The Clean Air Act (CAA) establishes a tripartite system for determining venue in CAA litigation. Challenges to “nationally applicable” Environmental Protection Agency (EPA) actions belong in the U. S. Court of Appeals for the D. C. Circuit, while challenges to “locally or regionally applicable” EPA actions ordinarily belong in a regional Circuit. 42 U. S. C. § 7607(b)(1). But, the CAA makes an exception for local or regional actions that are “based on a determination of nationwide scope or effect” and accompanied by an EPA fnding of this basis, which also must be challenged in the D. C. Circuit. Ibid. Applying this framework to EPA's 2022 denials of certain small refneries' exemption petitions, we hold that the refneries' challenges belong in the D. C. Circuit. EPA's denials are only locally or regionally applicable, but they fall within the “nationwide scope or effect” exception.
I
A
Section 7607(b)(1)—the CAA's venue provision—governs where petitioners should fle challenges to EPA actions under that statute. As originally enacted, § 7607(b)(1) dictated venue only for an enumerated subset of EPA actions.
Certain actions with a national reach, such as “any national primary or secondary ambient air quality standard” (NAAQS) were reviewable only in the D. C. Circuit.
§ 1857h–5(b)(1) (1970 ed.). Area-specific “implementation plan[s]” went to “the appropriate” regional Circuit. Ibid. Any other unmentioned actions could be heard only in district courts through their general grant of federal-question jurisdiction. Harrison v. PPG Industries, Inc., 446 U. S. 578, 584 (1980); see 28 U. S. C. § 1331.
In 1977, Congress replaced this patchwork system with the CAA's current scheme, which makes all EPA actions directly reviewable in a federal court of appeals. 91 Stat. 776 Page Proof Pending Publication Page Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
(codified as amended at 42 U. S. C. § 7607(b)(1)).
The amended statute specifes that, in addition to NAAQS and other enumerated actions, “any other nationally applicable . . . fnal action taken” by EPA under the CAA may be reviewed only in the D. C. Circuit. § 7607(b)(1). And, in addition to implementation plans, “any other fnal action of [EPA] under this chapter . . . which is locally or regionally applicable” ordinarily may be reviewed only in a regional Circuit. Ibid. Congress has since amended the CAA to specify additional kinds of actions that fall within these two categories. 91 Stat. 1404; 104 Stat. 2681.
Congress also created a third venue category in the 1977 amendments. This category provided an exception to the default rule that locally or regionally applicable actions should be reviewed in the regional Circuits. Congress instructed that a locally or regionally applicable action must be reviewed in the D. C. Circuit “if [it] is based on a determination of nationwide scope or effect” and “if in taking such action [EPA] fnds and publishes that such action is based on such a determination.” § 7607(b)(1).
B
The EPA actions at issue in this case relate to the CAA's renewable fuel program (RFP). The RFP “requires most domestic refneries to blend a certain amount of ethanol and other renewable fuels into the transportation fuels they produce.” HollyFrontier Cheyenne Refning, LLC v. Re newable Fuels Assn., 594 U. S. 382, 385 (2021). Each covered refnery's precise obligation turns on its proportional share of various “nationwide volume mandates.” Id., at 385–386; see §§ 7545(o)(2)(A)(i), (o)(3); 40 CFR § 80.1407(a) (2024).
Covered refneries demonstrate compliance through a system of Renewable Identifcation Number credits (RINs).
See 40 CFR §§ 80.1425, 80.1426(a). A refnery generates RINs whenever it blends renewable fuels, § 80.1426(a), and refneries may also buy and sell RINs, 42 U. S. C. § 7545(o)(5)(B). Thus, each year, a refnery may show compliance “thanks to its own blending efforts, the purchase of credits from someone else, or a combination of both.”
HollyFrontier, 594 U. S., at 386.
The CAA contains a phased exemption scheme for small refneries—i. e., refneries whose “average aggregate daily crude oil throughput for a calendar year . . . does not exceed 75,000 barrels.” § 7545(o)(1)(K). The scheme exempted all small refneries from RFP compliance until 2011. § 7545(o) (9)(A)(i). It then required EPA to extend this blanket exemption, for at least two years, for all small refneries found by a Department of Energy study to face “disproportionate economic hardship” if subjected to the RFP's obligations.
§ 7545(o)(9)(A)(ii). Finally, the scheme allows a small refnery to “at any time petition [EPA] for an extension of [its] exemption . . . for the reason of disproportionate economic hardship.” § 7545(o)(9)(B)(i). We interpreted this last provision in HollyFrontier, holding that a small refnery may obtain an “extension” even after its original exemption has lapsed. Id., at 396.
