                             UNITED STATES DISTRICT COURT
                             FOR THE DISTRICT OF COLUMBIA


   CENTER FOR BIOLOGICAL
   DIVERSITY, et al.,

                           Plaintiffs,

            v.

   UNITED STATES ENVIRONMENTAL
   PROTECTION AGENCY,                                      Civil Action 10-00985 (HHK)

   and

   LISA JACKSON, Administrator of the
   Environmental Protection Agency,

                           Defendants.


                           MEMORANDUM OPINION AND ORDER

         Plaintiffs Center for Biological Diversity, Center for Food Safety, Friends of the Earth,

International Center for Technology Assessment, and Oceana (collectively, “plaintiffs”) bring

this action against the U.S. Environmental Protection Agency and its Administrator, Lisa Jackson

(collectively, “EPA”), seeking to compel agency action with regard to the regulation of emissions

by non-road vehicles and engines, including marine vessels and aircraft, under the Clean Air Act

(“the Act”), 42 U.S.C. § 7401 et seq. Before the Court are two joint motions to intervene in

support of EPA, the first [#10] on behalf of the Air Transport Association of America (“ATA”)

and the National Business Aviation Association (“NBAA”) and the second [#12] on behalf of the

Aerospace Industries Association of America (“AIA”) and the General Aviation Manufacturers

Association (“GAMA”). Because these motions raise nearly identical issues, the Court addresses

them together, referring to all of the putative intervenors collectively as “movants.” Upon
consideration of the motions, the oppositions thereto, and the record of this case, the Court

concludes that both motions should be denied.


                                       I. BACKGROUND

A.     The Clean Air Act and Aircraft Emissions Regulations

       The Clean Air Act gives EPA the authority to regulate “air pollutants,” a category that it

defines very broadly. See 42 U.S.C. § 7402(g); Massachusetts v. EPA, 549 U.S. 497, 506–10

(2007) (describing the history of the Act and efforts to address climate change). The Act also

creates a specific regulatory scheme for emissions from “nonroad” engines and vehicles (other

than train locomotives), including aircraft. See 42 U.S.C. § 7547(a). Under that framework,

EPA “shall” conduct a study of emissions from such sources, id. § 7547(a)(1), and determine

whether they are “significant contributors to ozone or carbon monoxide concentrations in more

than 1 area which has failed to attain the national ambient air quality standards for ozone or

carbon monoxide.” Id. § 7547(a)(2). If that determination is affirmative, EPA must promulgate

appropriate regulations. Id. § 7547(a)(3).

       EPA may also promulgate regulations if it determines that any other emissions from such

sources “significantly contribute to air pollution which may reasonably be anticipated to

endanger public health or welfare.” Id. § 7547(a)(4). Similarly, the Act states that EPA “shall,

from time to time, issue proposed emission standards applicable to the emission of any air

pollutant from any class or classes of aircraft engines which in [its] judgment causes, or

contributes to, air pollution which may reasonably be anticipated to endanger public health or




                                                 2
welfare.” Id. § 7571(a)(2)(A). These predicate determinations are commonly referred to as

“endangerment findings.”

       Pursuant to its authority under the Act, EPA has adopted aircraft emission standards

“covering certain criteria pollutants or their precursors and smoke; these standards do not

currently regulate emissions of CO2 and other [greenhouse gases].” Regulating Greenhouse Gas

Emissions Under the Clean Air Act, 73 Fed. Reg. 44,354, 44,469 (July 30, 2008). In setting

emissions standards, EPA has historically cooperated with the Federal Aviation Administration

and the International Civil Aviation Organization, id., which is an agency of the United Nations

charged with fostering the safe and orderly growth of international civil aviation.

B.     Plaintiffs’ Petitions

       Between October 2007 and January 2008, plaintiffs submitted three petitions to EPA,

asking it to use its authority under the provisions described above to regulate greenhouse gas

emissions from marine vessels, aircraft, and other nonroad vehicles. Compl. ¶¶ 48–50. EPA

subsequently issued an Advance Notice of Proposed Rulemaking regarding greenhouse gas

emissions, see 73 Fed. Reg. 44,354, but plaintiffs assert that it was not responsive to their

petitions because it failed to determine whether greenhouse gas emissions from these sources

endanger public health or welfare or to establish a plan for regulating such emissions. Compl.

¶¶ 55–59. Accordingly, plaintiffs filed a notice of intent to sue as required by the Act, Compl.

