Bondi v. Vanderstok (604 U.S. 458, 2025)

PRELIMINARY PRINT Volume 604 U. S. Part 2 Pages 458–517 OFFICIAL REPORTS OF THE SUPREME COURT March 26, 2025 Page Proof Pending Publication REBECCA A. WOMELDORF reporter of decisions NOTICE: This preliminary print is subject to formal revision before the bound volume is published. Users are requested to notify the Reporter of Decisions, Supreme Court of the United States, Washington, D. C. 20543, pio@supremecourt.gov, of any typographical or other formal errors. 458 OCTOBER TERM, 2024 Syllabus BONDI, ATTORNEY GENERAL, et al. v. VANDERSTOK et al. certiorari to the united states court of appeals for the fth circuit No. 23–852. Argued October 8, 2024—Decided March 26, 2025 The Gun Control Act of 1968 (GCA) requires those engaged in importing, manufacturing, or dealing in frearms to obtain federal licenses, keep sales records, conduct background checks, and mark their products with serial numbers. The Act defnes “frearm” to include “(A) any weapon . . . which will or is designed to or may readily be converted to expel a projectile by the action of an explosive; [and] (B) the frame or receiver of any such weapon.” 18 U. S. C. § 921(a)(3). Recent years have wit- nessed profound changes in how guns are made and sold, with companies now able to sell weapon parts kits that individuals can assemble into functional frearms at home. These kits vary widely in how complete they come and in how much work is required to fnish them. Sales have grown exponentially, with law enforcement agencies reporting a Page Proof Pending Publication dramatic increase in untraceable “ghost guns” used in crimes—from 1,600 in 2017 to more than 19,000 in 2021. In 2022, the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) adopted a rule interpreting the Act to cover weapon parts kits that are “designed to or may readily be converted to expel a projectile,” 27 CFR § 478.11, and “partially complete, disassembled, or nonfunc- tional” frames or receivers, § 478.12(c). Before ATF could enforce its rule, gun manufacturers and others fled what they described as a facial challenge under the Administrative Procedure Act, arguing that the GCA cannot be read to reach weapon parts kits or unfnished frames or receivers. The District Court agreed and vacated the rule. The Fifth Circuit affrmed, holding that § 921(a)(3)(A) categorically does not reach weapon parts kits regardless of completeness or ease of assembly, and that § 921(a)(3)(B) reaches only fnished frames and receivers. Held: The ATF's rule is not facially inconsistent with the GCA. Pp. 467– 484. (a) Section 478.11's provisions addressing weapon parts kits are not facially invalid under § 921(a)(3)(A). That subsection contains two re- quirements: a “weapon” must be present, and that weapon must be able to expel a projectile by the action of an explosive, designed to do so, or susceptible of ready conversion to operate that way. Some weapon parts kits meet that description. Consider, for instance, Polymer80's “Buy Build Shoot” kit, which contains all necessary components to build Cite as: 604 U. S. 458 (2025) 459 Syllabus a semiautomatic pistol and can be assembled in about 20 minutes using common tools. That kit qualifes as a “weapon” because: (1) artifact nouns like “weapon” often describe unfnished objects when their in- tended function is clear, as with a disassembled rife; (2) the statute treats starter guns as weapons though they require conversion work; and (3) the statutory text contemplates that some things short of fully operable frearms qualify as “weapons.” The kit also satisfes the stat- ute's second requirement, as it requires no more time, expertise, or spe- cialized tools to complete than a starter gun, which the statute treats as readily convertible into a functioning frearm. While other kits may be so incomplete or cumbersome to assemble that they cannot fairly be described as weapons capable of ready conversion, the facial challenge fails because kits like Polymer 80's clearly qualify. Pp. 467–477. (b) Section 478.12(c)'s treatment of partially complete frames and re- ceivers is also not facially invalid under § 921(a)(3)(B). Like “weapon,” the artifact nouns “frame” and “receiver ” may describe not-yet- complete objects. The statute uses these terms to encompass some un- fnished items elsewhere, as in § 923(i)'s serialization requirements for incomplete weapons, silencers, and destructive devices. ATF has for decades interpreted the statute to reach some unfnished frames and Page Proof Pending Publication receivers, and even the plaintiffs concede they have no “quarrel” with ATF's prior practice of regulating those products. Accordingly, the statute authorizes ATF to regulate at least some incomplete frames or receivers that take minutes of work with common tools to complete. While other products may be so far from fnished that they cannot fairly be described as frames or receivers, the facial challenge fails because the statute plainly reaches some partially complete items. Pp. 477–481. (c) The plaintiffs' arguments about the linguistic differences between subsections (A) and (B) and potential unintended consequences under the National Firearms Act (NFA) are unpersuasive. The government represents that AR–15 receivers do not qualify as machinegun receiv- ers, and this Court's analysis of the GCA does not suggest ATF has authority to regulate them as such under the NFA. Pp. 481–484. (d) Neither the rule of lenity nor constitutional avoidance applies where, as here, the statute's text, context, and structure make clear it reaches some weapon parts kits and unfnished frames or receivers. P. 484. 86 F. 4th 179, reversed and remanded. Gorsuch, J., delivered the opinion of the Court, in which Roberts, C. J., and Sotomayor, Kagan, Kavanaugh, Barrett, and Jackson, JJ., joined. Sotomayor, J., post, p. 485, Kavanaugh, J., post, p. 486, and 460 BONDI v. VANDERSTOK Syllabus Jackson, J., post, p. 487, each fled concurring opinions. Thomas, J., post, p. 488, and Alito, J., post, p. 513, each fled dissenting opinions. Solicitor General Prelogar argued the cause for petition- ers. With her on the briefs were Principal Deputy Assist- ant Attorney General Boynton, Deputy Solicitor General Fletcher, Nicole Frazer Reaves, Mark B. Stern, and Sean R. Janda. Peter A. Patterson argued the cause for respondents. With him on the brief for respondent VanDerStok et al. were David H. Thompson, William V. Bergstrom, Cody J. Wis- niewski, William E. Trachman, R. Brent Cooper, and Mi- chael J. Sullivan. Charles R. Flores, Adam Kraut, and Josh Blackman fled a brief for respondent Defense Distrib- uted et al.