C
This case arose in the aftermath of HollyFrontier. Pending that decision, the D. C. Circuit had been holding in abeyance challenges to EPA's resolution of 36 small refneries' exemption petitions for the 2018 compliance year. Afterwards, that court granted EPA's motion for remand without vacatur, so that EPA could reconsider its orders in light of the HollyFrontier litigation. Order in Sinclair Wyoming Refning Co. v. EPA, No. 19–1196 etc. (CADC, Dec. 8, 2021), p. 3. The D. C. Circuit instructed EPA to issue its new decisions within 120 days. Ibid. Shortly thereafter, EPA noticed for public comment a proposal to deny all pending exemption petitions. 86 Fed. Reg. 71000 (2021). EPA's notice set out two principles. First, EPA offered its interpretation of “disproportionate economic Page Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
hardship,” the CAA's threshold for an exemption petition to be granted. § 7545(o)(9)(B)(i). On EPA's view, that phrase covers only hardship that is caused by RFP compliance.
App. in No. 22–60266 etc. (CA5), pp. 545–548. Second, EPA theorized that, as a matter of economics, small refneries ordinarily do not suffer disproportionate economic hardship as a result of the RFP because “RIN costs are fully passed through to consumers.” Id., at 549; see id., at 548–584.
Based on this “RIN passthrough” theory, EPA proposed denying all pending petitions “by fnding the petitioning refneries do not face [disproportionate economic hardship] caused by compliance with their [RFP] obligations.” 86 Fed. Reg.
71000.
After receiving comments, EPA followed through and denied the pending exemption petitions in two omnibus notices. EPA issued the frst in April 2022 to deny the 36 petitions subject to the D. C. Circuit's deadline. 87 Fed. Reg. 24300. EPA issued the second in July 2022, to deny an additional 69 petitions from the 2016 to 2021 compliance years. Id., at 34874. In both notices, EPA relied primarily on the principles from its proposal—namely, its statutory interpretation of “disproportionate economic hardship” and its RIN pass- through theory. App. to Pet. for Cert. 100a, 107a, 242a, 249a. EPA treated the passthrough theory as creating a presumption against granting exemptions, and it examined the petitioning refneries' evidence regarding their specifc circumstances to confrm that none of the refneries had rebutted this presumption. See id., at 107a–108a, 163a–168a, 249a–250a, 305a–310a.
EPA also asserted in the denial notices that its denials were reviewable only in the D. C. Circuit. According to EPA, the notices were “ `nationally applicable' ” actions under § 7607(b)(1). Id., at 187a, 328a. Alternatively, if the actions were only “locally or regionally applicable,” then EPA invoked the exception for actions “based on a determination of `nationwide scope or effect.' ” Ibid. EPA inPage Proof Pending Publication cluded in both notices a fnding that its new statutory interpretation and RIN passthrough theory supplied the relevant determinations of nationwide scope or effect. Id., at 187a–188a, 329a.
Notwithstanding EPA's position, small refneries challenged these denials in a host of regional Circuits. Agreeing with EPA that the litigation belonged in the D. C. Circuit, most of these Circuits either dismissed the petitions for improper venue or transferred them to the D. C. Circuit.1 The Fifth Circuit took a different approach. Evaluating the petitions fled by six small refneries (respondents here), the Fifth Circuit held that the litigation was properly before it. The majority rejected the arguments for transfer raised by EPA and a group of intervenors, reasoning that EPA's notices were merely locally or regionally applicable actions, because their “legal effect” was limited to the petitioning refneries. 86 F. 4th 1121, 1131–1132 (2023). And, contra EPA, the notices were not based on any determination of nationwide scope or effect. Both EPA's new interpretation and its RIN passthrough theory “fail[ed] to provide the agency with a suffcient basis to adjudicate exemption petitions,” because EPA still looked to refnery-specifc facts before it issued its denials. Id., at 1133. Accordingly, the case properly belonged in the Fifth Circuit, and the majority proceeded to rule against EPA on the merits, vacating and remanding EPA's denials for further consideration. Id., at 1133, 1142.