¶ 53; see 42 U.S.C. § 7604(a), (b)(1), and commenced this action, seeking to compel EPA to

respond to their petitions. Shortly thereafter, movants, who represent numerous manufacturers




                                                  3
and operators of aircraft, aircraft components, and aircraft engines,1 sought leave to intervene in

support of EPA. See AIA & GAMA’s Mem. in Supp. of Mot. for Leave to Intervene (“AIA &

GAMA Mem.”); ATA & NBAA’s Mem. in Supp. of Mot. for Leave to Intervene (“ATA &

NBAA Mem.”). EPA takes no position on movants’ intervention; plaintiffs oppose it.


                                          II. ANALYSIS

       Movants seek leave to intervene in this action on two grounds: they assert that they are

entitled to intervene as of right under Federal Rule of Civil Procedure 24(a); they alternatively

seek permissive intervention under Rule 24(b). Plaintiffs respond that movants do not meet

either intervention standard, and further assert that movants may not intervene here because they

lack standing to do so. The Court first addresses intervention as of right.

A.     Intervention as of Right Under Rule 24(a)

       Movants assert that they are entitled to intervene as of right in this action because they

have made the necessary showing under Rule 24(a).2 Plaintiffs disagree, and further challenge

movants’ Article III standing to intervene. Movants respond that they do not need to establish




       1
               AIA represents aerospace and defense manufacturers; GAMA represents aircraft
and aircraft component manufacturers; ATA represents air passenger and cargo carriers; and
NBAA represents companies of various types that own and operate general aviation aircraft.
       2
                Intervention as of right under Rule 24(a) turns on four factors: (1) the timeliness
of the motion; (2) whether the applicant claims an interest relating to the property or transaction
which is the subject of the action; (3) whether the applicant is so situated that the disposition of
the action may as a practical matter impair or impede the applicant’s ability to protect that
interest; and (4) whether the applicant’s interest is adequately represented by existing parties.
See FED . R. CIV . P. 24(a)(2); Fund for Animals, Inc. v. Norton, 322 F.3d 728, 731 (D.C. Cir.
2003).

                                                  4
standing in order to intervene as of right. Because standing goes to the Court’s jurisdiction, see

Sierra Club v. EPA, 292 F.3d 895, 898 (D.C. Cir. 2002), the Court turns first to that issue.

       1.      Putative Intervenors as of Right Must Establish Article III Standing in this
               Circuit

       Movants argue that the standing inquiry is redundant where a party seeks to intervene as

of right “because an intervenor who satisfies Rule 24(a) will also have Article III standing.”

ATA & NBAA’s Reply to Pl.’s Opp’n (“ATA & NBAA Reply”) at 2; accord AIA & GAMA

Mem. at 10 n.8. They would thus have the Court set aside the standing inquiry and focus solely

on the Rule 24(a)(2) intervention as-of-right factors. Movants base this argument on the D.C.

Circuit’s opinion in Roeder v. Islamic Republic of Iran, 333 F.3d 228 (D.C. Cir. 2003), which

acknowledged a split among the circuits as to whether prospective intervenors must establish

standing and discussed certain difficulties that can arise when applying the standing inquiry to

such cases. Id. at 233–34. In so doing, the Roeder court suggested that “[w]ith respect to

intervention as of right in the district court, the matter of standing may be purely academic.” Id.

at 233; see also Akiachak Native Cmty. v. U.S. Dep’t of Interior, 584 F. Supp. 2d 1, 7 (D.D.C.

2008) (citing Roeder for the proposition that a Rule 24 intervenor will always have Article III

standing). Movants, however, attribute too much significance to this language. Roeder did not

depart from the D.C. Circuit’s clearly established rule that “an intervenor must also establish its

standing under Article III of the Constitution.” Roeder, 333 F.3d at 233 (citing Fund for

Animals, Inc. v. Norton, 322 F.3d 728, 731–32 (D.C. Cir. 2003); Bldg. & Constr. Trades Dep’t v.

Reich, 40 F.3d 1275, 1282 (D.C. Cir. 1994)).




                                                 5
       First, the Roeder court itself engaged in a standing inquiry, albeit a very brief one. See id.

at 233–34. Second, as a three-judge panel, the Roeder court had no authority to abrogate the

clear rule announced in prior three-judge panel cases like Fund for Animals and Building and

Construction Trades. See LaShawn A. v. Barry, 87 F.3d 1389, 1395 (D.C. Cir. 1996) (en banc).