* *Briefs of amici curiae urging reversal were fled for the District of Columbia et al. by Brian L. Schwalb, Attorney General of the District of Columbia, Caroline S. Van Zile, Solicitor General, Ashwin P. Phatak, Page Proof Pending Publication Principal Deputy Solicitor General, and Elissa R. Lowenthal, Assistant Attorney General, by Matthew J. Platkin, Attorney General of New Jer- sey, Jeremy Feigenbaum, Solicitor General, and Samuel L. Rubinstein, Deputy Attorney General, by Michelle A. Henry, Attorney General of Pennsylvania, and Lisa E. Eisenberg, Deputy Attorney General, and by the Attorneys General for their respective jurisdictions as follows: Kristin K. Mayes of Arizona, Rob Bonta of California, Philip J. Weiser of Colo- rado, William Tong of Connecticut, Kathleen Jennings of Delaware, Anne E. Lopez of Hawaii, Kwame Raoul of Illinois, Aaron M. Frey of Maine, Anthony G. Brown of Maryland, Andrea J. Campbell of Massachusetts, Dana Nessel of Michigan, Keith Ellison of Minnesota, Aaron D. Ford of Nevada, Letitia James of New York, Joshua H. Stein of North Carolina, Edward E. Manibusan of the Northern Mariana Islands, Ellen F. Rosen- blum of Oregon, Peter F. Neronha of Rhode Island, Charity R. Clark of Vermont, Robert W. Ferguson of Washington, and Joshua L. Kaul of Wisconsin; for the American Medical Association et al. by Michael J. Dell; for the Constitutional Accountability Center by Elizabeth B. Wydra and Brianne J. Gorod; for the District Attorney for New York County et al. by Steven C. Wu, Richard Dearing, and Claude S. Platton; for Global Action on Gun Violence by Timothy C. Hester and Jonathan E. Lowy; for Gun Owners for Safety by Robert M. Radick; for Gun Violence Prevention Groups by Kathleen R. Hartnett, Adam M. Katz, and Patrick J. Hayden; Cite as: 604 U. S. 458 (2025) 461 Opinion of the Court Justice Gorsuch delivered the opinion of the Court. For decades, the Gun Control Act has regulated the sale of frearms. This case poses the question whether the Act's for the Local Government Legal Center et al. by John J. Korzen and Amanda Karras; for the Major Cities Chiefs Association et al. by Mary B. McCord, pro se, Rupa Bhattacharyya, and Kelsi Brown Corkran; for Professors and Scholars of Linguistics and Law by Mark C. Fleming; for Queens County District Attorney's Offce by John M. Castellano; for Frank Blackwell et al. by Lee R. Crain, Scott Edelman, and Katherine M. Marquart; and for 20 Major Cities et al. by Lee S. Richards and Arthur S. Greenspan. Briefs of amici curiae urging affrmance were fled for the State of West Virginia et al. by Patrick Morrisey, Attorney General of West Virginia, and Michael R. Williams, Solicitor General, by Austin Knudsen, Attor- ney General of Montana, Christian B. Corrigan, Solicitor General, and Peter M. Torstensen, Jr., Deputy Solicitor General, and by the Attorneys General for their respective States as follows: Steve Marshall of Alabama, Treg Taylor of Alaska, Tim Griffn of Arkansas, Ashley Moody of Florida, Page Proof Pending Publication Chris Carr of Georgia, Raúl R. Labrador of Idaho, Theodore E. Rokita of Indiana, Brenna Bird of Iowa, Kris Kobach of Kansas, Russell Coleman of Kentucky, Liz Murrill of Louisiana, Lynn Fitch of Mississippi, Andrew Bailey of Missouri, Michael T. Hilgers of Nebraska, John Formella of New Hampshire, Drew Wrigley of North Dakota, Dave Yost of Ohio, Gen- tner Drummond of Oklahoma, Alan Wilson of South Carolina, Marty Jackley of South Dakota, Jonathan Skrmetti of Tennessee, Ken Paxton of Texas, Sean Reyes of Utah, Jason Miyares of Virginia, and Bridget Hill of Wyoming; for the California Gun Rights Foundation by Stephen M. Duvernay; for the Citizens Committee for the Right to Keep and Bear Arms et al. by Dan M. Peterson and C. D. Michel; for the Firearms Regu- latory Accountability Coalition et al. by Stephen J. Obermeier, Jeremy J. Broggi, and Michael D. Faucette; for the Foundation for Moral Law by John A. Eidsmoe; for Gun Owners of America, Inc., et al. by John I. Har- ris III; for the National Association for Gun Rights et al. by David A. Warrington and Gary M. Lawkowski; for the National Association of Sporting Goods Wholesalers by Paul D. Clement, Erin E. Murphy, Mat- thew D. Rowen, and Kevin Wynosky; for the National Rife Association of America by Joseph G. S. Greenlee and Erin M. Erhardt; for the National Shooting Sports Foundation, Inc., by H. Christopher Bartolomucci, Ken- neth A. Klukowski, Stephen P. Halbrook, and Lawrence G. Keane; and for Rick Vasquez et al. by Bradley A. Benbrook. 462 BONDI v. VANDERSTOK Opinion of the Court longstanding mandates also apply to those who make and sell a new product—“weapon parts kits.” I A Shortly after the assassinations of Senator Robert F. Ken- nedy and Dr. Martin Luther King, Jr. stunned the Nation, Congress adopted the Gun Control Act of 1968 (GCA). Pub. L. 90–618, 82 Stat. 1213. Existing gun control measures, Congress found, allowed criminals to acquire largely un- traceable guns too easily. See 82 Stat. 225. Often, for ex- ample, criminals could evade state laws regulating in-person sales simply by purchasing guns through the mail. Ibid. In response, Congress adopted a number of new mandates. As a result, many of those now engaged in importing, manu- facturing, or dealing in frearms must obtain federal licenses, keep records of their sales, and conduct background checks Page Proof Pending Publication before transferring frearms to private buyers. 18 U. S. C. §§ 922(t), 923(a), (g)(1)(A). The Act also requires importers and manufacturers to mark their frearms with serial num- bers. § 923(i). These mandates serve at least two ends. The background-check requirement seeks to keep “guns out of the hands of criminals.” Abramski v. United States, 573 U. S. 169, 180 (2014). The licensing, recordkeeping, and seri- alization requirements, meanwhile, aim “to assist law en- forcement authorities in investigating serious crimes,” ibid., by permitting them “ to determine where, by whom, or when” a firearm was manufactured and to whom it was “sold or otherwise transferred. ” 87 Fed. Reg. 24652 (2022). Today, thousands of law-enforcement agencies nationwide depend on the Act's tracing system to link firearms involved in crimes to their owners. Id., at 24659. The GCA's mandates apply to “frearm[s].” See §§ 922(t), 923(a), (i). And the law defnes that key term broadly. Under § 921(a)(3), a “frearm” includes “(A) any weapon (in- Cite as: 604 U. S. 458 (2025) 463 Opinion of the Court cluding a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of an explosive; (B) the frame or receiver of any such weapon; (C) any frearm muffer or frearm silencer; or (D) any destruc- tive device.” Thanks to this generous defnition, the GCA has long been understood to reach everything from run-of- the-mill rifes to novelty umbrella guns. See AFT, Novelty Guns (June 5, 2015), https://www.atf.gov/firearms/photo- gallery-0. Recent years, however, have witnessed profound changes in how guns are made and sold. When Congress adopted the GCA in 1968, “the milling equipment, materials needed, and designs were far too expensive for individuals to make frearms practically or reliably on their own.” 87 Fed. Reg. 24688. With the introduction of new technologies like 3D printing and reinforced polymers, that is no longer true. Today, companies are able to make and sell weapon parts Page Proof Pending Publication kits that individuals can assemble into functional frearms in their own homes. Ibid. These kits vary widely both in how complete they come and in how much work is required to fnish them. At one end of the spectrum, a kit may lack essential parts and “re- quir[e] substantial effort, specialized expertise, uncommon equipment, and a signifcant amount of time” before anyone can fre a shot. Brief for Former Acting Chief of ATF Fire- arms Technology Branch et al. as Amici Curiae 35. At the other end, some kits “contain all components necessary” for “a complete pistol” and can be completed in perhaps half an hour using commonly available tools. App. to Pet. for Cert. 236a. Sales of these kits have grown “exponential[ly].” Brief for Petitioners 2. Home hobbyists enjoy assembling them. VanDerStock v. Garland, 86 F. 4th 179, 185 (CA5 2023). But criminals also fnd them attractive. Id., at 195. That is largely due to how the kits are sold. Some manufacturers and dealers take the position that weapon parts kits do not 464 BONDI v. VANDERSTOK Opinion of the Court qualify as “frearms” subject to the GCA. As a result, they say, they are free to sell their products without obtaining a federal license, conducting background checks, maintaining sales records, or marking components with serial numbers. 