Judge Higginbotham dissented on venue grounds. In his view, EPA's denial notices were nationally applicable because they applied throughout the country: EPA applied a consist1See, e. g., Orders in American Rfg. Group, Inc. v. EPA, No. 22–1991 (CA3, Aug. 9, 2022), ECF Doc. 23; Countrymark Rfg. & Logistics, LLC v. EPA, No. 22–1878 (CA7, July 20, 2022), ECF Doc. 13; Calumet Mont. Rfg., LLC v. EPA, No. 22–70124 (CA9, Oct. 25, 2022), ECF Doc. 16; Wyoming Rfg. Co. v. EPA, No. 22–9538 (CA10, Aug. 23, 2022), ECF Doc. 26; see also Hunt Rfg. Co. v. EPA, 90 F. 4th 1107, 1113 (CA11 2024).
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ent approach to small refneries spanning “eighteen different states, in the geographical boundaries of eight different circuit courts.” Id., at 1143–1144. And, if the notices were only locally or regionally applicable, then EPA was correct to fnd that the “nationwide scope or effect” exception applied: EPA's statutory interpretation and its passthrough theory were “core determinations” that have nationwide scope or effect in that they “are applicable to all small refneries no matter the location or market in which they operate.” Id., at 1145. We granted certiorari to clarify where venue properly lies. 604 U. S. 997 (2024).
II
Section 7607(b)(1) creates a two-step inquiry for determining venue. At the frst step, we assess whether an EPA action is nationally applicable, or only locally or regionally applicable. If the action is nationally applicable, then our inquiry ends: The case belongs in the D. C. Circuit. If the action is locally or regionally applicable, then we proceed to the second step. There, we ask whether the “nationwide scope or effect” exception applies to override the default rule that locally or regionally applicable actions belong in the regional Circuits. Turning to § 7607(b)(1)'s frst step, we hold that the actions before us are only locally or regionally applicable.
A
To properly categorize EPA's actions at the frst step, we must determine what the relevant “action” is, and what it means for an action to be “nationally applicable” as opposed to “locally or regionally applicable.” Once those principles are clarifed, the categorization here is straightforward.
Because § 7607(b)(1) pegs venue to the scope of the EPA action being challenged, our threshold task is to identify the “action” at issue. To do so, we must read “action” in its Page Proof Pending Publication context. That word means “a thing done.” Webster's Third New International Dictionary 21 (1976) (Webster's); see also Black's Law Dictionary 26 (5th ed. 1979) (Black's) (“something done”). But, we could defne the “thing done” by EPA in different ways. Both EPA's denials of each individual exemption petition and its aggregation of those denials into omnibus notices are in a sense things done. The former is an “activity the Clean Air Act allows the EPA to take,” while the latter is how EPA has chosen to undertake that activity. Kentucky v. EPA, 123 F. 4th 447, 460 (CA6 2024).
To determine which framing matters for purposes of § 7607(b)(1), we look to the example “actions” this provision enumerates. Section 7607(b)(1) lists various examples of EPA actions that qualify as either “nationally applicable” or “locally or regionally applicable.” For both these terms, it then provides a catchall for “any other” “fnal action.” And, we “interpret a `general or collective term' . . . in light of any `common attribute[s]' shared by” statutory examples of that term. Southwest Airlines Co. v. Saxon, 596 U. S. 450, 458 (2022).
The enumerated “actions” in § 7607(b)(1) make clear that this provision “treats each activity the Clean Air Act allows the EPA to take as a distinct `action.' ” Kentucky, 123 F. 4th, at 460. These “actions” all refer to particular exercises of EPA authority undertaken pursuant to particular CAA provisions. For instance, the example of a NAAQS must be understood by reference to § 7409(a), which directs EPA to issue a NAAQS “for each air pollutant,” and thus indicates that each pollutant-specifc standard is its own “action.” Likewise, § 7607(b)(1)'s example of EPA's approval of an “implementation plan under section 7410” must be read in light of § 7410, which makes clear that an implementation plan is a proposal “submitted by a State,” and thus indicates that EPA's approval decision is state specifc. § 7410(a)(2). In each case, the enumerated EPA “action” is defned by refPage Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
erence to the substantive authority under which EPA is acting. See id., at 461.
