sentenced to 34 Months in Federal Prison for Illegally Possessing Machinegun, DOJ/OPA (Nov. 12, 2021), available at https://www.justice.gov/usao-ct/pr/colchester-man-sentenced-34-months-federal-prison-illegally-possessing-machinegun; Ocean County Man Charged with Illegally Possessing Loaded Semi-Automatic Rifle, DOJ/OPA (Nov. 16, 2021), available at https://www.justice.gov/usao-nj/pr/ocean-county-man-charged-illegally-possessing-loaded-semi-automatic-rifle; New Haven Gang Member Charged with Federal Firearm and Narcotics Offenses, DOJ/OPA (Nov. 17, 2021), available at https://www.justice.gov/usao-ct/pr/new-haven-gang-member-charged-federal-firearm-and-narcotics-offenses; Edmund H. Mahony, Gang task force accuses two East Hartford men of using 3D printers to manufacture and sell hard-to-track `ghost guns,' Hartford Courant (Jan. 7, 2022), available at https://www.courant.com/news/connecticut/hc-news-ghost-gun-arrests-20220107-20220107-hqa4ggdygvfxdemh7kihaocqxy-story.html (last visited Mar. 22, 2022). The problem of untraceable firearms being acquired and used by violent criminals and terrorists is international in scope. 21 The NPRM highlighted Congress's concern, based on intelligence reports from the Department of Homeland Security (“DHS”), the Federal Bureau of Investigation (“FBI”), and the National Counterterrorism Center (“NCTC”), that untraceable firearms pose a challenge to law enforcement's ability to investigate crimes and that “wide availability of ghost guns and the emergence of functional 3D-printed guns are a homeland security threat.” 22 Numerous criminal investigations and studies have also demonstrated these concerns, 23 while several States and municipalities have banned or severely restricted unserialized or 3D-printed firearms. 24 21 Firearms using 3D-printed components seized in Sweden, Armament Research Services (May 19, 2017), available at https://armamentresearch.com/3d-printed-firearms-seized-in-sweden (last visited Mar. 22, 2022); Lizzie Dearden, Use of 3D printed guns in German synagogue shooting must act as warning to security services, experts say, independent.co.uk (Oct. 11, 2019), available at https://www.independent.co.uk/news/world/europe/3d-gun-print-germany-synagogue-shooting-stephan-balliet-neo-nazi-a9152746.html (last visited Mar. 22, 2022); G. Hays, Multiple 3D-printed Firearms Seized in Sydney, Australia, Armament Research Services (Aug. 11, 2020), available at https://armamentresearch.com/multiple-3d-printed-firearms-seized-in-sydney-australia (last visited Mar. 22, 2022); Glock ghost guns up for grabs on the dark web, Australian National University (Mar. 23, 2021), available at https://www.anu.edu.au/news/all-news/glock-ghost-guns-up-for-grabs-on-the-dark-web (last visited Mar. 22, 2022); Spain dismantles workshop making 3D-printed weapons, BBC (Apr. 19, 2021), available at https://www.bbc.com/news/world-europe-56798743 (last visited Mar. 22, 2022); Liam Reilly & Alaa Elassar, A Rhode Island man was arrested for allegedly selling `ghost guns' and trafficking firearms to the Dominican Republic, CNN (Jan. 9, 2022), available at https://www.cnn.com/2022/01/09/us/rhode-island-ghost-guns-dominican-republic/index.html (last visited Mar. 22, 2022). 22 H.R. Rep. No. 116-88, at 2 (2019). The House Report cited a January 11, 2019 Joint Intelligence Bulletin issued by DHS, FBI, and NCTC concluding that “these rapidly evolving technologies pose an ongoing, metastasizing challenge to law enforcement in understanding, tracking, and tracing ghost guns,” and an April 22, 2019 DHS intelligence assessment that “repeated the warning that ghost guns pose an urgent and evolving threat to the homeland, particularly in the hands of ideologically motivated lone wolf actors.” Id. 23 Paul Ingram, CBP: 3-D-printed full-auto rifle seized at Lukeville crossing, tucsonsentinel.com (Feb. 8, 2016), available at http://www.tucsonsentinel.com/local/report/020816_3d_printed_gun/cbp-3-d-printed-full-auto-rifle-seized-lukeville-crossing (last visited Mar. 22, 2022); Dark Web Gun Trafficker from Nevada County Pleads Guilty to Unlawful Dealing in Firearms, DOJ/OPA (June 22, 2018), available at https://www.justice.gov/usao-edca/pr/dark-web-gun-trafficker-nevada-county-pleads-guilty-unlawful-dealing-firearms; Mahita Gajanan, The TSA Has Found 3D-Printed Guns at Airport Checkpoints 4 Times Since 2016, Time (Aug. 2, 2018), available at https://time.com/5356179/3d-printed-guns-tsa (last visited Mar. 22, 2022); Grass Valley Man Sentenced to 5 Years in Prison for Unlawfully Manufacturing Ghost Guns and Selling Them on Dark Web, DOJ/OPA (Sept. 21, 2018), available at https://www.justice.gov/usao-edca/pr/grass-valley-man-sentenced-5-years-prison-unlawfully-manufacturing-ghost-guns-and; Indiana Residents Indicted on Terrorism and Firearms Charges, DOJ/OPA (July 11, 2019), available at https://www.justice.gov/opa/pr/indiana-residents-indicted-terrorism-and-firearms-charges; Fishers residents indicted on terrorism and firearms charges, DOJ/OPA (July 12, 2019), available at https://www.justice.gov/usao-sdin/pr/fishers-residents-indicted-terrorism-and-firearms-charges; Brandi Vincent, TSA Confiscated 3D-Printed Guns at Raleigh-Durham International Airport, nextgov.com (Mar. 4, 2020), available at https://www.nextgov.com/emerging-tech/2020/03/tsa-confiscated-3d-printed-guns-raleigh-durham-international-airport/163533 (last visited Mar. 22, 2022); Man Sentenced for Attempting to Board International Flight with a Loaded Firearm, DOJ/OPA (Mar. 12, 2021), available at https://www.justice.gov/usao-sdca/pr/man-sentenced-attempting-board-international-flight-loaded-firearm; Lizzie Dearden, Police issue warning over terrorist use of 3D-printed guns as UK neo-Nazi jailed, MSN News (June 14, 2021), available at https://www.msn.com/en-gb/news/uknews/police-issue-warning-over-terrorist-use-of-3d-printed-guns-as-uk-neo-nazi-jailed/ar-AAL2G36 (last visited Mar. 22. 2022); Davide Sher, Oceanian media report seizures of 3D printed guns, submachine guns, 3D Printing Media Network (June 22, 2021), https://www.3dprintingmedia.network/oceanian-media-report-seizures-of-3d-printed-guns-submachine-guns (last visited Mar. 22, 2022); Dr. Yannick Veilleux-Lepage, CTRL, HATE, PRINT: Terrorists and the appeal of 3D-printed weapons, International Centre for Counter-Terrorism (July 13, 2021), available at https://icct.nl/publication/ctrl-hate-print-terrorists-and-the-appeal-of-3d-printed-weapons (last visited Mar. 22, 2022); Chuck Goudie et al., Al Qaeda launches 1st public campaign in 4 years to encourage lone wolf terrorist attacks, ABC7 Chicago (July 29, 2021), available at https://abc7chicago.com/al-qaeda-terrorism-terrorist-attack-inspire-magazine/10918191 (last visited Mar. 22, 2022); Huder Abbasi, What's behind far-right trend of using 3D tech to make guns?, Aljazeera.com (July 31, 2021), available at https://www.aljazeera.com/news/2021/7/31/what-behind-far-right-trend-using-3d-tech-make-guns (last visited Mar. 22, 2022); Fergus Hunter, Alleged right-wing extremist charged over blueprint to 3D-print a gun, The Sydney Morning Herald (Sept. 13, 2021), available at https://www.smh.com.au/national/nsw/alleged-right-wing-extremist-arrested-over-blueprint-to-3d-print-a-gun-20210913-p58r80.html (last visited Mar. 22, 2022); Mexican National Charged with Possessing Firearms, Methamphetamine in Checked Luggage at MSP Airport, DOJ/OPA (Nov. 2, 2021), available at https://www.justice.gov/usao-mn/pr/mexican-national-charged-possessing-firearms-methamphetamine-checked-luggage-msp-airport. 