Third and finally, subsequent decisions of the D.C. Circuit and this district flatly state that

putative intervenors must meet Article III’s standing requirements. See, e.g., United States v.

Phillip Morris USA, Inc., 566 F.3d 1095, 1146 (D.C. Cir. 2009); City of Naples Airport Auth. v.

FAA, 2004 WL 1080160, at *1 (D.C. Cir. May 13, 2004); Jones v. Prince George’s Cnty., Md.,

348 F.3d 1014, 1017 (D.C. Cir. 2003); Wildearth Guardians v. Salazar, 2010 WL 4923884, at *6

(D.D.C. Dec. 6, 2010); In re Endangered Species Act Section 4 Deadline Litig., 2010 WL

3386392, at *3 (D.D.C. Aug. 27, 2010). Thus, the Court cannot eschew the standing inquiry

here, and will determine whether movants have Article III standing to intervene.

       2.      Movants Cannot Establish Article III Standing

       In Lujan v. Defenders of Wildlife, 504 U.S. 555 (1992), the Supreme Court explained that

“the irreducible constitutional minimum of standing” contains three elements: (1) injury-in-fact,

(2) causation, and (3) redressability. Id. at 560–61. A would-be plaintiff or intervenor must

show all three. Id. at 561. To establish the existence of an injury-in-fact, a party must show an

invasion of a legally protected interest that is “concrete and particularized” and “actual or

imminent, not ‘conjectural’ or ‘hypothetical.’” Id. at 560 (quoting Whitmore v. Arkansas, 495

U.S. 149, 155 (1990)). Where the alleged injury has not yet occurred, the necessary level of

imminence is “somewhat elastic,” but requires that the injury be “‘certainly impending.’” Id. at

564 n.2 (quoting Whitmore, 495 U.S. at 158 (emphasis added)). To establish causation, the party


                                                  6
must show that the injury complained of is “‘fairly . . . trace[able] to the challenged action

. . . and not . . . th[e] result [of] the independent action of some third party not before the court.’”

Id. at 560 (alterations in original) (quoting Simon v. E. Ky. Welfare Rights Org., 426 U.S. 26,

41–42 (1976)). Finally, “it must be ‘likely,’ as opposed to merely ‘speculative,’ that the injury

will be ‘redressed by a favorable decision.’” Id. at 561 (quoting Simon, 426 U.S. at 38, 43).

        Here, then, movants must demonstrate a causal connection between a judgment by this

Court for plaintiffs and a concrete and imminent injury-in-fact to themselves.3 See Fund for

Animals, 322 F.3d at 733. For the purpose of this analysis, the Court will assume that plaintiffs

will prevail on the merits of this action and obtain the relief they seek: responses to their

petitions, endangerment findings to be undertaken by EPA within 90 days, and the initiation of

rulemakings (or explanations for a lack thereof) if the endangerment findings are affirmative. Cf.

id. (analyzing the putative intervenor’s standing with relation to the relief sought by the

plaintiffs).

        Movants identify two elements of the relief sought by plaintiffs that they believe will

cause them injuries sufficiently concrete to confer standing here: the imposition of new aircraft

emissions standards, and the development of such standards on an accelerated timetable.4


        3
                The Court assumes that if movants can establish the first two elements of
standing, the redressability prong will also be satisfied; after all, if movants show that a judgment
by this Court for plaintiffs will directly cause the injury they identify, they will necessarily have
shown that a judgment against plaintiffs would likewise redress that injury. Cf. Fund for
Animals, 322 F.3d at 733 (“This injury [identified by the prospective intervenor] is fairly
traceable to the regulatory action . . . that the [plaintiff] seeks [to compel]. And it is likely that a
decision favorable to the [intervenor] would prevent that loss from occurring.”).
        4
                Presumably because of their misconception, described above, that standing need
not be established in intervention-as-of-right cases, movants devote little attention to standing in
their filings. Accordingly, in analyzing movants’ standing arguments, the Court also draws on

                                                   7
Plaintiffs rejoin that the former is too hypothetical to confer standing and the latter will not result

in any injury to movants. The Court addresses each in turn, finding neither to support movants’

standing here.