Accordingly, for both § 7607(b)(1)'s enumerated examples and “any other . . . fnal action taken” by EPA “under this chapter,” we must look to the authorizing CAA provision to identify the “action” at hand. This provision makes the CAA's framing of the relevant “action” controlling, regardless of how EPA chooses to package its decisions in the Federal Register.2 The next question is whether a given action is “nationally applicable” or only “locally or regionally applicable.” Because § 7607(b)(1) does not defne those terms, we presumptively give those terms their ordinary meaning. Burrage v. United States, 571 U. S. 204, 210 (2014). The word “ `[n]ational' contemplates an activity with a nationwide scope,” while the words “local” and “regional” relate only to particular “place[s]” or regions. See Black's 845, 923. And, the word “applicable” requires us to ask what the EPA action in question “ `ha[s] reference to.' ” Kentucky, 123 F. 4th, at 459. Put another way, we ask whether the action “[o]n its face” applies throughout the entire country, or only to particular localities or regions. Sierra Club v. EPA, 926 F. 3d 844, 849 (CADC 2019).
The statutory context supplied by § 7607(b)(1)'s enumerated examples confrms the correctness of this ordinary- meaning approach. The actions that § 7607(b)(1) identifes as “nationally applicable” facially apply nationwide. For example, courts have identifed a NAAQS—a “ `national primary or secondary ambient air quality standard' ”—as “[t]he textbook example of nationally applicable action.” Sierra Club v. EPA, 47 F. 4th 738, 743 (CADC 2022). Conversely, 2The Fifth Circuit therefore erred in summarily accepting EPA's characterization of its omnibus notices as the “two EPA actions” at issue in this case. 86 F. 4th 1121, 1129 (2023); see supra, at 635. Page Proof Pending Publication the actions that the CAA enumerates as “locally or regionally applicable” all have more particularized reach. For instance, “the prototypical `locally or regionally applicable' action” is EPA's approval of a state implementation plan, which, as explained, is state specifc. American Road & Transp. Builders Assn. v. EPA, 705 F. 3d 453, 455 (CADC 2013) (majority opinion of Kavanaugh, J.); supra, at 637. Because catchall “clauses are to be read as bringing within a statute categories similar in type to those specifcally enumerated,” the examples make clear that the ordinary meaning of the terms “nationally applicable” and “locally or regionally applicable” controls. Federal Maritime Comm'n v. Seatrain Lines, Inc., 411 U. S. 726, 734 (1973).3 Applying these principles here, we treat each EPA denial of a refnery's exemption petition as its own “action” for venue purposes. And, EPA's denial of a single refnery's petition plainly is only locally or regionally applicable.
This conclusion follows from how the CAA defnes the submission and evaluation of an RFP exemption petition. The CAA allows “[a] small refnery” to “at any time petition [EPA] for an extension of [its] exemption” from RFP obligations. § 7545(o)(9)(B)(i). EPA, in turn, is to “evaluat[e] a petition” and then “act on any petition submitted . . . not later than 90 days after the date of receipt of the petition.” §§ 7545(o)(9)(B)(ii)–(iii). Thus, the CAA pegs EPA's “ac3Because 42 U. S. C. § 7607(b)(1) requires all actions to be either nationally applicable or locally or regionally applicable, diffcult edge cases may arise. For example, if an EPA action must “formally appl[y]” to “the whole country” to be nationally applicable, Kentucky v. EPA, 123 F. 4th 447, 460 (CA6 2024), then actions could apply to nearly the entire country yet still be locally or regionally applicable, see, e. g., § 7545(i)(4). But, if an action that formally applies to only a subset of the country can be nationally applicable, see ATK Launch Systems, Inc. v. EPA, 651 F. 3d 1194, 1197 (CA10 2011), then line-drawing questions may arise, Kentucky, 123 F. 4th, at 460–462. This case, however, does not present these issues. Page Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
tions” under the exemption provision by reference to each individual exemption petition.
Against this backdrop, our classification decision is straightforward. By defnition, EPA's denial of a single refnery's exemption petition only applies to that refnery, which is a particular entity located in a particular place. That limited reach makes EPA's denials paradigmatically “locally or regionally applicable” actions. See Sierra Club, 926 F. 3d, at 849.
B
We are unpersuaded by EPA's and the intervenors' counterarguments. EPA proffers its omnibus denial notices as the relevant “actions” on the ground that it has the discretion to structure its decisions. According to EPA, it is free to “aggregate similar petitions for joint resolution” in a single “action”—here, its omnibus Federal Register notices—given its right as an agency “ `to fashion [its] own rules of procedure and to pursue methods of inquiry capable of permitting [it] to discharge [its] multitudinous duties.' ” Brief for Petitioner 26–27 (quoting FCC v. Pottsville Broadcasting Co., 309 U. S. 134, 143 (1940)). But, whatever discretion EPA has to manage its internal affairs, Congress conclusively defned the term “action” in § 7607(b)(1) to focus on the specifc statutory authority EPA is exercising.