24 See Cal. Penal Code. sec. 29180 (prohibiting ownership of firearms that do not bear a serial number or other mark of identification provided by the State); Conn. Gen. Stat. sec. 29-36a(a) (prohibiting manufacture of firearms without permanently affixing serial numbers issued by the State); Del. Code Ann. tit. 11 secs. 1459A, 1462 (prohibiting possession of an unfinished frame or receiver with no serial number and untraceable firearms); DC Code sec. 7-2504.08(a) (prohibiting licensees from selling firearms without serial numbers); Haw. Rev. Stat. sec. 134-10.2 (prohibiting unlicensed persons from producing, purchasing, or possessing 3D-printed or parts kit firearms without a serial number); Mass. Gen. Laws Ch. 269 sec. 11E (prohibiting manufacture or delivery of unserialized firearms to licensed dealer); N.J. Stat. Ann. sec. 2C:39-3(n) (prohibiting possession of firearms manufactured or assembled without serial number); N.Y. Penal Law secs. 265.50, 265.55 (prohibiting manufacture/possession of undetectable firearms); R.I. Gen. Laws sec. 11-47-8(e) (prohibiting possession of “a ghost gun or an undetectable firearm or any firearm produced by a 3D printing process”); Va. Code. Ann. sec. 18.2-308.5 (prohibiting possession of undetectable firearms); Wash. Rev. Code sec. 9.41.190 (prohibiting the manufacture with intent to sell of undetectable and untraceable firearms); see also Bill to ban ghost guns passes in Maryland House, heads to Gov. Hogan's desk, wjla.com (Mar. 29, 2022), available at https://wjla.com/news/local/ghost-guns-ban-bill-passes-maryland-house-maryland-governor-larry-hogan-signs-gun-control (last visited Apr. 3, 2022); Zenon Evans, Philadelphia Becomes First City To Ban 3D-Printed Gun Manufacturing, Reason.com (Nov. 22, 2013), available at https://reason.com/2013/11/22/philadelphia-becomes-first-city-to-ban-3 (last visited Mar. 22, 2022); Council unanimously approves Ghost Guns Bill, restricting the sale [or] transfer of ghost guns to minors, Montgomerycountymd.gov (Apr. 6, 2021), available at https://www2.montgomerycountymd.gov/mcgportalapps/Press_Detail.aspx?Item_ID=34040&Dept=1 (last visited Mar. 22, 2022); Chris Gros, Mayor Gloria signs ban on ghost guns in San Diego, CBS8 (Sept. 23, 2021), available at https://www.cbs8.com/article/news/local/mayor-gloria-signs-ban-on-ghost-guns-in-san-diego/509- ddd5f49d-29dc-42a6-8f2c-41f17381718f (last visited Mar. 22, 2022); Julia Wick, L.A. City Council votes to ban `ghost guns', Police1.com (Dec. 1, 2021), available at https://www.police1.com/gun-legislation-law-enforcement/articles/la-city-council-votes-to-ban-ghost-guns-8Rre0xK860ryrYud (last visited Mar. 22, 2022); Hannah Metzger, Denver outlaws owning, manufacturing `ghost guns' in city, denvergazette.com (Jan. 3, 2022), available at https://denvergazette.com/news/government/denver-outlaws-owning-manufacturing-ghost-guns-in-city/article_88799392-6d04-11ec-9da0-134e7e7be5f2.html (last visited Mar. 22, 2022); Jakob Rodgers, Oakland joins growing list of California cities to ban ghost guns, mercurynews.com (Jan. 18, 2022), available at https://www.mercurynews.com/2022/01/18/oakland-joins-growing-list-of-california-cities-to-ban-ghost-guns (last visited Mar. 22, 2022). Courts have recognized that the information licensees are required to record and maintain under the GCA “enable[s] federal authorities both to enforce the law's verification measures and to trace firearms used in crimes.” Abramski v. United States, 573 U.S. 169, 173 (2014) (citing H.R. Rep. No. 1577, 90th Cong., 2d Sess., 14 (1968)). At least one court has also concluded that ATF has a statutory duty pursuant to the GCA to trace firearms to keep them out of the hands of criminals and other prohibited persons. Blaustein & Reich, Inc. v. Buckles, 220 F. Supp. 2d 535, 537 (E.D. Va. 2002). This duty includes assisting State and local law enforcement in their efforts to control the traffic of firearms within their borders. 25 Indeed, as of January 2022, there are approximately 8,674 law enforcement agencies, including 49 agencies from 46 foreign countries, that use eTrace, a web-based application administered by ATF that allows authorized law enforcement agencies to submit and conduct comprehensive traces of recovered crime guns and develop long-term strategies on how best to reduce firearms-related crime, firearms trafficking, and violence in their communities. 26 25 See Public Law 90-351, sec. 901(a), 82 Stat. 212, 225-26 (1968); 18 U.S.C. 922(b)(2) (prohibiting licensees from selling or delivering any firearm to any person in a State where the purchase or possession by such person of such firearm would be in violation of any State law or published ordinance applicable at the place of sale, delivery, or other disposition); 18 U.S.C. 922(t)(2), (4) (NICS background check denied if receipt of firearm by transferee would violate State law); 18 U.S.C. 923(d)(1)(F) (requiring license applicants to certify compliance with the requirements of State and local law applicable to the conduct of business). 26 Fact Sheet, eTrace: Internet-Based Firearms Tracing and Analysis, ATF (Sept. 2021), available at https://www.atf.gov/resource-center/fact-sheet/fact-sheet-etrace-internet-based-firearms-tracing-and-analysis. As discussed in the NPRM, tracing is an integral tool for Federal, State, local, and international law enforcement agencies to utilize in their criminal investigations, and the proliferation of untraceable firearms severely undermines this process. 86 FR at 27724-25. The NPRM described the overall process that ATF engages in when tracing firearms submitted by law enforcement. Id. at 27724. The Department stressed how ATF relies on the recordkeeping required to be maintained by licensees in order to locate the first unlicensed person who acquired the recovered firearm from a licensed dealer. 27 This information can help find the perpetrator or provide valuable leads that help to solve the crime. Thus, for a successful trace to be conducted, an accurate firearm description is necessary and required to be recorded by a person licensed to engage in the business of manufacturing, importing, or dealing in firearms, or by a licensed collector of curio or relic firearms, regardless of whether it is a business or personal firearm of the licensee. 28 27 Licensees must respond to ATF trace requests within 24 hours. 18 U.S.C. 923(g)(7); see also J&G Sales Ltd. v. Truscott, 473 F.3d 1043, 1045-46 (9th Cir. 2007) (describing the tracing process). 28 See 18 U.S.C. 923(c); 27 CFR 478.125a(a)(4) (licensed manufacturers, importers, and dealers must record in a bound volume a complete description of firearms disposed of from their personal collections); 18 U.S.C. 923(g)(1)(A), (D); 27 CFR 478.125(e), (f) (licensed dealer and collector disposition records must contain a complete description of the firearm); 132 Cong. Rec. 15229 (1986) (Statement of Rep. Hughes) (“In order for the law enforcement Firearm Tracing Program to operate, some minimal level of recordkeeping is required [for sales from dealers' personal collections]. Otherwise, we will not have tracing capability. This provision simply requires that a bound volume be maintained by the dealer of the sales of firearms which would include a complete description of the firearm, including its manufacturer, model number, and its serial number and the verified name, address, and date of birth of the purchaser. This is only a minimal inconvenience for the dealer, yet obtaining and recording this information is critical to avoid serious damage to the Firearm Tracing Program.”). Because PMFs lack serial numbers and other markings from a licensed manufacturer, ATF has found it extremely difficult to successfully complete traces of PMFs. Out of the approximately 45,240 submitted traces of suspected PMFs mentioned above, ATF could only successfully complete approximately 445 of those attempted traces to an individual unlicensed purchaser. 29 Successful traces of PMFs have been completed in these rare instances primarily because licensees who acquired PMFs sometimes recorded a serial number that had been voluntarily engraved by the manufacturer on a commercially produced handgun slide, barrel, or another firearm part, which are not required by the GCA to be marked. 29 Source: ATF Office of Strategic Intelligence and Information. These numbers (as of January 21, 2022) include traces for both U.S. and international law enforcement agencies. In the NPRM, the Department noted that, with the rapid emergence of PMFs in recent years, licensees have sought clarity from ATF on how PMFs may be accepted and recorded. 86 FR at 27724-25. Licensees engaged in the business of dealing in firearms are subject to various recording and reporting requirements, including completion of a Firearms Acquisition and Disposition Record (“A&D Record”) to record their firearms inventory, 30 a Firearms Transaction Record, ATF Form 4473 (“Form 4473”), for disposition of a firearm to an unlicensed person, 31 a Federal Firearms Licensee Theft/Loss Report, ATF Form 3310.11, upon discovery of the theft or loss of firearms, 32 and a Report of Multiple Sale or Other Disposition of Pistols and Revolvers, ATF Form 3310.4, to document sales or other dispositions of multiple pistols or revolvers within five consecutive business days to the same person. 33 These forms require licensees to record the manufacturer and importer (if any), model (if designated), serial number, type, and caliber or gauge of the firearm. 30 27 CFR 478.125(e). 31 18 U.S.C. 923(g)(1)(A); 27 CFR 478.124. 32 18 U.S.C. 923(g)(6); 27 CFR 478.39a(b). 