87 Fed. Reg. 24652. The upshot? “[P]olice departments around the Nation” have “confronted an explosion of crimes” involving these “ghost guns. ” Brief for Petitioners 8. In 2017, law- enforcement agencies submitted about 1,600 ghost guns to the federal government for tracing. App. to Pet. for Cert. 194a. By 2021, that number jumped to more than 19,000. Ibid. Efforts to trace the ownership of these weapons, the government represents, have proven “almost entirely futile.” Brief for Petitioners 8. B In 2022, the Bureau of Alcohol, Tobacco, Firearms and Ex- plosives adopted a new rule designed to combat the prolifer- Page Proof Pending Publication ation of ghost guns. See 87 Fed. Reg. 24652. In doing so, the agency invoked authority Congress granted it to pre- scribe “rules and regulations as are necessary to carry out” the GCA. 18 U. S. C. § 926(a). Two provisions in the agency's new rule are of special relevance here. The frst addresses weapon parts kits directly. Recall that § 921(a)(3) extends the GCA's mandates to “frearms,” a term subsection (A) defnes as “any weapon (including a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of an explosive.” In its new rule, ATF interpreted this language to embrace weapon 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.” 27 CFR § 478.11 (2023) (defning “frearm”). Those who make or sell kits that satisfy this test, ATF said, must comply with the GCA by securing federal licenses, conducting background checks, keeping sales records, and marking their products with serial numbers. To decide whether a kit “may readily be converted” into a working gun, ATF added, it will con- Cite as: 604 U. S. 458 (2025) 465 Opinion of the Court sider several factors, including the time, ease, expertise, and equipment required to complete a weapon, as well as the availability of other necessary parts. Ibid. (defining “readily”). The second relevant aspect of the agency's new rule con- cerns a key building block of almost any frearm: its frame or receiver. Under subsection (B) of § 921(a)(3), “the frame or receiver of any such weapon” covered by subsection (A) is itself treated as a “frearm.” Effectively, that means a frame or receiver is, even when sold separately, subject to the Act's requirements. Presumably, Congress singled out these components for special treatment because of the spe- cial role they play in constructing frearms. As the govern- ment put it in 1968, a frame or receiver is “[t]hat part . . . which provides housing for the hammer, bolt or breechblock, and fring mechanism, and which is usually threaded at its forward portion to receive the barrel.” 33 Fed. Reg. 18558; accord, 43 Fed. Reg. 13537 (1978) (formerly codifed at 27 Page Proof Pending Publication CFR § 478.11 (2020)). In its 2022 rule, ATF sought to expand this defnition. Now, the agency said, a “frame or receiver” subject to sub- section (B) of § 921(a)(3), should be understood to encompass as well “a partially complete, disassembled, or nonfunctional frame or receiver, including a frame or receiver parts kit, that is designed to or may readily be completed, assembled, restored, or otherwise converted to function as a frame or receiver.” 27 CFR § 478.12(c) (defning “frame or receiver”). Still, ATF stressed, the Act and its new rule have their lim- its. They do not apply until an object has “reached a stage of manufacture where it is clearly identifable as an unfn- ished component part of a weapon.” Ibid. So, for example, “a forging, casting, printing, extrusion, unmachined body, or similar article” does not count. Ibid.1 1 Besides these changes, ATF's new rule included a number of others. For instance, where the agency's old regulations defned frames and re- ceivers as those parts housing all of a frearm's key components, 43 Fed. Reg. 13537, ATF's new rule redefned those terms to include parts housing 466 BONDI v. VANDERSTOK Opinion of the Court C Before ATF's new rule took effect and ATF could begin efforts to enforce its new rule, various gun manufacturers, at-home gunsmiths, and others fled what they described as a “facial” challenge under the Administrative Procedure Act (APA). See, e. g., BlackHawk Mfg. Complaint in No. 22–619 (ND Tex., Oct. 20, 2022), ECF Doc. 99, p. 25. They argued that the GCA cannot be fairly read to reach weapon parts kits or unfnished frames or receivers. As a result, the plaintiffs contended, ATF's regulations in § 478.11 and § 478.12(c) purporting to extend the GCA's mandates to these products could not be enforced against anyone and had to be “set aside” as impermissibly issued “in excess of statutory . . . authority.” 5 U. S. C. § 706. At summary judgment, the district court agreed with the plaintiffs and vacated the agency's new rule. VanDerStok v. Garland, 680 F. Supp. 3d 741, 766 (ND Tex. 2023). On Page Proof Pending Publication appeal, the Fifth Circuit largely affrmed. The court ac- knowledged that subsection (A) of § 921(a)(3) authorizes ATF to regulate “weapons” that “may readily be converted to expel a projectile by the action of an explosive.” But, the court reasoned, that language does not reach weapon parts kits. Nor does it matter how complete a kit may come or how easily it may be assembled. As a categorical matter, the court held, the Act reaches none of them. 86 F. 4th, at 195. The Fifth Circuit offered a similar assessment when it came to unfnished frames and receivers. Subsection (B) of § 921(a)(3) permits the agency to regulate “the frame or re- ceiver of any such weapon” covered by subsection (A). But, the court held, those terms do not speak to, and thus do not allow the agency to regulate, unfnished frames and receiv- ers, no matter how close to completion they may be. Id., at 190. For these reasons, the court of appeals concluded, the only some key components, see 27 CFR §§ 478.12(a)(1), (a)(2). But because the plaintiffs did not challenge that amendment or others in proceedings be- low, see Brief for Respondent VanDerStok et al. 31, n. 4, we have no occasion to pass upon them, see Cutter v. Wilkinson, 544 U. S. 709, 718, n. 7 (2005). Cite as: 604 U. S. 458 (2025) 467 Opinion of the Court provisions in ATF's new rule addressing weapon parts kits, § 478.11, and unfnished frames and receivers, § 478.12(c), were facially inconsistent with GCA and thus had to be “set aside” consistent with the APA, 86 F. 4th, at 195. The government sought review in this Court. Our inter- vention was necessary, the government insisted, because the court of appeals had “adopted an interpretation of the Act that would effectively nullify its central provisions” and leave criminals today nearly as free to obtain “untraceable frearms” as they were before the Act's adoption in 1968. Pet. for Cert. 28. We agreed to hear the case. 601 U. S. 1161 (2024). II As presented to us, this case does not ask us to resolve whether ATF's new regulations in § 478.11 and § 478.12 may be lawfully applied to particular weapon parts kits or unfn- ished frames or receivers. Instead, the plaintiffs have pur- sued what the lower courts called a “facial” pre-enforcement Page Proof Pending Publication challenge to the agency's authority to regulate any weapon parts kits or unfnished frames or receivers. 