                 a.    The Imposition of New Aircraft Emissions Regulations

       Movants assert that aircraft emissions standards “have enormous consequences for

commercial and business aircraft operators in terms of investment in aircraft, asset value of the

existing fleet, maintenance support, and the conduct of operations.” ATA & NBAA Mem. at 4;

see also AIA & GAMA Mem. at 5–6. The Court does not doubt, and plaintiffs do not contest,

the accuracy of this assertion. Further, this type of injury — economic harm resulting from

government action that changes market conditions — is routinely recognized as sufficiently

concrete to constitute an injury-in-fact for standing purposes. See, e.g., Clinton v. City of New

York, 524 U.S. 417, 432–33 (1998). Plaintiffs argue, however, that the implementation and

enforcement of new emissions standards — and thus, the economic consequences thereof — are

too hypothetical and too far removed from a judgment of this Court to constitute a “certainly

impending,” causally connected injury for standing purposes. Plaintiffs are correct.

       In order for a judgment of this Court in plaintiffs’ favor to result in the economic harms

identified by movants, several contingencies would have to come about: EPA would have to

make endangerment findings; those findings would have to be positive; EPA would have to

initiate a rulemaking; that rulemaking would have to result in emissions standards that forced




their arguments, directed at the Rule 24(a)(2) standard, that their interests would be impaired by a
judgment for plaintiffs.

                                                   8
movants to spend money. The parties dispute the extent to which each of these steps must

necessarily flow from the previous one, but the only event that is guaranteed to flow directly from

a judgment of this Court is the first. The rest are all contingent upon an affirmative

endangerment finding by EPA, an outcome that will turn not on any order of this Court but rather

on the application of agency expertise to scientific evidence.5   Thus, it cannot be said that if the

Court finds for plaintiffs, the economic harm that movants predict will be “‘certainly

impending.’” Lujan, 504 U.S. at 564 n.2 (quoting Whitmore, 495 U.S. at 158 (emphasis added)).

Rather, such an outcome would remain “hypothetical” at least until an affirmative endangerment

finding was made. Id. at 560 (quoting Whitmore, 495 U.S. at 155) (internal quotation marks

omitted). By the same token, the intervening contingency of the endangerment finding prevents

the economic harm asserted by movants from being “fairly . . . trace[able]” to a judgment in

favor of plaintiffs. Id. (quoting Simon, 426 U.S. at 41) (internal quotation marks omitted). This

alleged injury thus fails both the injury-in-fact and causation prongs of the standing test.

       None of the cases cited by movants alters this analysis. Each one involved a course of

agency action that had advanced beyond the preliminary steps that plaintiffs seek to trigger here.

For example, in Fund for Animals, 322 F.3d 728, the plaintiffs sought to reverse a prior

determination by the Fish and Wildlife Service (“FWS”) that a particular Mongolian sheep was

not “endangered” under the Endangered Species Act. The D.C. Circuit held that the government

of Mongolia had standing to intervene in support of FWS, finding that Mongolia had established



       5
               See, e.g., EPA Endangerment and Cause or Contribute Findings for Greenhouse
Gases Under Section 202(a) of the Clean Air Act, 74 Fed. Reg. 18,886, 18,904 (Apr. 24, 2009)
(explaining that an endangerment finding in the greenhouse gas context was based on “the
product of decades of research by thousands of scientists from the U.S. and around the world”).

                                                  9
an imminent injury-in-fact by showing that a listing of the animal as “endangered” would result

in restrictions on the import of the animals into the United States and thus a drop in tourist

income from American hunters in Mongolia. See id. at 733–34. The key difference between

Fund for Animals and this case is that in Fund for Animals, the predicate determination in

question had already been made (in the negative) and the plaintiffs were seeking to have the

Court reverse it. The same was true in County of San Miguel, Colorado v. MacDonald, 244

F.R.D. 36, 44–45 (D.D.C. 2007) (allowing intervention by landowners where the plaintiffs

sought to reverse a decision by FWS not to list as “endangered” an animal species that lived on

the landowners’ property).6 Here, by contrast, plaintiffs only ask the Court to require EPA to

make the determination, not to reach any particular result.7

       A much closer analogue to this case can be found in In re Endangered Species Act

Section 4 Deadline Litigation, 2010 WL 3386392, at *3 (D.D.C. Aug. 27, 2010) [hereinafter In

re ESA Litigation]. There, the plaintiffs (some of whom are plaintiffs in this case) alleged that