33 18 U.S.C. 923(g)(3)(A); 27 CFR 478.126a. Pursuant to 18 U.S.C. 923(g)(5)(A), licensed dealers along the Southwest U.S. border are also required by demand letter to report to ATF multiple sales of certain rifles during five consecutive business days to the same person on ATF Form 3310.12, including the rifle's serial number, manufacturer, importer, model, and caliber. Also under that statute, licensed dealers with 25 or more trace requests with a “time-to-crime” of three years or less must report to ATF the acquisition date, model, caliber or gauge, and the serial number of a secondhand firearm transferred by the dealer. As applied to PMFs, licensees acquiring them might only record a “type” of firearm ( e.g., pistol, revolver, rifle, or shotgun) in their A&D records and on Forms 4473. With such limited information, it will become increasingly difficult, if not impossible, for licensees and ATF (during inspections) to match accurately and reliably the PMFs in the firearms inventory with those recorded in required A&D records, or to determine whether the PMFs recorded as disposed on Forms 4473 are those recorded as disposed in the A&D records. 34 Likewise, licensees and ATF will have difficulty accurately determining which PMFs were stolen or lost from inventory. It will also be difficult for police to locate stolen PMFs in the business inventories of pawnbrokers, for example, 35 or to return any recovered stolen or lost PMFs to their rightful owners. 34 In United States v. Biswell, 406 U.S. 311, 315-16 (1972), the Supreme Court explained that “close scrutiny of [firearms] traffic is undeniably of central importance to federal efforts to prevent violent crime and to assist the States in regulating the firearms traffic within their borders. Large interests are at stake, and inspection is a crucial part of the regulatory scheme, since it assures that weapons are distributed through regular channels and in a traceable manner and makes possible the prevention of sales to undesirable customers and the detection of the origin of particular firearms” (citation omitted). 35 Most states require pawnbrokers to record or report any serial number and other identifying markings on pawned merchandise so that police can determine their origin. See Ala. Code sec. 5-19A-3(1); Alaska Stat. sec. 08.76.180(a)(4); Ariz. Rev. Stat. sec. 44-1625(C)(5); Colo. Rev. Stat. sec. 29-11.9-103(1); Conn. Gen. Stat. sec. 21-41(c); Del. Code Ann. tit. 24, sec. 2302(a)(1)(b); D.C. Code sec. 47-2884.11(d); Fla. Stat. sec. 538.04(1)(b)(3), (9); Ga. Code sec. 44-12-132(4); Haw. Rev. Stat. sec. 445-134.11(c)(10); 205 Ill. Comp. Stat. 510/5(a); Ind. Code sec. 28-7-5-19(a)(4); Ky. Rev. Stat. Ann. Sec. 226.040(1)(d)(7); La. Stat. Ann. sec. 37:1782(16)(a); Mass. Gen. Laws ch. 140 sec. 79; Mich. Comp. Laws sec. 446.205(5)(1), (4); Minn. Stat. sec. 325J.04(Sub.1)(1); Miss. Code Ann. sec. 75-67-305(1)(a)(iii), (ix); Mo. Rev. Stat. sec. 367.040(4)(6)(b); Neb. Rev. Stat. sec. 69-204(3); N.M. Stat. Ann. sec. 56-12-9(A)(3); N.C. Gen. Stat. sec. 66-391(b)(1); Ohio Rev. Code Ann. sec. 4727.07; Okla. Stat. tit. 59 sec. 1509(D)(h); S.C. Code Ann. sec. 40-39-80(B)(1)(l)(iii), (ix); Tenn. Code Ann. sec. 45-6-209(b)(1)(C), (H); Tex. Fin. Code Ann. sec. 371.157(4); Utah Code Ann. sec. 13-32a-104(1)(h)(i)(A); Va. Code Ann. sec. 54.1-4009(A)(1); Wash. Rev. Code sec. 19.60.020(1)(e); W. Va. Code sec. 47-26-2(b)(1); Wis. Stat. sec. 134.71(8)(c)(2). Assuming a PMF can be successfully traced to a Federal firearms licensee (“FFL”) or that a correct Form 4473 can be located, the NPRM explained that the ATF Form 4473 is the primary evidence used to prosecute straw purchasers who buy firearms from FFLs typically on behalf of prohibited persons, such as felons or illegal firearms traffickers, and other persons who could use the firearms to commit violent crimes. 36 The form is typically the key evidence that the straw purchaser who bought the firearm (and who can pass a background check) made a false statement to the FFL concerning the identity of the actual purchaser when acquiring that firearm, in violation of 18 U.S.C. 922(a)(6) and 924(a)(1)(A), or State law. 37 But as unmarked and difficult-to-trace PMFs are transacted throughout the commercial marketplace, law enforcement will have difficulties prosecuting straw purchasers for making false statements because it will be harder to prove that the firearms acquired under false pretenses on a Form 4473 were the ones found in the hands of the true purchaser. 38 Likewise, the absence of identifying firearm information on multiple sales forms and theft/loss reports makes it more difficult for ATF to identify firearms traffickers and thieves. 39 36 See United States v. Marzzarella, 614 F.3d 85, 100 (3d Cir. 2010) (“The direct tracing of the chain of custody of firearms involved in crimes is one useful means by which serial numbers assist law enforcement. But serial number tracing also provides agencies with vital criminology statistics—including a detailed picture of the geographical source areas for firearms trafficking and “time-to-crime” statistics which measure the time between a firearm's initial retail sale and its recovery in a crime—as well as allowing for the identification of individual dealers involved in the trafficking of firearms and the matching of ballistics data with recovered firearms” (footnotes omitted).); Following the Gun: Enforcing Federal Laws Against Firearms Traffickers, ATF at 1, 26 (2000) (serial number obliteration is a clear indicator of firearms trafficking to, among other criminals, armed narcotics traffickers). 37 See, e.g., Abramski v. United States, 573 U.S. 169, 192 (2014); Marshall v. Virginia, 822 SE2d 389, 392-93 (Va. Ct. App. 2019); Shirley v. Glass, 297 Kan. 888 (2013); Pennsylvania v. Baxter, 956 A.2d 465, 472 (Pa. Super. Ct. 2008). 38 See, e.g., United States v. Powell, 467 F. Supp. 3d 360, 368, 374 (E.D. Va. 2020) (indictment charging false statements on ATF Form 4473 in connection with the purchase of specific handguns listed by date of purchase, make, caliber, model, serial number, and name of FFL); United States v. McCurdy, 634 F. Supp. 2d 118, 121-22, 126 (D. Me. 2009) (denial of a motion for a new trial discussing whether the firearm sold as documented on the ATF Form 4473 and the firearm introduced at trial were the same). 39 The lack of firearm description information in theft/loss reports makes it difficult for ATF to match recovered firearms with those reported as lost or stolen, thereby hindering ATF's efforts to enforce the numerous provisions of the GCA that prohibit thefts. See 18 U.S.C. 922(i) (transporting or shipping stolen firearms in interstate or foreign commerce); 18 U.S.C. 922(j) (receiving, possessing, concealing, storing, bartering, selling, disposing, or pledging or accepting as security for a loan any stolen firearm which has moved in interstate or foreign commerce); 18 U.S.C. 922(u) (stealing a firearm that has been shipped or transported in interstate or foreign commerce from the person or premises of an FFL); 18 U.S.C. 924( l ) (stealing a firearm which is moving in or has moved in interstate commerce); 18 U.S.C. 924(m) (stealing a firearm from a licensee). C. Advanced Notice of Proposed Rulemaking on Identification Markings Placed on Firearm Silencers and Firearm Mufflers The NPRM noted that on May 4, 2016, the Department published an advance notice of proposed rulemaking (“ANPRM”) in the Federal Register . 86 FR 27728 n.50 (citing 81 FR 26764). The ANPRM was issued in response to a petition filed on behalf of the National Firearms Act Trade and Collectors Association (“NFATCA”), a trade group representing the firearms and import community. The petitioner requested that the relevant regulations be amended to require that a silencer be marked on the outer tube as opposed to other locations, such as an end cap that might be damaged when a projectile passes through it, unless a variance is granted by the Director on a case-by-case basis for good cause. ATF found that the petitioner raised valid concerns. Under the GCA, licensed manufacturers and importers must identify the frame or receiver of each firearm, including a firearm muffler or silencer, with a serial number in accordance with regulations. 18 U.S.C. 921(a)(3)(C), 923(i). The NFA requires firearm manufacturers, importers, and makers to identify each firearm, including a firearm muffler or silencer, with a serial number and such other identification as may be prescribed by regulations. 26 U.S.C. 5842(a), 5845(a)(7). Because the NFA defines each individual part of a firearm muffler or silencer as a “firearm” 40 that must be registered in the NFRTR, the regulations currently assume that every part defined as a silencer must be marked in order to be registered, and expressly require that each part be marked whenever sold, shipped, or otherwise disposed of even though it may have been installed by a qualified licensee within a complete muffler or silencer device. 41 40 A firearm “muffler or silencer” is defined to include “any combination of parts” designed and intended for the use in assembling or fabricating a firearm silencer or muffler and “any part intended only for use in such assembly or fabrication.” 