680 F. Supp. 3d, at 766; 86 F. 4th, at 186. In a challenge like that, the government represents, “the possibility that [ATF's regula- tion] `may be invalid as applied' in some cases `does not mean that the regulation is facially invalid.' Instead, [the plain- tiffs'] burden is to show that the Rule itself is inconsistent with the statute on its face.” Brief for Petitioners 27–28 (quot- ing INS v. National Center for Immigrants' Rights, Inc., 502 U. S. 183, 188 (1991); citation omitted (addressing a facial chal- lenge under the Immigration and Nationality Act)). No- where in either of their briefs before us do the plaintiffs dis- pute that assessment. Accordingly, we take it as given for our purposes here.2 2 The dissents raise a number of questions about what test courts should apply when a party contends that an agency has acted in excess of its statu- tory authority in a pre-enforcement challenge under the APA. Post, at 494–496 (opinion of Thomas, J.); post, at 515–516 (opinion of Alito, J.). But the theories the dissents proceed to advance were not pressed or passed up- on below, nor did the parties make them before this Court. Cf. post, at 515 468 BONDI v. VANDERSTOK Opinion of the Court In doing so, we turn frst to the question whether § 478.11's provisions addressing weapon parts kits are inconsistent on their face with the GCA. The answer turns on subsection (A) of § 921(a)(3). There, remember, the GCA authorizes ATF to regulate “any weapon (including a starter gun) which will or is designed to or may readily be converted to expel a projectile by the action of an explosive.” Inhering in this language are two requirements. First, a “weapon” must be present. Second, that “weapon” must meet one of three cri- teria: It must be able to expel a projectile by the action of an explosive, designed to do so, or susceptible of ready con- version to operate that way. As the Fifth Circuit saw it, § 478.11's provisions addressing weapon parts kits are fa- cially invalid because no weapon parts kit can ever satisfy the statute's two requirements. We disagree because, to our eyes, at least some kits will satisfy both. A Page Proof To appreciate why, Pending it helps to workPublication with an example. Take a weapon parts kit featured prominently in the record before us: Polymer80's “Buy Build Shoot” kit. It comes with “all of the necessary components to build” a Glock- variant semiautomatic pistol. App. to Pet. for Cert. 219a. And it is so easy to assemble that, in an ATF test, an individ- ual who had never before encountered the kit was able to produce a gun from it in 21 minutes using only “common” tools and instructions found in publicly available YouTube videos. Id., at 220a. The frst picture below shows the kit; the second depicts the gun the kit yields. (opinion of Alito, J.) (suggesting that the Court ask for supplemental briefng). In these circumstances, we believe the better course is to leave further analysis of the proper test for another day and address the parties' dispute as they have chosen to frame it. Nor, on remand, may the parties seek to inject arguments about the proper test that they did not pursue here. See Ohio v. Environmental Protection Agency, 603 U. S. 279, 299 (2024) (forfeiture); Sibbald v. United States, 12 Pet. 488, 492 (1838) (law of the case); contra, post, at 496 (Thomas, J., dissenting). Cite as: 604 U. S. 458 (2025) 469 Opinion of the Court Page Proof Pending Publication Id., at 232a, 238a. 470 BONDI v. VANDERSTOK Opinion of the Court Now, assess whether the “Buy Build Shoot” kit meets sub- section (A)'s two tests, and start with the question whether Polymer80's offering qualifes as a “weapon.” When Con- gress adopted the GCA in 1968, that term meant what it means today: “an instrument of offensive or defensive com- bat [such] as a club, sword, gun, or grenade.” Webster's Third New International Dictionary 2589 (def. 1) (1966); ac- cord, 1 Concise Oxford Dictionary of Current English 1476 (def. 1) (5th ed. 1964). As a result, ATF's authority under subsection (A) extends only to instruments of combat, not to other things like industrial tools or toy guns that may “expel a projectile by the action of an explosive.” It is a feature of the statute the agency itself has long acknowledged. See 87 Fed. Reg. 24684. Plainly, the fnished “Buy Build Shoot” kit is an instrument of combat. No one would confuse the semiautomatic pistol pictured above with a tool or a toy. Of course, as sold, the kit requires some assembly. But a number of considerations Page Proof Pending Publication persuade us that, even as sold, the “Buy Build Shoot” kit qualifes as a “weapon.” Consider, frst, a feature of ordinary language. The term “weapon” is an artifact noun—a word for a thing created by humans. Artifact nouns are typically characterized by an intended function,” rather than by some “ineffable `natural essence.' ” S. Grimm & B. Levin, Artifact Nouns: Reference and Countability, in 2 Proceedings of the Forty-Seventh An- nual Meeting of the North East Linguistic Society (NELS 47) 55 (2017).3 Refecting as much, everyday speakers some- times use artifact nouns to refer to unfnished objects—at least when their intended function is clear. An author might invite your opinion on her latest novel, even if she sends you 3 Accord, Brief for Professors and Scholars of Linguistics and Law as Amici Curiae 6–9; J. Pustejovsky, The Generative Lexicon 97 (1995); J. Coleman & O. Simchen, “Law,” 9 Legal Theory 1, 20 (2003); T. Parsons, The Progressive in English, 12 Linguistics in Philosophy 213, 225–226 (1989). Cite as: 604 U. S. 458 (2025) 471 Opinion of the Court an unfnished manuscript. A friend might speak of the table he just bought at IKEA, even though hours of assembly re- main ahead of him. In both cases, the artifact noun fts be- cause the intended function of the unfnished object is obvi- ous to speaker and listener alike. The term weapon can work this way, too. Imagine a rife disassembled for storage, transport, or cleaning. It may take time to render the rife useful for combat, but its in- tended function is clear. And, as a matter of every day speech, that rife is a weapon, whether disassembled or com- bat ready. In the same way and for the same reason, an ordinary speaker might well describe the “Buy Build Shoot” kit as a “weapon.” Yes, perhaps a half hour of work is re- quired before anyone can fre a shot. But even as sold, the kit comes with all necessary components, and its intended function as instrument of combat is obvious. Really, the kit's name says it all: “Buy Build Shoot.” Page Proof Pending Publication Next, consider what the statute itself has to say about the term “weapon.” Subsection (A) tells us that the term “in- clud[es] a starter gun.” § 921(a)(3)(A). A starter gun, of course, normally fres blanks, not bullets, and is usually found at sporting events, not in combat. See United States v. Hall, 396 F. 2d 841, 842, n. 2 (CA4 1968). To be sure, a starter gun can be converted to live fre using a power tool commonly available at hardware stores. See United States v. Mullins, 446 F. 3d 750, 755 (CA8 2006). For someone with no “specialized knowledge,” the process can take “less than an hour.” Ibid. But, notably, the statute teaches that a starter gun is a “weapon” before anyone invests that work. All of which indicates that Congress used that term, as an ordinary speaker might, to embrace some unfnished instru- ments of combat like Polymer80's product. Finally, notice another feature of the statute. If Congress had wanted to regulate only operable frearms, it could have simply addressed “weapons” that can “expel a projectile by the action of an explosive.” But Congress didn't stop there. 