Tellingly, EPA's position that it can control the unit of “action” used to determine venue lacks any statutory limiting principle. If EPA had free rein to group decisions into a single “action” for venue purposes, then it could bundle even unrelated matters into one Federal Register pronouncement that is, in the aggregate, nationally applicable. Such a possibility would effectively give EPA a veto power over venue under the CAA. We see no reason to read § 7607(b)(1) to permit such gamesmanship. Absent indication that Congress meant to give a party unfettered control over venue, we will not read a venue provision to confer such broad discretion. Cf. Deal v. United States, 508 U. S. 129, 133–134 Page Proof Pending Publication (1993) (disfavoring a reading that would “give a prosecutor unreviewable discretion” as to a sentencing enhancement's applicability).
Because EPA does not dispute that the actions here can be nationally applicable only if it is right that the omnibus denial notices are the relevant “actions,” we need not resolve EPA's remaining arguments. At a minimum, however, we note that EPA's theory for distinguishing between nationally applicable and locally or regionally applicable actions cannot withstand scrutiny. EPA argues that any agency action is nationally applicable if it affects more than one Circuit. But, as we have recognized, the term “nationally applicable” bears its ordinary meaning, supra, at 638, and EPA's view would render actions with a plainly local or regional focus “nationally applicable” simply because the locality or region at issue straddles Circuit lines. For example, some EPA air quality control regions cover metropolitan areas that extend into two Circuits. It would defy credulity to say that an EPA action regarding such a region would therefore be nationally applicable rather than locally or regionally applicable. Cf. Brief for Small Refnery Respondents 41 (“Can there be any doubt that an EPA disapproval of a regional implementation plan for only Region 90 (Metropolitan Kansas City) is a `regionally applicable' action . . . , even though that action touches both the Eighth and Tenth Circuits?”). Whatever the precise line should be, see n. 3, supra, EPA's line cannot be it.
EPA justifes its position based on § 7607(b)(1)'s language equating regional Circuit review with review in “the appropriate circuit.” § 7607(b)(1) (emphasis added). To be reviewable only in a single “appropriate circuit,” EPA contends, the category of “locally or regionally applicable” actions must be limited to those actions affecting only one Circuit. But, in the absence of other evidence, § 7607(b)(1)'s use of the defnite article “the” is too thin a reed to support EPA's conclusion. See 1 U. S. C. § 1 (directing that “words Page Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
importing the singular include and apply to several persons, parties, or things” “unless the context indicates otherwise”). Finally, we fnd no merit in the intervenors' arguments for why the denial of an individual refnery's exemption petition should still be considered nationally applicable. According to the intervenors, the individual denials are nationally applicable because they have follow-on effects for the amount of renewable fuel that must be produced under the RFP and because EPA in issuing the denials announced a new standard for adjudicating exemption petitions. But, again, we determine an action's range of applicability by “look[ing] only to the face of the [action], rather than to its practical effects.” American Road & Transp. Builders Assn., 705 F. 3d, at 456. Any follow-on implications of EPA's denials have no bearing on our analysis of their facial applicability. Cf. Sierra Club, 47 F. 4th, at 744 (“The fact that `EPA's interpretive reasoning' may have `precedential effect in future EPA proceedings . . . does not make [an action] nationally applicable' ”).
III
Because we conclude that EPA's actions were only locally or regionally applicable, we must proceed to the second step of the § 7607(b)(1) inquiry. That is, we ask whether the “nationwide scope or effect” exception applies to override the default of regional Circuit review for locally or regionally applicable actions. This exception channels an action to the D. C. Circuit if (1) it “is based on a determination of nationwide scope or effect,” and (2) “in taking such action [EPA] fnds and publishes that such action is based on such a determination.” § 7607(b)(1). Here, all agree that the second requirement is satisfed: EPA included the necessary fnding in both its April and June denial notices. Supra, at 634–635. Accordingly, the question before us is whether EPA's exemption denials were “based on a determination of nationwide scope or effect.” We conclude that they were.
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A
Here too, we begin by laying out the framework for deciding whether an action is “based on a determination of nationwide scope or effect.” We conclude that this requirement is met if such a determination supplies a core justifcation for EPA's action and that courts should evaluate the basis for EPA's determinations de novo. Applying that framework, we hold that this case is one in which the “nationwide scope or effect” exception applies.