18 U.S.C. 921(a)(24); 26 U.S.C. 5845(a)(7); 27 CFR 478.11, 479.11. This rule defines the term “complete muffler or silencer device” not to exempt individual silencer parts from the definition of firearm “muffler or silencer” subject to the requirements of the NFA, but to advise industry members when those individual silencer parts must be marked and registered in the NFRTR when they are used in assembling, fabricating, or repairing a muffler or silencer device. 41 See 27 CFR 479.101(b), 478.92(a)(4)(iii), 479.102(f)(1). The ANPRM explained that, along with industry members, ATF considers the term “outer tube” to mean the largest external part of a silencer and is that portion of a silencer that encapsulates all components of the silencing unit, and which contains and controls the expansion of the escaping gases. 81 FR at 26765. ATF explained that placing all required markings on the outer tube of a completed firearm silencer or firearm muffler is the accepted industry standard. In addition, ATF discussed that requiring identification markings to be placed on a single part provides consistency of markings throughout the industry and eliminates the need to re-mark a device in the event an end cap bearing the markings is damaged and requires replacement. ATF believed that a more specific marking requirement for firearm silencers, such as the outer tube, would lead to greater uniformity, improve public safety, and decrease firearms crimes, including firearms trafficking. See id. The ANPRM was used to solicit comments to determine if an amendment to the regulations that would require placement of identification markings on the outer tube of firearm silencers and mufflers was warranted. In response to the ANPRM, ATF received 48 comments. A few commenters supported issuance of a proposed rule because they believed it would not violate any constitutional rights under the Second Amendment, would enhance public safety for the reasons ATF stated, and would reduce confusion within the industry without being a financial burden because it is already a standard practice with many manufacturers. The majority of commenters expressed opposition and did not want ATF to proceed with any further rulemaking. Specific reasons for their objection to a proposed rule included a belief that: (1) ATF lacks legal authority to specify where markings on silencers must be located and that such a rule would violate the Second Amendment; (2) the initial NFATCA petition is outdated; (3) there is no data to support that a new rule would enhance public safety or reduce firearms trafficking; (4) a new regulation is unnecessary as the industry is already complying; (5) it is not feasible to comply with marking on the outer tube of the silencer with specific designs; (6) the proposed idea hinders technological advances and future designs; (7) it would create confusion and definitional problems because the definition of outer tube is outdated; and (8) the industry and public would incur financial burdens. Other commenters offered suggestions about outer tube replacement options especially because silencer tubes wear out over time. They suggested that a rule would be reasonable if ATF authorizes manufacturers to repair or replace damaged silencer tubes and engrave the new tube with the original serial number. Commenters also suggested alternative locations for silencer markings such as on end caps. They believed that markings should be placed on the major portion of the silencer, which could be the end cap or any section of the tube. They stressed that the outer tube is thin and there is a greater risk of burning through the metal when engraving and that end caps have greater thickness to work with when engraving. Based on further review and the comments received in response to the ANPRM, ATF incorporated a proposed definition of “frame or receiver” as it applies to firearm mufflers and silencers in the NPRM to clarify when and how silencer parts are to be marked and registered. 86 FR 27720. III. Notice of Proposed Rulemaking On May 21, 2021, the Department published in the Federal Register an NPRM entitled “Definition of `Frame or Receiver' and Identification of Firearms,” 86 FR 27720, proposing changes to various regulations in 27 CFR parts 447, 478, and 479. Overall, the NPRM proposed amending ATF's regulations to clarify the definition of “firearm” and to provide a more comprehensive definition of “frame or receiver” so that these terms more accurately reflect how most modern-day firearms are produced and function, and so that the courts, the firearms industry, and the public at large would no longer misinterpret the term to mean that most firearms in circulation have no parts identifiable as a frame or receiver. The NPRM also proposed new terms and definitions to account for technological developments and modern terminology in the firearms industry, as well as proposed amendments to the marking and recordkeeping requirements that would be necessary to implement these definitions. A. Definition of “Firearm” In the NPRM, the Department proposed adding a sentence at the end of the definition of “firearm” in 27 CFR 478.11 to reflect existing case law, providing that “[t]he term shall include a weapon parts kit that is designed to or may readily be assembled, completed, converted, or restored to expel a projectile by the action of an explosive.” However, the proposed amendment was not intended to affect the classification of a weapon, including a weapon parts kit, in which the frame or receiver (as defined in the proposed rule) of such weapon is properly destroyed. See 86 FR at 27726, 27729-30. Therefore, another sentence was proposed to be added at the end of the definition of “firearm” to provide that “[t]he term shall not include a weapon, including a weapon parts kit, in which each part defined as a frame or receiver of such weapon is destroyed.” Id. at 27726. The Department explained in the NPRM that “firearm” as defined under the GCA, 18 U.S.C. 921(a)(3) and 27 CFR 478.11, includes inoperable weapons even though they will not expel a projectile by the action of an explosive at the time of sale or distribution if they are “ designed to ” 42 or “ may readily be converted ” 43 to expel a projectile by the action of an explosive. Weapon parts kits, or aggregations of weapon parts, some of which contain all of the components necessary to complete a functional weapon within a short period of time, have been increasingly sold to individuals either directly from manufacturers of the kits or retailers, without background checks or recordkeeping. 86 FR at 27726. Some of these firearm kits include jigs, templates, and tools that allow the purchaser to complete the weapon fairly or reasonably efficiently, quickly, and easily to a functional state. Such weapon parts kits or aggregations of weapon parts that are designed to or may readily be converted to expel a projectile by the action of an explosive are also “firearms” under 18 U.S.C. 921(a)(3)(A). 44 This proposed addition makes explicit that manufacturers and sellers of such kits or aggregations of weapon parts are subject to the same regulatory requirements applicable to the manufacture or sale of fully completed and assembled firearms. See 86 FR at 27726. 42 Numerous courts have held that weapons designed to expel a projectile by the action of an explosive are “firearms” under 18 U.S.C. 921(a)(3)(A) even if they cannot expel a projectile in their present form or configuration. See, e.g., United States v. Hardin, 889 F.3d 945, 946-47, 949 (8th Cir. 2018) (pistol with broken trigger and numerous missing internal parts was a weapon designed to expel a projectile by the action of an explosive); United States v. Dotson, 712 F.3d 369, 370-71 (7th Cir. 2013) (saying, in ruling that a pistol with corroded, missing, and broken components was a “firearm,” that “[a]n airplane is designed to fly; a defect in manufacture or maintenance that prevents it from flying does not alter its design”); United States v. Davis, 668 F.3d 576, 577 (8th Cir. 2012) (holding that a pistol with no trigger was a “firearm” within the meaning of section 2K2.1(a)(3)(A)(i) of the Sentencing Guidelines and applying “the same reasoning [that courts have applied in section 921(a)(3) cases] to Guidelines provisions that incorporate the § 921(a)(3) definition”); United States v. Counce, 445 F.3d 1016, 1018 (8th Cir. 2006) (handgun with missing safety); United States v. Rivera, 415 F.3d 284, 285-87 (2d Cir. 2005) (pistol with a broken firing pin and flattened firing-pin channel); United States v. Morales, 280 F. Supp. 2d 262, 272-73 (S.D.N.Y. 2003) (partially disassembled Tec-9 pistol was designed to expel a projectile); United States v. Adams, 