       6
                Likewise, the Court does not find Military Toxics Project v. EPA, 146 F.3d 948
(D.C. Cir. 1998), or American Horse Protection Association, Inc. v. Veneman, 200 F.R.D. 153
(D.D.C. 2001), to be analogous. In both of those cases, the plaintiffs were challenging the
validity of regulations already in place, the abrogation of which would necessarily result in new
rulemakings to replace them. Here, as described above, a ruling by this Court for plaintiffs
cannot result in any rulemaking that would change the regulatory status quo unless followed by
an affirmative endangerment finding by EPA. Finally, Natural Resources Defense Council v.
Costle, 561 F.2d 904 (D.C. Cir. 1977), on which movants heavily rely, is inapposite: that case
dealt only with intervention and made no mention of standing (and predated the D.C. Circuit’s
rule that would-be intervenors must show standing).
       7
                Movants are surely right that plaintiffs seek to have EPA make the endangerment
findings because they hope for an affirmative result, which would in turn trigger rulemaking. See
ATA & NBAA Reply at 3–4. Even so, plaintiffs’ hope that this suit will cause the eventual
regulation of aircraft emissions does not make it so: the intervening contingency of the
endangerment finding, rather than plaintiffs’ aspirations, governs the imminence and causation
inquiries here.

                                                 10
FWS had failed to determine, before a statutorily imposed deadline, whether a particular species

of salamander was endangered, and sought “an order declaring that the FWS failed to comply

with its statutorily-mandated deadline and . . . requiring the Secretary to make the required

finding by a date certain.” Id. at *2. A corporation called TRC, which owned land comprising a

portion of the salamander’s habitat, sought to intervene on behalf of FWS, arguing that “the

outcome of the FWS listing determination for this species may precipitate restrictions on the use

of its land and business operations.” Id. at *3.

        The In re ESA Litigation court concluded that the corporation had failed to establish

Article III standing, stating:

        TRC’s alleged injury is based entirely on the potential substantive outcome of the
        FWS’s listing determination for the Tehachapi slender salamander, which is not
        before this Court. The case before this Court deals only with the FWS’s alleged
        failure to complete a preliminary step in the listing process within the time period
        required by law. Because this Court will issue no order directly impacting TRC’s use
        of its property, TRC’s claims of injury from restrictions on its property use and
        business operations bear no relation to the present action.

Id. at *4 (emphasis added). The same is true here. Movants’ alleged injury “is based entirely on

the potential substantive outcome of [EPA’s endangerment] determination . . . which is not

before this Court.” Id. Accordingly, that injury is neither certainly impending nor fairly

traceable to any judgment of this Court in the present action. See Lujan, 504 U.S. at 560, 564

n.2; In re ESA Litig., 2010 WL 3386392, at *4.

                b.      The Accelerated Timetable Sought by Plaintiffs

        In an effort to narrow the causal gap between a judgment of this Court for plaintiffs and

any concrete harm to themselves, movants next assert that they would be harmed by the

accelerated timetable sought by plaintiffs, under which EPA would be required to issue


                                                   11
endangerment findings within 90 days of the Court’s judgment. Movants fear that the resulting

regulations could impose “significant costs which may or may not be practical, realistic, or

justified.” AIA & GAMA Mem. at 13. Plaintiffs respond that they do not in fact seek an

accelerated timetable for the promulgation of regulations, only for the predicate endangerment

findings. Thus, plaintiffs aver, any regulations that eventually result will have had the benefit of

full deliberation by EPA and participation by movants. Plaintiffs have the stronger argument.

       Movants appear to argue that they would be harmed both by a rushed rulemaking process

and by an accelerated endangerment finding. The former, however, is not among the relief

sought by plaintiffs. Rather, plaintiffs merely ask the Court to declare that if EPA makes an

affirmative endangerment finding, it must “initiate rulemaking” pursuant to the Clean Air Act.

Compl. at 29 (emphasis added). No timetable for the initiation or completion of such a

rulemaking is requested.8 Thus, there appears to be no basis for movants’ fears that a judgment

of this Court in favor of plaintiffs would result in regulations promulgated too quickly for them

to have significant input. Cf. In re ESA Litig., 2010 WL 3386392, at *4 (rejecting the

prospective intervenor’s argument that it would be harmed by the timing of the decision that the

plaintiffs sought to compel FWS to make).