472 BONDI v. VANDERSTOK Opinion of the Court Instead, Congress explained that a “weapon” also qualifes for regulation if it is either “designed” to accomplish that function or capable of being “readily . . . converted” to do so. § 921(a)(3)(A). Those latter provisions necessarily contem- plate that some things short of fully operable frearms will qualify as “weapons.” And if that is true, it is diffcult to see how the easy-to-assemble “Buy Build Shoot” kit might not be among them. Of course, to implicate the Act, not only must a “weapon” be present. That weapon must meet one of the just- recounted conditions. At a minimum, that means a weapon must be capable of being “readily . . . converted to expel a projectile by the action of an explosive.” Ibid. As we see it, the “Buy Build Shoot” kit satisfes that test, too. Begin with what we can glean about the “ready-conversion” standard from the statute. We know that Congress's direc- tion that a starter gun is a “weapon” would be pointless un- Page Proof Pending Publication less a starter gun satisfes all subsection (A)'s terms. For the statute to make sense, then, a starter gun must be able to fre bullets, designed to do so, or capable of ready conver- sion to operate that way. Generally, however, a starter gun meets neither of the frst two conditions, for its barrel is deliberately blocked. See United States v. 16,179 Molso Italian .22 Caliber Winlee Derringer Convertible Starter Guns, 443 F. 2d 463, 465 (CA2 1971). That leaves only one serious possibility: It must be that a starter gun “can readily be converted to expel projectiles by the action of an explosive.” That turns out to tell us all we need to know about the statute's “ready conversion” test. As we have seen, a per- son without any specialized knowledge can convert a starter gun into a working frearm using everyday tools in less than an hour. Mullins, 446 F. 3d, at 755. And measured against that yardstick, the “Buy Build Shoot” kit can be “readily con- verted” into a frearm too, for it requires no more time, ef- fort, expertise, or specialized tools to complete. App. to Pet. Cite as: 604 U. S. 458 (2025) 473 Opinion of the Court for Cert. 220a. If the one meets the statutory test, so must the other. Admittedly, our reasoning here has its limits. Just be- cause some kits, like Polymer80's, qualify as “weapons” that “can readily be converted” into working frearms does not mean all do. Think of the problem of the heap: Start with a heap of sand and begin removing grains; at some point, a heap no longer exists. That problem attends many artifact nouns. Even when used to capture unfnished products, ar- tifact nouns generally reach only so far. It would be extrav- agant to speak of a novel when the author has dashed off only a few lines. Few would call a pile of unfnished logs a table. Subsection (A) may present a similar problem. Weapon parts kits vary widely. See Part I–A, supra. Not all come as complete as the “Buy Build Shoot” kit. Some, too, may require more time, expertise, or specialized tools to fnish. And at some point a kit may be so incomplete or cumbersome to assemble that it can no longer fairly be de- Page Proof Pending Publication scribed as a “weapon” capable of “read[y] . . . conver[sion]” into a working frearm. § 921(a)(3)(A). While we recognize the problem, this case does not require us to untangle exactly how far subsection (A) reaches. The plaintiffs argue only that § 478.11's provision addressing weapon parts kits is facially inconsistent with the statute. The Fifth Circuit adopted the same view after coming to the unqualifed conclusion that weapon parts kits can never sat- isfy the statute's two tests. To resolve this case, it is enough to say those assessments are mistaken. Because at least some weapon parts kits satisfy both of subsection (A)'s tests, § 478.11 is not facially invalid. Future cases may present other and more diffcult questions about ATF's regulations. But we take cases as they come and today resolve only the question posed to us. B The plaintiffs dispute little of what we have said. They admit that artifact nouns sometimes capture unfnished arti- 474 BONDI v. VANDERSTOK Opinion of the Court cles. Tr. of Oral Arg. 76–77. They recognize that starter guns qualify as “weapons” even though they require work before they operate as functional firearms. Brief for Respondent VanDerStok et al. 34. The plaintiffs concede, too, that disassembled rifes and guns are “weapons” that can be “readily . . . converted” to live fre because they have “all the parts necessary” for an ordinary person “to put toget- her a functioning frearm” in short order. Id., at 37. Really, the plaintiffs fail only to take the next step and ac- knowledge that the same might be said of some weapon parts kits. Given all that, what do the plaintiffs have to say in support of the Fifth Circuit's conclusion that subsection (A) reaches no weapon parts kits? Perhaps their best argument centers on the fact that other statutes address collections of parts while this one does not. As the plaintiffs observe, Congress has elsewhere defned a “destructive device” to embrace Page Proof Pending Publication “any combination of parts . . . from which a destructive de- vice may be readily assembled.” § 921(4)(C). Similarly, Congress has specifed that the terms “frearm silencer” and “frearm muffer” encompass “any part” or “combination of parts” used to “assembl[e] or fabricat[e]” those items. § 921(a)(25); see also Federal Firearms Act of 1938, 52 Stat. 1250 (defning “frearm” to include “any part or parts of such weapon”). Subsection (A), meanwhile, employs none of those terms. And because Congress has spoken elsewhere to collections of frearm parts, the plaintiffs insist, we should infer this statute does not address parts or kits containing any combinations of them. The plaintiffs' conclusion, however, does not follow from their premise. We do not doubt that subsection (A) sweeps more narrowly than some other statutes. No one thinks it reaches every piece or part that can be used to produce a frearm. Recognizing as much, ATF itself acknowledges that subsection (A) does not allow it to regulate “standalone triggers, barrels, stocks, or magazines.” Brief for Petition- Cite as: 604 U. S. 458 (2025) 475 Opinion of the Court ers 24. Nor, the agency admits, does the statute authorize it to regulate “weapon parts writ large,” without regard to how complete they come or how diffcult they are to as- semble. Ibid. But the fact that subsection (A) doesn't go as far as some other statutes does not tell us how far it does go. Let alone prove that subsection (A) fails, as a categori- cal matter, to reach any weapon parts kits. Faced with that problem, the plaintiffs, joined now by the dissent, try another tack. They object that weapon parts kits cannot be “weapons” under subsection (A) because they lack functional frames or receivers. See Brief for Respond- ent VanDerStok et