137 F.3d 1298, 1300 & n.2 (11th Cir. 1998) (potentially inoperable shotgun); United States. v. Brown, 117 F.3d 353 (7th Cir. 1997) (holding that a gun with no firing pin was a “firearm” within the meaning of section 2B3.1(b)(2)(C) of the Sentencing Guidelines, and discussing analogous cases interpreting section 921(a)(3)(A)); United States v. Reed, 114 F.3d 1053 (10th Cir. 1997) (shotgun with broken breech bolt); United States v. Hunter, 101 F.3d 82 (9th Cir. 1996) (holding that the sentence enhancement for use of a semiautomatic weapon in section 924(c) applied to a pistol with broken firing pin); United States v. Yannott, 42 F.3d 999, 1005-07 (6th Cir. 1994) (shotgun with broken firing pin); United States v. Ruiz, 986 F.2d 905, 910 (5th Cir. 1993) (revolver with hammer filed down); United States v. York, 830 F.2d 885, 891 (8th Cir. 1987) (revolver with no firing pin and cylinder did not line up with barrel); United States v. Thomas, No. 17-194 (RDM), 2019 WL 4095569, at *4 (D.D.C. Aug. 29, 2019) (in ruling that a revolver missing its hammer, hammer screw, trigger, cylinder stop, hand, ejector rod housing, base pin, screw, nut, spring, loading gate detent and spring and miscellaneous screws was a “firearm,” the court said: “[t]he Titanic was, after all, `designed' to be unsinkable”). But see Dotson, 712 F.3d at 371 (a Beretta pistol redesigned to be a cigarette lighter); Rivera, 415 F.3d at 286-87 (“[A] gun with a barrel filled with lead, maybe for use as a theatrical prop, might perhaps no longer be deemed `designed to' or `readily be converted' to fire a bullet.”); United States v. Wada, 323 F. Supp. 2d 1079 (D. Or. 2004) (firearms redesigned as ornaments that “would take a great deal of time, expertise, equipment, and materials to attempt to reactivate” were no longer designed to expel a projectile by the action of an explosive, and could not readily be converted to do so). 43 See, e.g., United States v. Mullins, 446 F.3d 750, 756 (8th Cir. 2006) (starter gun that can be modified in less than one hour by a person without any specialized knowledge to fire may be considered “readily convertible” under the GCA); United States v. 16,179 Molso Italian .22 Caliber Winlee Derringer Convertible Starter Guns, 443 F.2d 463 (2d Cir. 1971) (starter guns converted in no more than 12 minutes to fire live ammunition were readily convertible under the GCA); United States v. Morales, 280 F. Supp. 2d 262, 272-73 (S.D.N.Y. 2003) (partially disassembled Tec-9 pistol that could be assembled within a short period of time could readily be converted to expel a projectile). Cf. United States v. Dodson, 519 F. App'x 344, 352-53 (6th Cir. 2013) (gun that was restored with 90 minutes of work, using widely available parts and equipment and common welding techniques, fit comfortably within the readily restorable standard of 26 U.S.C. 5845(b)); United States v. TRW Rifle 7.62×51mm Caliber, One Model 14 Serial 593006, 447 F.3d 686, 692 (9th Cir. 2006) (a two-hour restoration process using ordinary tools, including a stick weld, is within the ordinary meaning of “readily restored”); United States v. One TRW, Model M14, 7.62 Caliber Rifle, 441 F.3d 416, 422-24 (6th Cir. 2006) (“[T]he Defendant weapon here had all of the necessary parts for restoration and would take no more than six hours to restore.”); United States v. Woods, 560 F.2d 660, 664 (5th Cir. 1977) (holding that a weapon was a shotgun within the meaning of 26 U.S.C. 5845(d) and stating “[t]he fact that the weapon was in two pieces when found is immaterial considering that only a minimum of effort was required to make it operable.”); United States v. Smith, 477 F.2d 399, 400-01 (8th Cir. 1973) (machinegun that would take around an eight-hour working day in a properly equipped machine shop was readily restored to shoot); United States v. Catanzaro, 368 F. Supp. 450, 453 (D. Conn. 1973) (a sawed-off shotgun was “readily restorable to fire” where it could be reassembled in one hour and the necessary missing parts could be obtained at a Smith & Wesson plant). But see United States v. Seven Miscellaneous Firearms, 503 F. Supp. 565, 574-75 (D.D.C. 1980) (weapons could not be “readily restored to fire” when restoration required master gunsmith in a gun shop and $65,000 worth of equipment and tools). 44 See, e.g., United States v. Wick, 697 F. App'x 507, 508 (9th Cir. 2017) (complete UZI parts kits “could `readily be converted to expel a projectile by the action of an explosive,' meeting the statute's definition of firearm under § 921(a)(3)(A)” because the “kits contained all of the necessary components to assemble a fully functioning firearm with relative ease”); United States v. Stewart, 451 F.3d 1071, 1072-73, 1073 n.2 (9th Cir. 2006) (upholding district court's finding that .50 caliber rifle kits with incomplete receivers were “firearms” under section 921(a)(3)(A) because they could easily be converted to expel a projectile); United States v. Theodoropoulos, 866 F.2d 587, 595 n.3 (3d Cir. 1989), overruled in part on other grounds by United States v. Price, 76 F.3d 526, 528 (3d Cir. 1996) (disassembled machine pistol that that could easily be made operable was a firearm under section 921(a)(3)(A)); United States v. Morales, 280 F. Supp. 2d 262, 272-73 (S.D.N.Y. 2003) (partially disassembled Tec-9 pistol that could be assembled within short period of time could readily be converted to expel a projectile was a firearm under section 921(a)(3)(A)); United States v. Randolph, No. 02 CR. 850-01 (RWS), 2003 WL 1461610, at *2 (S.D.N.Y. Mar. 20, 2003) (gun consisting of “disassembled parts with no ammunition, no magazine, and a broken firing pin, making it incapable of being fired without replacement or repair” was a “firearm” under section 921(a)(3)(A) because it could be readily converted to expel a projectile and included the frame or receiver of such a weapon); cf. United States v. Annis, 446 F.3d 852, 857 (8th Cir. 2006) (partially disassembled rifle that could easily be made operational was a firearm under sentencing guidelines); United States v. Ryles, 988 F.2d 13, 16 (5th Cir. 1993) (same with disassembled shotgun that could have been readily converted to an operable firearm); Enamorado v. United States, No. C16-3029-MWB, 2017 WL 2588428, at *6 (N.D. Iowa June 14, 2017) (same with disassembled .45 caliber handgun that could easily be reassembled). B. Definition of “Frame or Receiver” The Department proposed to revise the definition of “frame or receiver” with a multi-part definition. First proposed was a general definition of “frame or receiver” with nonexclusive examples that illustrated the definition. This was followed by four proposed supplements, described below, that further explained the meaning of the term “frame or receiver” for certain firearm designs and configurations. Although the proposed definition was intended to more broadly define the term “frame or receiver” than the current definition, it was not intended to alter any prior determinations by ATF regarding which specific part of a given weapon it considered the frame or receiver. The NPRM also proposed to codify in the regulations the factors ATF considers when classifying the frame or receiver of a firearm. 1. General Definition of “Frame or Receiver” As a threshold matter, the NPRM proposed that the new definition, with a partial exception for an internal frame or chassis, make clear that each frame or receiver be visible to the exterior when the complete weapon is assembled so that licensees and law enforcement can quickly and easily identify the markings. Next, the NPRM proposed defining the term “frame or receiver” more broadly as a part that provides housing or a structure designed to hold or integrate any fire control component, which would have included, at a minimum, any housing or holding structure for a hammer, bolt, bolt carrier, breechblock, cylinder, trigger mechanism, firing pin, striker, or slide rails. However, the proposed definition would not have been limited to those particular fire control components 45 and was proposed to be general enough to encompass changes in technology and parts terminology. For further clarity, four nonexclusive examples with illustrations of common single-framed firearms were provided. See 86 FR at 27727, 27742. Finally, the proposed definition stated that persons who may acquire or possess a part now defined as a frame or receiver that is identified with a serial number must presume, absent an official determination by ATF or other reliable evidence to the contrary, that the part is a firearm frame or receiver without further guidance. 45 The prefatory paragraph to the definitional sections in the GCA and NFA regulations explain that “[t]he terms `includes' and `including' do not exclude other things not enumerated which are in the same general class or are otherwise within the scope thereof.” 