To understand the phrase “based on a determination of nationwide scope or effect,” we again turn to ordinary meaning. Burrage, 571 U. S., at 210. In particular, we look to the plain meaning of this phrase's component words, which are all terms of everyday usage. And, we read these words “in their context and with a view to their place in the overall statutory scheme.” Davis v. Michigan Dept. of Treasury, 489 U. S. 803, 809 (1989).
To begin, a “determination” is the “settling and ending of a controversy,” or “the resolving of a question by argument or reasoning.” Webster's 616; see also 4 Oxford English Dictionary 548 (2d ed. 1989) (“[t]he decision arrived at or promulgated; a determinate sentence, conclusion, or opinion”). In an EPA action, EPA's underlying “determinations are the justifcations [it] gives for the action,” which “can be found in [its] explanation of its action.” Texas v. EPA, 829 F. 3d 405, 419 (CA5 2016).
In turn, a determination's “scope” and “effect” refer, respectively, to its “formal `area' of operation” and to its “ `operative infuence.' ” Kentucky, 123 F. 4th, at 465; see, e. g., American Heritage Dictionary 1164 (1969) (defning “scope” as the “area covered by a given activity or subject”); Webster's 724 (defning “effect” as “something that is produced by an agent or cause”). An agency's determinations are of Page Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
“nationwide” scope or effect if they apply “throughout [the] entire nation.” Id., at 1505. Taken together, an agency action involves determinations of nationwide “scope” if they apply throughout the country “as a legal matter (de jure)” and determinations of nationwide “effect” if they so apply “as a practical one (de facto).” Kentucky, 123 F. 4th, at 465. Of course, nearly all agency actions can be said to involve justifcations of nationwide reach or consequence. For example, most EPA actions presumably rely on EPA's interpretations of its governing statutes.
The key question, then, is the degree of causality contained in the phrase “based on.” And, the meaning of that phrase is context dependent. In many cases, it “indicates a but-for causal relationship.” Safeco Ins. Co. of America v. Burr, 551 U. S. 47, 63 (2007). But-for causation is a comparatively lenient standard, which is met so long as a result “would not have occurred in the absence of—that is, but for—[a party's] conduct.” Burrage, 571 U. S., at 211 (internal quotation marks omitted). In other cases, however, more is needed. Congress sometimes uses phrases such as “based on” to cover only “core” causes amounting to an action's “sine qua non” or “ `gravamen.' ” See, e. g., Fry v. Na poleon Community Schools, 580 U. S. 154, 167, 169 (2017); OBB Personenverkehr AG v. Sachs, 577 U. S. 27, 35 (2015).
Section 7607(b)(1) incorporates the more demanding, “core” understanding of “based on.” This constraint follows from the function of the “nationwide scope or effect” exception as just that—an exception. Congress, after all, is unlikely to intend for an exception to swallow the rule. See Smith & Wesson Brands, Inc. v. Estados Unidos Mexicanos, 605 U. S. 280, 298–299 (2025). Thus, in this context, but-for causation is inadequate: In almost any case, a determination of nationwide scope or effect will be at least a but-for cause of EPA's action, given that any EPA action is downstream of EPA's conclusions as to what its governing statutes permit or require. But, Congress made regional Circuit review the Page Proof Pending Publication default for locally or regionally applicable actions, so we must read the “nationwide scope or effect” exception in a way that preserves regional Circuit review as the norm.
It follows that an EPA action is “based on” a particular determination only if that determination “lie[s] at the core of the agency action,” so as to form the most important part of the agency's reasoning. Texas, 829 F. 3d, at 419. Put more concretely, an EPA action is based on a determination of nationwide scope or effect only if a justifcation of nationwide breadth is the primary explanation for and driver of EPA's action. A determination of nationwide scope or effect does not rise to this level if EPA also relied in signifcant part on other, “intensely factual” considerations, or if the key driver of EPA's action is otherwise debatable. Id., at 421; see also id., at 419 (“The default presumption is that petitions for review of locally or regionally applicable actions `may only be fled in the United States Court of Appeal for the appropriate circuit' ”).
In deciding whether a particular EPA action is “based on a determination of nationwide scope or effect,” courts should assess EPA's reasoning de novo. This standard follows from the structure of the “nationwide scope or effect” exception: The exception applies only “if ” a locally or regionally applicable action is based on a determination of nationwide scope or effect “and if ” EPA, in taking the action, fnds and publishes that the action has this basis. § 7607(b)(1) (emphasis added). In other words, the CAA requires both that EPA deem its action to have a qualifying basis and that the action in fact have this basis. This dual formulation does not naturally suggest that courts should simply give EPA's fnding deference. Cf. Regalado Cuellar v. United States, 553 U. S. 550, 565 (2008) (fnding it “implausible” to infer that Congress intended a particular meaning, where it used a “more complex formulation”).