al. 35; post, at 507–508 (opinion of Thomas, J.) (advancing a similar argument). That conclu- sion rests on two premises: (1) that a “weapon” must have a fully “functional” frame or receiver, and (2) that no “weapon- parts kit” includes such a part. Post, at 507–508 (opinion of Thomas, J.). But neither premise is sound. For one, the Page Proof Pending Publication statute nowhere says that a “weapon” must have a fully func- tional frame or receiver—nor is it obvious how we might derive such a rule from its terms. In fact, as we have seen, subsection (A) reaches any “weapon” that may “readily be converted” to live fre. § 921(a)(3)(A). And a gun that is fully operable, save for a frame missing a single and easily- added screw, would surely ft that description. See Part II– A, supra. For another, even if the statute did require a “weapon” to have a fully functional frame or receiver, some weapon parts kits may ft that description. Imagine a kit identical to Polymer80's in all respects, except that it has a complete frame. Even the plaintiffs would have to ad- mit that such a kit would count as a “weapon” under sub- section (A). Failing all else, the dissent suggests that other criminal statutes addressing “frearm[s]” prove that weapon parts kits cannot fall within the statutory defnition of that term. Post, at 508–509. So, for example, the dissent observes that Con- gress has penalized the use of “frearm[s]” during and in rela- 476 BONDI v. VANDERSTOK Opinion of the Court tion to a “crime of violence,” § 924(c), required “frearm[s]” to be “unloaded” during transportation, § 926A, and permit- ted law-enforcement offcers to carry “concealed frearm[s],” § 926B. And, the dissent continues, it is “hard to imagine” how any of those provisions might apply to weapon parts kits. Post, at 509. As a result, the dissent insists, we should prefer a reading that limits the term “frearm” to completely operable guns. Ibid. This argument suffers at least two problems as well. First, what the dissent fnds hard to imagine turns out to be anything but, for various criminal laws addressing frearms can apply to weapon parts kits. Just consider some of the laws we have already encountered that require those who import, manufacturer, or deal in “frearms” to obtain federal licenses, keep records of their sales, and conduct background checks. §§ 922(t), 923(a), (g)(1)(A). Plainly, those criminal laws can be applied sensibly to weapon parts kits. Or, to Page Proof Pending Publication take one of the dissent's own examples, a weapon parts kit might be “possesse[d]” “in furtherance of ” a “crime of vio- lence” in violation of § 924(c)(1) when an individual accused of attempted robbery purchases the kit for assembly and use in an upcoming heist. See Stokeling v. United States, 586 U. S. 73 (2019) (holding that a state robbery statute qualifes as a crime of violence). Second, the dissent's complaint is hardly resolved by adopting its view of the statute. The dissent must acknowl- edge, for example, that standalone “frame[s] or receiver[s]” and “silencer[s]” qualify as “frearms,” for the statute tells us so expressly. § 921(a)(3). Yet, only rarely would some- one use a standalone “frame or receiver” during a “crime of violence,” § 924(c), and it may be impossible to “unloa[d]” a “silencer” during “transportation,” § 926A. So whether one adopts our interpretation or the dissent's, not every “fre- arm” will be capable of implicating every criminal law dis- cussing frearms. It's a fact that, if it proves anything, Cite as: 604 U. S. 458 (2025) 477 Opinion of the Court proves only that Congress's defnition of “frearm” is a capa- cious one indeed.4 III That leaves the question whether ATF's new regulation addressing unfnished frames and receivers, § 478.12(c), is fa- cially inconsistent with the GCA. The answer here turns on subsection (B) of § 921(a)(3). That provision of the statute permits the agency to regulate the “frame or receiver of any such weapon.” As the Fifth Circuit saw it, this language reaches only fnished frames or receivers. So those who make, import, or sell partially complete frames or receivers may do so free from the GCA's mandates, no matter how quickly and easily their products can be fnished, and ATF is powerless to hold otherwise. Once again, the plaintiffs ask us to endorse that categorical conclusion. And, once again, we fnd we cannot. The GCA reaches, and permits ATF to regulate, at least some “partially complete” frames or receiv- Page Proof Pending Publication ers. § 478.12(c). 4 Separately, the dissent seems to dismiss the possibility that Congress might use an artifact noun in a way that encompasses incomplete objects. Post, at 502–503 (opinion of Thomas, J.). But the dissent does not dispute that our task here, as ever, is to interpret the words Congress enacted “consistent with their ordinary meaning.” Wisconsin Central Ltd. v. United States, 585 U. S. 274, 278 (2018). Nor does the dissent dispute that ordinary speakers sometimes use artifact nouns to reach incomplete objects. In fact, the dissent ultimately concedes that even Congress “might sometimes” do the same. Post, at 503–504, n. 7 (opinion of Thomas, J.). At bottom, then, the dissent's only point appears to be that “traditional methods of statutory interpretation” should guide us in as- sessing whether Congress meant for a particular artifact noun to reach incomplete objects. Ibid. On that, we agree. And here, as we have seen, one of the most traditional tools for discerning statutory meaning— contextual clues found in the pertinent statute itself—suggest that Con- gress used the term “weapon” to reach at least some unfnished instruments of combat. In saying as much, we do not suggest that Congress always uses artifact nouns to reach incomplete objects—only that we are per- suaded it did so here. 478 BONDI v. VANDERSTOK Opinion of the Court A Working with another example drawn from the record helps illustrate why this is so. The frst photograph below depicts the complete frame of a Glock-variant frearm, the second a partially complete frame that Polymer80 sells. Page Proof Pending Publication App. 259, 263. The main differences between the completed frame and Polymer80's product are the plastic tabs circled in red. Brief for Petitioners 34–35. The record suggests that those tabs “are easily removable by a person with novice skill, Cite as: 604 U. S. 458 (2025) 479 Opinion of the Court using common tools . . . , within minutes.” App. 262. Once the tabs are gone and a “few holes are drilled for the pins that hold [other] parts in place—again, a task that anyone can complete in minutes—the Polymer80 product is a fully functional frame.” Brief for Petitioners 35. A number of reasons persuade us that this qualifes as a “frame” for purposes of subsection (B). First, like the word “weapon” in subsection (A), the terms “frame” and “re- ceiver” in subsection (B) are artifact nouns. And, as artifact nouns, they may sometimes describe not-yet-complete ob- jects. Recall the author who refers to her manuscript as a novel, or your friend who calls his IKEA kit a table. In much the same way, an ordinary speaker might well call Polymer80's product a frearm “frame,” even though a little work is required to complete it. Just look again at the sec- ond photo. What else would you call it? Next, consider how the GCA uses the words “frame” and Page Proof Pending Publication “receiver” elsewhere. Section 