       Plaintiffs do, however, seek an accelerated timetable for the predicate endangerment

findings: they ask the Court to order EPA to conduct endangerment findings within 90 days of



       8
                 Indeed, the paragraphs in the prayer for relief that address section 213(a) of the
Clean Air Act ask the Court to require that, after an affirmative endangerment finding, EPA
either “initiate rulemaking . . . or explain the reasons for its decision not to act.” Compl. at 29
(emphasis added). Thus, with regard to two of their three claims, plaintiffs do not seek any
mandated rulemaking at all, let alone a rulemaking with an accelerated timetable like that
described by movants.

                                                 12
the Court’s judgment. Even so, movants fail to clarify why such an outcome would support

standing here. They assert that 90 days is not a sufficient length of time for EPA to adequately

consider the aviation industry’s “many technical, legal, and practical complexities.”9 AIA &

GAMA Mem. at 13. They do not explain, however, how such an outcome would actually harm

them. If they mean to suggest that a shortened endangerment finding period would increase the

likelihood of an affirmative finding, thus triggering unnecessary rulemaking, they do not explain

how or why that is the case. Further, for such an argument to support standing, movants would

need to show both that a 90-day timetable would constitute an omission of a statutorily required

procedure and that it is “substantially probable” that such an omission would cause them an

injury-in-fact. Fla. Audubon Soc’y v. Bentsen, 94 F.3d 658, 664–65 (D.C. Cir. 1996). They have

not attempted to show the former at all, and have failed to establish the latter.10 Accordingly, the

timetable elements of the relief sought by plaintiffs cannot create standing for movants to

intervene here.

       3.         Movants May Not Intervene as of Right Because They Lack Standing




       9
                Movants do not explain why these policy issues are appropriate factors for EPA to
consider in determining whether emissions of greenhouse gases from aircraft engines cause or
significantly contribute to air pollution that may reasonably be anticipated to endanger public
health or welfare in the meaning of the Clean Air Act. See Massachusetts v. EPA, 549 US 497,
533 (2007) (explaining that regulatory “policy judgments . . . have nothing to do with whether
greenhouse gas emissions contribute to climate change” and holding that it was error for EPA to
rely on such considerations in lieu of reaching an endangerment determination or explaining why
it was unable to do so).
       10
               The same requirement would be fatal to any argument that the shortened
endangerment finding window itself caused an injury-in-fact to movants. See Fla. Audubon
Soc’y, 94 F.3d at 664.

                                                 13
       Because movants fail to identify an injury that is concrete, certainly impending, and fairly

traceable to a judgment of the Court, they cannot establish standing and may not intervene as of

right in this action. The Court will thus eschew any separate consideration of the Rule 24(a)

factors, but it notes that much of the standing analysis above also applies to the question of

whether movants have a protectable interest in the outcome of this action within the meaning of

Rule 24(a)(2). Cf. In re ESA Litig., 2010 WL 3386392, at *4 (finding that where intervenor-

applicants lacked standing, they also lacked a legally protectable interest under Rule 24(a)(2),

which requires “that the intervenor will either gain or lose by the direct legal operation and effect

of the judgment” (quoting United States v. Am. Tel. & Tel. Co., 642 F.2d 1285, 1291–92 (D.C.

Cir.1980)) (internal quotation marks omitted)).

B.     Permissive Intervention Under Rule 24(b)

       In the alternative, movants seek permissive intervention under Rule 24(b). Under that

provision, the Court may allow timely intervention11 if the movant has a conditional statutory

right to intervene or “a claim or defense that shares with the main action a common question of

law or fact.” FED . R. CIV . P. 24(b)(1)(A), (B). The D.C. Circuit has adopted a flexible reading of

Rule 24(b)’s “claim or defense” language, “allowing intervention even in ‘situations where the

existence of any nominate claim or defense is difficult to find.’” EEOC v. Nat’l Children’s Ctr.,

146 F.3d 1042, 1046 (D.C. Cir. 1998) (quoting Nuesse v. Camp, 385 F.2d 694, 704 (D.C. Cir.

1967)). Even where a party clears the claim-or-defense threshold, the Court has “considerable

latitude” to grant or deny intervention based on the particular circumstances of the case. Crow

Tribe of Indians v. Norton, 2006 WL 908048, at *2 (D.D.C. Apr. 7, 2006) (citing Nat’l


       11
               Plaintiffs do not dispute that movants’ motions to intervene were timely.

                                                  14
Children’s Ctr., 146 F.3d at 1046, 1048); see also Stringfellow v. Concerned Neighbors in

Action, 80 U.S. 370, 382 n.1 (1987) (“[T]he decision whether to grant permissive intervention

resides largely in the discretion of the district court.”).