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The upshot is that courts must “make an independent assessment of the scope of [EPA's] determinations.” Texas, 829 F. 3d, at 421. That is, they should parse the reasoning offered by EPA in taking an action to decide which determinations primarily drove the action. Courts routinely analyze flings to identify their substance, and the language of the “nationwide scope or effect” exception directs them to do the same here.
In so holding, we do not downplay the importance of EPA's role. Because the “nationwide scope or effect” exception can apply only when “EPA so fnds and publishes” that it does, EPA can decide whether the exception is even potentially relevant. Sierra Club, 47 F. 4th, at 746. And, where EPA does invoke the exception, its explanation for doing so will at a minimum focus the courts' assessment of the possible determinations of nationwide scope or effect.4 Thus, EPA's choices will matter, even as courts must assess the bases for EPA's actions themselves.
Applying this framework, we conclude that EPA's denials of the small refneries' exemption petitions were based on determinations of nationwide scope or effect. We agree with EPA's fnding—published in both its April and June denial notices—that its interpretation of the phrase “disproportionate economic hardship” under § 7545(o)(9)(B)(i) and its RIN passthrough theory were determinations of nationwide 4This case does not present the question whether, given principles of issue preservation, courts can forgo consideration of determinations that EPA has not itself identifed as the basis for its action. Cf. SEC v. Chen ery Corp., 318 U. S. 80, 88 (1943) (confning review of agency action “to a judgment upon the validity of the grounds upon which the [agency] itself based its action”). But, we expect this issue to be outcome dispositive only in rare cases. As a practical matter, an action is unlikely to be based on a particular determination where EPA has failed, in promulgating the action, to identify that determination as the relevant determination of nationwide scope or effect.
Page Proof Pending Publication scope or effect that formed the core basis for EPA's denials. Supra, at 634–635.
Both conclusions are clear determinations of nationwide scope or effect: EPA invoked both its statutory interpretation and its passthrough theory in justifying its denials, and both points apply generically to all refneries, regardless of their geographic location. After all, the CAA is a federal statute, and § 7545(o)(9)(B)(i) by its terms applies nationwide. Likewise, EPA's RIN passthrough theory is a fnding about how the national refnery market works. See supra, at 634.
These conclusions also can be deemed the “basis” for EPA's denials here. EPA decided, in light of the foregoing determinations, that it would presumptively deny all the exemption petitions before it. Supra, at 634. It then considered other, refnery-specifc considerations only to confrm that it had no reason to depart from its presumptive disposition. Supra, at 634–635. In this posture, EPA's statutory interpretation and passthrough theory plainly are the most important parts of its reasoning. Or, put another way, where EPA relies on determinations of nationwide scope or effect to reach a presumptive resolution, those determinations qualify as the primary driver of its decision. EPA's confrmatory review of refnery-specifc facts is “[m]erely peripheral” by comparison. Texas, 829 F. 3d, at 419.
Accordingly, we agree with EPA that the “nationwide scope or effect” exception applies here. The Fifth Circuit should have transferred this case.
B
We are unpersuaded by the counterarguments raised by EPA, respondents, the Fifth Circuit, and the dissent.
Although we agree with EPA's bottom-line position that the “nationwide scope or effect” exception applies, we reject its roundabout approach to the word “determination.” EPA argues that “[t]he word `determination' ” in § 7607(b)(1) “sugPage Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
gests a resolution of an unsettled issue,” such that EPA does not make “determinations” when it “applies a previously established agency rule, policy, or interpretation to new . . . circumstances.” Brief for Petitioner 41. We agree with EPA that a “determination” here means the “ `settling and ending of a controversy,' ” ibid.; supra, at 643, but nothing in that term or its use in § 7607(b)(1) suggests that only novel conclusions count. Rather, given § 7607(b)(1)'s focus on the face of the agency action, “determination” is most naturally read to cover any EPA conclusion within the four corners of an action.