923(i) spells out the Act's se- rialization mandate. It requires those who make or sell “frearms” to identify their products “by means of a serial number engraved or cast on the receiver or frame.” Though this directive may seem simple enough, it is complicated by the fact that the statutory defnition of “frearm” in- cludes some incomplete “weapon[s],” “muffer[s],” “silenc- er[s],” and “destructive device[s].” § 921(a)(3). Sometimes, those items lack a fnished or prototypical frearm frame or receiver. Yet, all the same, § 923(i) treats them as “fre- arms” that must have a serial number engraved or cast on their “frame[s]” or “receiver[s].” And if the words “frame” and “receiver” encompass some unfnished and unconven- tional frames or receivers in § 923(i), it is hard to see how those same words might bear a more restrictive meaning when they appear just a few sections away in § 921(a)(3)(B). See Azar v. Allina Health Services, 587 U. S. 566, 574 (2019) (recounting the usual rule that a word carries the same meaning throughout a single statute); post, at 505 (Thomas, 480 BONDI v. VANDERSTOK Opinion of the Court J., dissenting) (admitting that a contrary interpretation re- quires giving the terms “frame” and “receiver” different meanings in different places). Here, too, examples help. Imagine a handgun that is oth- erwise ready to shoot, but contains Polymer80's incomplete frame. An ordinary person, using ordinary tools, can fnish the frame in minutes. App. 262. For reasons explored in Part II, supra, that gun is a weapon capable of ready conver- sion into a working frearm under subsection (A). So § 923(i) requires the gun's “frame”—the very item that isn't fully fnished—to bear a serial number. Along similar lines, consider silencers. They lack traditional frames, but § 923(i) requires manufacturers and importers to serialize them. To accommodate that instruction, ATF has long deemed the “outer tube . . . that provides housing or a structure for the primary internal component” to be a silencer's “frame or re- ceiver.” 27 CFR § 478.12(b); accord, § 478.92(a)(4)(ii) (sup- Page Proof Pending Publication plying directions for “destructive devices”). In all these ways and more, § 923(i) uses the phrase “frame or receiver” to reach some unfnished and unconventional frames and re- ceivers, making it only sensible to think the same phrase does the same work a few doors away in § 921(a)(3)(B). The novelty of the plaintiffs' complete-items-only reading of subsection (B) supplies another strike against it. Without question, ATF's new rule seeks to regulate a greater variety of unfnished frames and receivers than the agency has in the past. But it is equally true that, for decades, the agency has consistently interpreted subsection (B) to reach some unfn- ished frames and receivers, including ones no more fnished than Polymer80's product. See, e. g., ATF, Are “80%” or “Unfnished” Receivers Illegal? (Apr. 6, 2020), https://www. atf.gov/frearms/qa/are-“80”-or-“unfnished”-receivers-illegal; App. 117–118 (2013 guidance); id., at 5, 8, 10 (1990–1994 clas- sifcation letters); id., at 22 (deeming a frame with additional “material left on top” to be a “frearm”). And while “courts must exercise independent judgment in determining the Cite as: 604 U. S. 458 (2025) 481 Opinion of the Court meaning of statutory provisions,” the contemporary and con- sistent views of a coordinate branch of government can pro- vide evidence of the law's meaning. Loper Bright Enter- prises v. Raimondo, 603 U. S. 369, 394 (2024).5 Last but not least, the plaintiffs represent that they have no “quarrel” with ATF's “prior practice.” Tr. of Oral Arg. 59. It is a concession that all but gives the game away. Of course, the plaintiffs think the agency's new rule reaches fur- ther than the statute can bear by seeking to regulate some products too far removed from fnished frames or receivers. But, for our purposes, what matters is that even the plain- tiffs do not really insist that subsection (B) reaches only fn- ished frames and receivers. Here, again, our reasoning has its limits. In saying that a product like Polymer80's qualifes as a “frame,” we do not suggest that the GCA reaches, and ATF may regulate, any combination of parts susceptible of conversion into a frame or receiver with suffcient time, tools, and expertise. Like Page Proof Pending Publication the term “weapon,” the artifact nouns “frame” and “re- ceiver” have their bounds. Some products may be so far from a fnished frame or receiver that they cannot fairly be de- scribed using those terms. But this case requires us to ex- plore none of that. The plaintiffs do not challenge ATF's new rule as applied to particular products. They argue only that § 478.12 is facially inconsistent with the GCA. And, here again, we have no trouble rejecting that unqualifed view. B Resisting our conclusion on this score, the plaintiffs and dissent press three main replies. 5 The dissent admits that ATF's prior practice was to “evaluat[e] the level of completion” when deciding whether an unfnished object was a “regulable frame or receiver.” Post, at 492 (opinion of Thomas, J.) (quoting App. 23). So even if the new rule looks at different evidence in making that same determination, post, at 499–500, it refects the agency's consist- ent understanding that subsection (B) reaches some incomplete “frames or receivers.” 482 BONDI v. VANDERSTOK Opinion of the Court First, they point to a linguistic difference between subsec- tions (A) and (B). In subsection (A), Congress chose to reg- ulate “weapons” that “can readily be converted” into operat- ing frearms. Meanwhile, in subsection (B) Congress spoke only of “frames or receivers,” not parts that “can readily be converted” into those things. And, as the plaintiffs see it, that omission counsels against reading subsection (B) to reach any unfnished frames or receivers. Brief for Re- spondent VanDerStok et al. 19; see also post, at 498–499 (Thomas, J., dissenting) (making a similar point). This argument fails to persuade us for a number of familiar reasons. For one, it does not account for the fact that ordi- nary speakers sometimes use unadorned artifact nouns like “weapon,” “frame,” or “receiver” to reach unfnished articles. Adopting the plaintiffs' argument would also require us to read the phrase “frame or receiver” in § 921(a)(3)(B) to embrace only fnished products, even though § 923(i)'s use Page Proof Pending Publication of the same phrase sweeps more broadly. To accept this argument, we would have to disregard as well the plain- tiffs' concession that the terms “frame” and “receiver” in subsection (B) are properly understood, as they have been long understood, to reach some unfinished frames or receivers. Even beyond all that, reading subsection (B) in light of subsection (A) does more to undermine than to advance the plaintiffs' cause. Subsection (B) speaks of the “frame or re- ceiver of any such weapon. ” § 921(a)(3)(B) (emphasis added). That italicized phrase refers us back to weapons encompassed by subsection (A). And, as we have seen, the term “weapon” in subsection (A) encompasses some things that are not yet ft for effective use in combat, including starter guns and disassembled rifes, as well as certain weapon parts kits. Subsection (B) expressly incorporates that defnition of “weapon.” And, if anything, the fact that Congress used one artifact noun (“weapon”) in subsection (B) to reach some unfnished articles suggests it used two other Cite as: 604 U. S. 458 (2025) 483 Opinion of the Court artifact nouns (“frame” and “receiver”) in the same way in the same provision. Second, the plaintiffs and the dissent contend, our inter- pretation of subsection (B) could invite a serious unintended consequence under a separate statute, the National Fire- arms Act (NFA), ch. 757, 48 Stat. 1236. That law bans the possession of “machinegun[s],” a term Congress has defned to include the “frame or receiver” of “any such weapon.” 