27 CFR 478.11, 479.11. 2. Definition of “Firearm Muffler or Silencer Frame or Receiver” The first proposed supplement to define the term “frame or receiver” as it applies to a “firearm muffler or silencer frame or receiver” and to add a new term “complete muffler or silencer device” is further discussed in Section III.D of this preamble. The NPRM proposed that in the case of a firearm muffler or firearm silencer, the frame or receiver is a part of the firearm that is visible from the exterior of a completed device and provides a housing or a structure designed to hold or integrate one or more essential internal components of the device. As described in Section II.C of this preamble, the GCA's marking requirement and the GCA/NFA's definition of firearm “muffler or silencer” (sometimes referred to as a “sound suppressor”) and its marking requirements have caused confusion and concern among many silencer manufacturers over the years. The NPRM explained that some silencer parts defined as “silencers,” such as baffles, are difficult for manufacturers to mark and listed examples of the ATF forms that manufacturers would have difficulty filing and processing in a timely manner. 86 FR at 27728. The Department also explained that it makes little sense to mark all silencer parts for tracing purposes when the outer tube or housing of the complete device is marked and registered. Id. at 27727-28. For these reasons, the new definitions were proposed to clarify for manufacturers and makers of complete muffler or silencer devices that they need only mark the one part of the device defined as the frame or receiver under the proposed rule. However, individual muffler or silencer parts were proposed to be marked if they are disposed of separately from a complete device unless transferred by manufacturers qualified under the NFA to other qualified licensees for the manufacture or repair of complete devices. 46 46 This rule is consistent with ATF enforcement policy. See footnote 58, infra. 3. Definition of “Split or Modular Frame or Receiver” The second proposed supplement to the general definition sought to capture the majority of firearms that now use a split design as discussed above. It sought to clarify that even though a firearm, including a silencer, may have more than one part that falls within the definition of “frame or receiver,” ATF may classify a specific part or parts to be the “frame or receiver” of a particular weapon. It then set forth the various factors ATF would consider in making this determination with no single factor controlling. See 86 FR at 27728-29, 27743. It also proposed the clarification that “[f]rames or receivers of different weapons that are combined to create a similar weapon each retain their respective classifications as frames or receivers provided they retain their original design and configuration.” Id. at 27734. To ensure that the proposed definition of “split or modular frame or receiver” did not affect existing ATF classifications that specified a single component as the frame or receiver, the definition included a nonexclusive list of common weapons with a split or modular frame or receiver configuration for which ATF previously determined a specific part to be the frame or receiver. See id. at 27729, 27743-46. The NPRM explained that a manufacturer or importer of one of these firearm designs, as they would exist as of the final rule's date of publication, could refer to this list to know which part is the frame or receiver, thereby allowing the manufacturer or importer to mark a single part without seeking a determination from ATF. However, if there was to be a present or future split or modular design for a firearm that was not comparable to an existing classification, then the proposed definition of “frame or receiver” would advise, absent a variance or classification from ATF, that more than one part is the frame or receiver subject to marking and other requirements. 4. Definition of “Partially Complete, Disassembled, or Inoperable Frame or Receiver” The third supplement proposed to define “frame or receiver” as including frames or receivers that are partially complete, disassembled, or inoperable, or a frame or receiver that has reached a stage in manufacture where it may readily be completed, assembled, converted, or restored to a functional state. The NPRM stated that, to determine this status, “the Director may consider any available instructions, guides, templates, jigs, equipment, tools, or marketing materials.” 86 FR at 27729, 27746. “Partially complete,” for purposes of this definition, was proposed to mean a forging, casting, printing, extrusion, machined body, or similar article at a stage in manufacture where it is clearly identifiable as an unfinished component part of a weapon. The NPRM explained that this supplemental definition aimed to address when an object becomes a frame or receiver such that it is a regulated article. The NPRM stated that partially complete or unassembled frames or receivers, commonly called “80% receivers,” 47 are often sold in kits where the frame or receiver can readily be completed or assembled to a functional state. See id. at 27729 n.54. The Department stated that the supplemental definition is necessary for clarity because companies are not running background checks or maintaining transaction records when they manufacture and sell these kits. Accordingly, prohibited persons have easily obtained them 48 and, when recovered, they are nearly impossible to trace. The proposed definition also sought to make clear that unformed blocks of metal, and other similar articles only in a primordial state 49 would not—without more processing—be considered a “partially complete” frame or receiver that is captured under the definition of “frame or receiver.” 47 The term “80% receiver” is a term used by some industry members, the public, and the media to describe a frame or receiver that has not yet reached a stage of manufacture to be classified as a “frame or receiver” under Federal law. However, that term is neither found in Federal law nor accepted by ATF. 48 See 86 FR at 27729 n.55; see also Gene Johnson, Felon on supervision accused of having `ghost gun' arsenal, Associated Press (Feb. 28, 2020), available at https://apnews.com/article/cc61d48e83a2c8113cdb1e1ed6fe6006 (last visited Mar. 23, 2022); Sarah Cassi, Lehigh Valley felon was using 3D printer to make `ghost guns' at home, Pa. attorney general says,LehighValleyLive.com (June 29, 2021), available at https://www.lehighvalleylive.com/northampton-county/2021/06/lehigh-valley-felon-was-using-3d-printer-to-make-ghost-guns-at-home-pa-attorney-general-says.html (last visited Mar. 23, 2022); Deputy recovers `ghost gun' from convicted felon during traffic stop, Fontana Herald News (Aug. 10, 2021), available at https://www.fontanaheraldnews.com/news/inland_empire_news/deputy-recovers-ghost-gun-from-convicted-felon-during-traffic-stop/article_3cfe0fd0-f4a3-11eb-bd31-03979dc83307.html (last visited Mar. 23, 2022); Parolee Arrested With AR-15 Ghost Gun, Fake Law Enforcement Badge, NBC Palm Springs (Aug. 13, 2021), available at https://nbcpalmsprings.com/2021/08/13/parolee-arrested-with-ar-15-ghost-gun-fake-law-enforcement-badge (last visited Mar. 23, 2022); Georgetown Arrest of a Felon Leads to Recovery of Ghost Gun, Seattle Police Department (Nov. 8, 2021), available at https://spdblotter.seattle.gov/2021/11/08/georgetown-arrest-of-a-felon-leads-to-recovery-of-ghost-gun (last visited Mar. 23, 2022). 49 As used in this rule, the term “primordial” refers to an item, such as an unmachined block of metal, liquid polymer, or other raw material that is in its original natural form or at an early stage of development without substantial processing. See Primordial, Oxford English Dictionary, available at https://www.oed.com/view/Entry/151373?redirectedFrom=primordial#eid (last visited Mar. 23, 2022) (“that [which] constitutes the origin or starting point from which something else is derived or developed”). 5. Definition of “Destroyed Frame or Receiver” The fourth supplement proposed to exclude from the definition of “frame or receiver” any frame or receiver that has been destroyed. This proposed definition described a destroyed frame or receiver as one permanently altered not to provide housing or a structure that may hold or integrate any fire control or essential internal component, and that may not readily be assembled, completed, converted, or restored to a functional state. The proposed definition set forth nonexclusive acceptable methods of destruction, which had been provided by ATF in its past guidance. 