Moreover, we do not see how EPA's proposed approach can be squared with its requested disposition. If a “determination” covers only the resolution of an unsettled issue, it is not obvious why EPA's June denials contain any determinations: EPA's June notice purported to “appl[y] the approach . . . adopted in the April” notice. App. to Pet. for Cert. 80a. EPA attempts to avoid this diffculty by proposing a holistic assessment of novelty that considers factors such as “whether EPA announced the rule or policy at roughly the same time as the challenged agency action itself.” Brief for Petitioner 41. But, we do not see how this amorphous test follows even from EPA's view.5 Respondents argue that the word “determination” in § 7607(b)(1) is a term of art, wherein an agency action can trigger the “nationwide scope or effect” exception only if it is undertaken based on a CAA provision that “textually direct[s] EPA to make a `determination' for the entire nation.” Brief for Small Refnery Respondents 32 (emphasis deleted). But, “determination” is “hardly a rarely used word,” and nothing in the CAA's context suggests that Congress meant 5EPA also contends that § 7607(b)(1)'s “based on” language speaks in terms of but-for causation and that courts should assess the basis for EPA's actions deferentially, through arbitrary-and-capricious review. For the reasons already explained, we reject those contentions. Supra, at 644–645.
Page Proof Pending Publication for its use in § 7607(b)(1) to reach only CAA provisions that happen to use some variant of that word. Bruesewitz v. Wyeth LLC, 562 U. S. 223, 235 (2011). Such a limitation would at best lead to arbitrary outcomes, as Congress did not act in a standardized way when using “determination” as opposed to other words. Compare § 7410(k)(3) (not speaking in terms of “determinations”) with § 7410(k)(6) (requiring a “determination” when EPA “[c]orrect[s]” its actions under § 7410(k)(3)). At worst, respondents' approach would render the “nationwide scope or effect” exception meaningless: Respondents have conceded that their term-ofart view may render the exception “a null set, or close to a null set.” Tr. of Oral Arg. 103–104. But, Congress would not have gone to the trouble of creating a superfuous exception, so we will not “force [a] term-of-art defnitio[n]” where it “plainly do[es] not ft.” Gonzales v. Oregon, 546 U. S. 243, 282 (2006) (Scalia, J., dissenting).
The dissent would similarly limit the “nationwide scope or effect” exception to reach only statutorily enumerated determinations, but its arguments fare no better. The dissent highlights that various CAA substantive provisions require EPA to make particular “determinations” before taking an action. Post, at 653–655, 659–660 (opinion of Gorsuch, J.). But, it does not follow that Congress meant to encompass only statutorily enumerated determinations when it spoke generally in the exception of actions “based on a determination of nationwide scope or effect.” § 7607(b)(1) (emphasis added). And, although some statutes “ `distinguis[h] between “considerations” that inform [a] “determination” and the “determination” itself,' ” post, at 659–660 (quoting Commissioner v. Zuch, 605 U. S. 422, 429 (2025); alterations in original), statutes like the one in Zuch use “determination” to refer to an agency's ultimate decision, see id., at 428–429. In asking whether a determination supplies the basis for an EPA action, § 7607(b)(1) uses the term in a different sense. Likewise, the dissent's concern that our test could be diffcult for Page Proof Pending Publication EPA v. CALUMET SHREVEPORT REFINING, L.L.C.
“lower courts and lawyers to apply” is not a problem of our creation. Post, at 660. Insofar as the reticulated venue framework that Congress enacted creates diffculty for courts or litigants, “it is a problem for Congress, not one that federal courts can fx.” Lewis v. Chicago, 560 U. S. 205, 217 (2010).
Finally, we are unpersuaded by respondents' argument, accepted by the Fifth Circuit, that the “nationwide scope or effect” exception is inapplicable in light of EPA's consideration of refnery-specifc facts. That exception requires that an EPA action be “based on” a determination of nationwide scope or effect, in contrast to another part of § 7607(b)(1) where Congress used the phrase “based solely on.” Accordingly, EPA's consideration of local facts does not preclude its invocation of the exception, either generally or here. So long as a determination of nationwide scope or effect served as the primary driver of EPA's action, other, more “peripheral” determinations “are not relevant” for venue purposes. Texas, 829 F. 3d, at 419.
* * * We agree with the Fifth Circuit that EPA's actions here are only locally or regionally applicable, although we clarify that the relevant actions are EPA's individual denials of the small refneries' exemption petitions. But, under a proper understanding of § 7607(b)(1), the “nationwide scope or effect” exception applies, and the case belongs in the D. C. Circuit. The Fifth Circuit therefore erred in denying EPA's request to transfer. The judgment of the Court of Appeals is vacated, and the case is remanded for further proceedings consistent with this opinion.
It is so ordered.