26 U. S. C. § 5845(b). Interpreting the GCA to reach some unfnished frames or receivers, the plaintiffs reason, might lead the government to attempt a similar read- ing of the NFA. And if the government takes that step, the plaintiffs suggest, it might next attempt to classify the receiver of an AR–15 rife as a “machinegun” because it “is possible to convert” those receivers “to function as machinegun receivers.” Brief for Respondent VanDerStok et al. 15; see also post, at 500 (Thomas, J., dissenting). That Page Proof Pending Publication result, the plaintiffs warn, could leave many Americans facing new and unforeseen criminal liability for possession of a “machinegun” simply because they own a “popular” and “commonly available” rifle. Brief for Respon- dent VanDerStok et al. 22 (quoting Garland v. Cargill, 602 U. S. 406, 430 (2024) (Sotomayor, J., dissenting)); 87 Fed. Reg. 24652. The plaintiffs' fears are misplaced. The government rep- resents that AR–15 receivers do not “qualify as the re- ceiver of a machinegun.” Reply Brief 11–12. Nor, the gov- ernment emphasizes, has ATF ever “suggested otherwise.” Ibid. Much the same can be said of our reasoning today. As we have stressed, a statute's text and context are criti- cal to determining whether (and to what extent) Con- gress used an artifact noun to reach unfnished objects. And, without doubt, the NFA and the GCA are different statutes passed at different times to address different prob- lems using different language. Our analysis of the GCA thus does not begin to suggest that ATF possesses authority 484 BONDI v. VANDERSTOK Opinion of the Court to regulate AR–15 receivers as machineguns under the NFA. Third, the plaintiffs criticize ATF's rule for permitting the agency to consider “jigs,” “tools,” and “instructions” when deciding whether an incomplete “frame or receiver” is close enough to the fnished product to fall under subsection (B). Brief for Respondent VanDerStok et al. 25–26. The dissent echoes the complaint, offering a photo from the record de- picting various tools and jigs. See post, at 501 (opinion of Thomas, J.). But if this is a problem at all, it is one for another day. As litigated, this case does not call on us to address what weight, if any, ATF may lawfully give jigs, tools, and instructions when deciding whether a frame or re- ceiver is present. This case requires us to answer only whether subsection (B) reaches some incomplete frames or receivers. Saying that it does is enough to resolve the dis- pute before us. * Page Proof Pending Publication The plaintiffs close by asking us to invoke the rule of lenity or the doctrine of constitutional avoidance to resolve in their favor any ambiguities about § 921(a)(3). Brief for Respond- ent VanDerStok et al. 38; see also post, at 511–512 (Thomas, J., dissenting). But neither lenity nor avoidance has any role to play where “text, context, and structure” decide the case. Van Buren v. United States, 593 U. S. 374, 393–394 (2021). And even if ambiguities at the outer boundaries of subsec- tions (A) and (B) emerge in future disputes involving the application of those provisions to particular products, no room for doubt exists about the answer to the question the parties have posed to us. The GCA embraces, and thus per- mits ATF to regulate, some weapon parts kits and unfnished frames or receivers, including those we have discussed. Be- cause the court of appeals held otherwise, its judgment is reversed, and the case is remanded for further proceedings consistent with this opinion. It is so ordered. Cite as: 604 U. S. 458 (2025) 485 Sotomayor, J., concurring Justice Sotomayor, concurring. I join the Court's opinion in full. I write separately to address two points raised in the writings that follow. The frst is a concern that ATF's rule might leave regulated enti- ties in doubt about when and how to comply with the Gun Control Act. See post, at 486 (Kavanaugh, J., concurring). That worry is unfounded. For more than half a century, frearms dealers, manufac- turers, and importers have complied with the Gun Control Act's requirements. They have marked their products with serial numbers, kept records of frearm sales, and conducted background checks for prospective buyers. See 18 U. S. C. §§ 922(t), 923(g)(1)(A), 923(i). These requirements are not new to the industry, and covered entities know they must maintain familiarity with the statute and accompanying reg- ulations to run their businesses. In fact, the Act requires such entities to obtain federal licenses before selling, manu- Page Proof Pending Publication facturing, or importing any firearms in the first place. § 923(a). What is new is that some manufacturers have sought to circumvent the Act's requirements by selling easy-to- assemble frearm kits and frames, which they claim fall outside the statute's scope. See 87 Fed. Reg. 24652, 24655, 24686 (2022). ATF's rule simply confrms what was already clear: The Gun Control Act does not tolerate such evasion. Its plain text covers frearm kits and unfnished frames or receivers designed for ready conversion, as the Court explains. So, for entities who seek to comply with the Act in good faith, ATF's rule should come as no surprise. Nor should it create any diffculty discerning how to abide by the law. To the extent any manufacturer has doubts about whether a particular product qualifes as a covered frearm, moreover, it can eliminate uncertainty by seeking clarifcation from the agency. ATF encourages manufacturers to submit poten- tially covered products to the agency for classifcation deci- sions. See Brief for Petitioners 5 (citing Dept. of Jus- 486 BONDI v. VANDERSTOK Kavanaugh, J., concurring tice, ATF, Offce of Enforcement Programs & Servs., ATF National Firearms Act Handbook 41 (ATF E-Publication 5320.8 rev. Apr. 2009)); 27 CFR § 478.92(c) (2023). Manufac- turers have long taken advantage of that process, see, e. g., App. 8, 10–12, 21–22, 50–52, 53–54, and a failure to do so might suggest willfulness on their part. The second point I address is the suggestion that the Act permits ATF to regulate only “all-but-assembled” weapon parts kits and frames “as close to completion as possible.” Post, at 513 (Alito, J., dissenting). The Court's opinion speaks for itself on that point and others. I encourage read- ers to go to the source, rather than rely on dissents, to under- stand what the Court holds. See ante, at 467, 471–472, 478, 480–482, 484. It is the Court's ruling, not the one set forth by the dissents, that binds the lower courts. Justice Kavanaugh, concurring. Page Proof Pending Publication I join the Court's opinion in full. I add this concurrence to briefy address mens rea issues with respect to ATF's 2022 rule. Under ATF's rule, an individual or business acting in good faith might nonetheless have substantial diffculty determin- ing when weapon parts kits or unfnished frames or receivers qualify as frea