50 50 See 86 FR at 27729, 27746. C. Definition of “Readily” The Department proposed to add the term “readily” to 27 CFR 478.11 and 479.11 and define it as “a process that is fairly or reasonably efficient, quick, and easy, but not necessarily the most efficient, speedy, or easy process.” 86 FR at 27730, 27747, 27751. It further listed factors relevant in applying this proposed definition, such as time, ease, expertise, equipment, availability, expense, scope, and feasibility, with brief examples describing these factors. Id. The proposed definitions and factors are based on case law interpreting “may readily be converted to expel a projectile” in 18 U.S.C. 921(a)(3)(A) and “can be readily restored to shoot” in 26 U.S.C. 5845(b)-(d). See id. at 27730 & n.58. The NPRM explained that defining the term “readily” was necessary to determine when a weapon, including a weapon parts kit, a partially complete or damaged frame or receiver, or an aggregation of weapon parts becomes a “firearm” regulated under the GCA and NFA. D. Definitions of “Complete Weapon” and “Complete Muffler or Silencer Device” The Department proposed to add the terms “complete weapon” and “complete muffler or silencer device” to 27 CFR 478.11 and 479.11. The proposed definition of a “complete weapon” was a firearm, whether or not assembled or operable, containing all component parts necessary to function as designed but not a firearm muffler or silencer device. 86 FR at 27730. The proposed definition of a “complete muffler or silencer device” was a firearm muffler or firearm silencer, whether or not assembled or operable, containing all of the component parts necessary to function as designed. Id. These terms were proposed to explain when a frame or receiver of a firearm, including a firearm muffler or silencer, as the case may be, must be marked for identification. E. Definition of “Privately Made Firearm” The NPRM proposed adding the term “privately made firearm” to 27 CFR 478.11 and to define it as a firearm, including a frame or receiver, assembled by a person other than a licensed manufacturer, and not containing a serial number or other identifying marking placed by a licensed manufacturer at the time the firearm was produced. See 86 FR at 27730. The term would not include a firearm identified and registered in the NFRTR pursuant to 26 U.S.C., chapter 53, or any firearm made before October 22, 1968 (unless remanufactured after that date). 51 51 The Federal Firearms Act of 1938 (repealed), the predecessor to the GCA, made it unlawful for a person to receive in interstate or foreign commerce a firearm that had the manufacturer's serial number removed, obliterated, or altered. 15 U.S.C. 902(i) (1940). Regulations promulgated to implement this law required each firearm manufactured after July 1, 1958, to be identified with the name of the manufacturer or importer, a serial number, caliber, and model. However, there was an exception from the serial number and model requirements for any shotgun or .22 caliber rifle unless that firearm was also subject to the NFA. 26 CFR 177.50 (1959) (rescinded). F. Definition of “Importer's or Manufacturer's Serial Number” The Department proposed to add the term “importer's or manufacturer's serial number” in 27 CFR 478.11 and to define it as the identification number, licensee name, licensee city or State, or license number placed by a licensee on a firearm frame or receiver or on a PMF. The NPRM explained that a serial number incorporating the abbreviated FFL number (also known in industry as the “RDS key”) placed by a licensee on a PMF under the proposed rule met the definition of the “importer's or manufacturer's serial number.” The Department also explained that the proposed definition would help ensure that the serial numbers and other markings necessary to ensure tracing are considered the “importer's or manufacturer's serial number” protected by 18 U.S.C. 922(k) and numerous State laws, which prohibit possession of firearms with serial numbers that have been removed, obliterated, or altered. See 86 FR at 27730 n.62. G. Definition of “Gunsmith” 52 52 The term “gunsmith” is not used in the GCA; however, the Firearm Owners' Protection Act, Public Law 99-308 (1986), amended the GCA to define “engaged in the business” as applied to dealers to clarify when gunsmiths must have a license. See 18 U.S.C. 921(a)(11)(B), (a)(21)(D); 132 Cong. Rec. 9603-04 (1986) (statement of Sen. McClure). The Department proposed to amend the definition of “engaged in the business” as it applies to a “gunsmith” in 27 CFR 478.11 to clarify that businesses may be licensed as dealer-gunsmiths rather than as manufacturers if they routinely repair or customize existing firearms, make or fit special barrels, stocks, or trigger mechanisms, or mark firearms as a service performed on firearms not for sale or distribution by a licensee. 53 The proposed amendment was also for the purpose of providing greater access to professional marking services so that persons who engage in the business of identifying firearms for nonlicensees may become licensed as dealer-gunsmiths solely to provide professional PMF marking services. 53 This rule would supersede ATF Ruling 2010-10, which allows gunsmiths under specified conditions to engage in certain manufacturing activities for licensed manufacturers. This change was proposed to eliminate a significant source of confusion among regulated industry members and the public as to who needs a license to manufacture firearms. See Broughman v. Carver, 624 F.3d 670 (4th Cir. 2010) (distinguishing dealer-gunsmiths from manufacturers). H. Marking Requirements for Firearms 1. Information Required to be Marked on the “Frame or Receiver” To properly implement the new definitions, the Department proposed to amend 27 CFR 478.92(a) and 479.102 to explain how and when markings must be applied on each part defined as a frame or receiver, particularly since there could have been more than one part of a complete weapon, or complete muffler or silencer device, which is the frame or receiver ( i.e., when ATF has not identified specific part(s) as the frame or receiver). Under the NPRM, each frame or receiver of a new firearm design or configuration manufactured or imported after the publication of the final rule was proposed to be marked with a serial number, and either : (a) The manufacturer's or importer's name (or recognized abbreviation), and city and State (or recognized abbreviation) where the manufacturer or importer maintains their place of business, or in the case of a maker of an NFA firearm, where the firearm was made; or (b) the manufacturer's or importer's name (or recognized abbreviation), and the serial number beginning with the licensee's abbreviated FFL number as a prefix, which is the first three and last five digits, followed by a hyphen, and then followed by a number (which may incorporate letters and a hyphen) as a suffix, e.g., “12345678-[number].” The serial number (with or without the FFL prefix) identified on each part of a weapon defined as a frame or receiver was proposed to be the same number, but could not duplicate any serial number(s) placed by the licensee on any other firearm. The NPRM proposed that licensed manufacturers and importers could continue to identify the additional information on firearms (other than PMFs) of the same design and configuration as they existed before the effective date of the final rule under the prior content rules, and any rules necessary to ensure such identification would have remained effective for that purpose. This proposed provision was intended to make the transition easier and reduce production costs incurred by licensees. Except for silencer parts transferred by manufacturers to other qualified manufacturers and dealers for completion or repair of devices, no change was proposed to the existing requirement that each part defined as a machinegun or silencer that is disposed of separately and not part of a complete weapon or device be marked with all required information, because individual machinegun conversion and silencer parts are “firearms” under the NFA that must be registered in the NFRTR. 26 U.S.C. 5841(a)(1), 5845(a), (b). However, for frames and receivers, and individual machinegun conversion or silencer parts defined as “firearms” that are disposed of separately, the proposed rule allowed the model designation and caliber or gauge to be omitted if it is unknown at the time the part is identified. See 86 FR at 27731. 2. Size and Depth of Markings The Department did not propose changes to the existing requirements for size and depth of markings in 27 CFR 478.92(a)(1) and 479.102(a), but for sake of clarity, proposed to consolidate them into a standalone paragraph. 