        At the outset, the Court notes that there is substantial confusion as to whether the D.C.

Circuit’s reading of Rule 24(b) allows for permissive intervention where the would-be intervenor

lacks Article III standing. See In re Vitamins Antitrust Class Actions, 215 F.3d 26, 31–32 (D.C.

Cir. 2000) (noting that prior cases employ a very broad reading of Rule 24(b) but also require

that permissive intervenors have an independent basis for subject-matter jurisdiction, resulting in

“uncertainty over whether standing is necessary for permissive intervention” (citing Nat’l

Children’s Ctr., 146 F.3d at 1045–46)); accord. Rubin v. Islamic Republic of Iran, 2010 WL

3501554, at *3 n.4 (D.D.C. Sept. 08, 2010). If Article III standing is required, then it is, for the

reasons explained above, beyond the Court’s power to allow movants to intervene here. The

Court, however, need not determine whether that is the case, because it concludes that even if

movants meet the “claim or defense” standard, they should not be allowed to intervene.

        In exercising its discretion under Rule 24(b), the Court must consider “whether the

intervention will unduly delay or prejudice the rights of the original parties,” FED . R. CIV . P.

24(b)(3), and may also consider “whether parties seeking intervention will significantly

contribute to . . . the just and equitable adjudication of the legal question presented.” Aristotle

Int’l, Inc. v. NGP Software, Inc., 714 F. Supp. 2d 1, 18 (D.D.C. 2010) (quoting H.L. Hayden Co.

v. Siemens Med. Sys., Inc., 797 F.2d 85, 89 (2d Cir. 1986) (alteration in original)). It is on these

grounds that the Court concludes that movants should not be allowed to intervene here.




                                                   15
        Movants’ concern over this case is obvious: if plaintiffs succeed in compelling EPA to

undertake endangerment findings with regard to aircraft emissions, those findings might be

positive. If so, EPA may promulgate regulations that could impose financial burdens on

movants. What is less obvious is movants’ potential contribution to the “‘just and equitable

adjudication of the legal question presented.’” Aristotle, 714 F. Supp. 2d at 18 (quoting H.L.

Hayden Co., 797 F.2d at 89). Movants argue persuasively that they have substantial expertise

and a unique perspective regarding the manufacture and operation of aircraft and the engines

thereof. Contrary to movants’ assertions, however, aircraft and their engines are not at issue in

this case. Rather, the Court has been asked to determine whether EPA has an enforceable

obligation to make the findings sought by plaintiffs and, if so, whether it has breached that

obligation. With regard to these questions, movants offer no more than conclusory assertions

that their participation will be helpful, and fail to demonstrate an “‘ability to contribute to the full

development of the factual and legal issues presented.’” City of Williams v. Dombeck, 2000 WL

33675559, at *4 (D.D.C. Aug. 17, 2000) (quoting Humane Soc’y v. Clark, 109 F.R.D. 518, 521

(D.D.C. 1985)); cf. Envtl. Def. Fund v. Thomas, 1985 WL 6050, at *6–7 (D.D.C. Oct. 29, 1985)

(denying permissive intervention where industry groups sought to intervene in a suit over the

timing with which EPA would promulgate certain regulations, on the ground that their

“substantial experience and technical expertise as an industry . . . ha[d] no bearing on the legality

of the timetable process here in dispute”).

        Thus, even if movants’ interest in this case is sufficiently concrete to constitute “a claim

or defense” under Rule 24(b) — and if their lack of Article III standing does not otherwise

preclude permissive intervention — “intervening in this essentially procedural matter is not an


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appropriate mechanism for [movants] to protect [their] substantive interests.” In re ESA

Litigation, 2010 WL 3386392, at *5. Accordingly, the Court concludes that movants’ motions

must be denied.

                                      IV. CONCLUSION

               For the foregoing reasons, movants’ motions to intervene must be denied.

Accordingly, it is this 11th day of April 2011 hereby

       ORDERED that ATA and NBAA’s motion to intervene in support of defendant [#10] is

DENIED; and is further

       ORDERED that AIA and GAMA’s motion to intervene in support of defendant [#12] is

DENIED.


                                                        Henry H. Kennedy, Jr.
                                                        United States District Judge




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