3. Period of Time To Identify Firearms The Department proposed to identify the point at which manufacturers would be required to place markings on firearms. The NPRM proposed that complete weapons or complete muffler or silencer devices, as defined in the rule, would be allowed to be marked up to seven days from completion of the active manufacturing process for the weapon or device, or prior to disposition, whichever is sooner. Except for silencer parts produced by qualified manufacturers for transfer to other licensees to complete or repair silencer devices, parts defined as a frame or receiver, machinegun, or firearm muffler or firearm silencer that are not component parts of a complete weapon or device when disposed of would be allowed to be marked up to seven days following the date of completion of the active manufacturing process for the part, or prior to disposition, whichever is sooner. Adding this proposed language would codify ATF Ruling 2012-1, which explained that, whether the end product is to become a complete weapon or device, or a frame or receiver to be disposed of separately, it is reasonable for a licensed manufacturer to have seven days following the date of completion of the entire manufacturing process in which to mark a firearm manufactured and record its identifying information in the manufacturer's permanent records. 4. Marking of “Privately Made Firearms” The Department proposed to amend 27 CFR 478.92 to require FFLs to mark, or supervise the marking of, the same serial number on each part of the weapon defined as frame or receiver (as defined in the rule) of a PMF that the licensee acquired, but not duplicate any serial number(s) placed on any other firearm. The marking would begin with the FFL's abbreviated license number (first three and last five digits) as a prefix, followed by a hyphen, and then followed by a number as a suffix ( e.g., “12345678-[number]”). Unless previously identified by another licensee, PMFs acquired by licensees on or after the effective date of the rule were proposed to be marked in this manner within seven days of receipt or other acquisition (including from a personal collection), or before the date of disposition (including to a personal collection), whichever is sooner. 54 For PMFs acquired by licensees before the effective date of the rule, the proposed rule would require licensees to mark or cause them to be marked by another licensee either within 60 days from the effective date of a final rule, or before the date of final disposition (including to a personal collection), whichever is sooner. 55 54 Under this rule, licensed collectors would only need to mark PMFs they receive that are defined as “curios or relics.” See 27 CFR 478.11 (definitions of “firearm” and “curios or relics”). 55 Handguns that are 3D-printed are also subject to the registration and taxation requirements of the NFA if they have a smooth bore and are capable of being concealed on the person, thereby falling within the definition of “any other weapon” under the NFA. See 26 U.S.C. 5845(e). Consistent with the language and purpose of the GCA, the NPRM explained that this proposed provision was necessary to allow ATF to trace all firearms acquired and disposed of by licensees, prevent illicit firearms trafficking, and provide procedures for FFLs and the public to follow with respect to PMF transactions with the licensed community. The proposed rule further noted that this provision was crucial in light of advances in technology that allow unlicensed, including prohibited, persons easily and repeatedly to produce firearms at home from parts ordered online, or by using 3D printers or personally owned or leased equipment. Such privately made firearms have made and will continue to make their way to the primary market in firearms through the licensed community. 56 56 Under Federal law, for example, certain firearm transactions must be conducted through FFLs. See 18 U.S.C. 922(a)(5) (prohibiting any person other than a licensee, subject to certain limited exceptions, from selling or delivering a firearm to an unlicensed out-of-state resident). At the same time, nothing in the proposed rule restricted persons who are not otherwise prohibited from possessing firearms from making their own firearms without markings solely for personal use, nor did the proposed rule require individuals to mark PMFs when they occasionally acquire them for a personal collection, or sell or transfer them from a personal collection to unlicensed in-State residents in accordance with Federal, State, and local law. Further, the NPRM would not require FFLs to accept any PMFs, or to mark PMFs themselves, or to provide services to place identification marks on PMFs. Licensees would be able to arrange for individuals who wish to transfer PMFs to licensees to have them marked by another licensee before accepting them, provided they are properly marked in accordance with the proposed rule. 5. Meaning of Marking Terms An additional amendment to 27 CFR 478.92 and 478.102 was proposed to clarify the meaning of the terms “legible” and “legibly” to ensure that “the identification markings use exclusively Roman letters ( e.g., A, a, B, b, C, c) and Arabic numerals ( e.g., 1, 2, 3), or solely Arabic numerals, and may include a hyphen,” and that the terms “conspicuous” and “conspicuously” are understood to mean that the identification markings are capable of being easily seen and unobstructed by other markings when the firearm is assembled. 86 FR at 27733. These would clarify the meaning of those terms as explained in ATF Ruling 2002-6 (“legible”), and ATF's final rule at 66 FR 40599 (Aug. 3, 2001) (referencing U.S. Customs Service regulations on the definition of “conspicuous”). 6. Alternate Means or Period of Identification The proposed rule would not alter the Director's existing ability to authorize other means of identification, or a “marking variance,” for any part defined as a firearm (including a machinegun or a silencer), or the process for such a variance. 7. Destructive Device Period of Identification The proposed rule specified a seven-day grace period in which to mark all completed firearms, including destructive devices (similar to other firearms), and would have allowed ATF to grant a variance from this period. There were no proposed changes to the marking requirements for destructive devices. 8. Adoption of Identifying Markings The Department proposed allowing licensed manufacturers and importers to adopt an existing serial number, caliber/gauge, model, or other markings already identified on a firearm, provided that they legibly and conspicuously place, or cause to be placed, on each part (or part(s)) defined as a frame or receiver, either the FFL's name (or recognized abbreviation), and city and State (or recognized abbreviation) where they maintain their place of business; or their name (or recognized abbreviation) and their abbreviated FFL number, as described in Section III.H.1 of this preamble, followed by the existing serial number (including any other abbreviated FFL prefix) as a suffix, e.g., “12345678-[serial number],” to ensure the traceability of the firearm. This language was proposed to supersede ATF Ruling 2013-3 as it applied to licensed manufacturers and importers. The proposal was aimed at avoiding multiple markings on firearms that could be confusing to law enforcement and alleviate concerns of some manufacturers and importers regarding serial number duplication when firearms are remanufactured or imported. 9. Firearm Muffler or Silencer Parts Transferred Between Qualified Licensees Licensed and qualified firearm muffler or silencer manufacturers routinely transfer small internal muffler or silencer components to each other to produce complete devices. Licensees qualified under the NFA routinely do the same when repairing existing devices. Because of the difficulties and expense of marking and registering small individual components used to commercially manufacture a complete muffler or silencer device with little public safety benefit, the NPRM proposed to allow qualified manufacturers to transfer parts defined as a firearm muffler or silencer to other qualified manufacturers without immediately identifying or registering them. Once the new device was completed with the part, the manufacturer would be required to identify and register the device in the manner and within the period specified in the proposed rule for a complete device. Likewise, the NPRM proposed to allow qualified manufacturers to transfer muffler or silencer replacement parts to qualified manufacturers and dealers to repair existing devices already identified and registered in the NFRTR. Furt [Text truncated at 120,000 characters. The full text is on the page linked above.] --- Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/fr%3A2022-08026. Public record. Not legal advice.