While other federal circuits have long had legal tests, standards, and procedural rules for addressing appellant, appellee, and even intervenor and amici standing, the Federal Circuit was a new entrant with the Phigenix decision. Recent cases from the Supreme Court, the other circuits, and recent Federal Circuit panels reveal two schools of thought for standing on appeal: whether it must be established by one or all the parties. The former is the more just and sensible approach and is more in line with Supreme Court precedent, and the Federal Circuit has already signaled it will—as it should—adopt that approach.

Standing Generally

Article III standing is the most fundamental prerequisite for federal litigants. It constitutionally ensures that federal courts rule only on “cases or controversies” and avoid “advisory opinions.”

The Constitution limits the power of federal courts. Pursuant to Article III, federal courts may only adjudicate “Cases” and “Controversies.”¹ The Supreme Court has outlined doctrines establishing Article III limits on the federal courts’ jurisdiction—as limited to disputes seeking to “redress or prevent actual or imminently threatened injury to persons caused by private or official violation of law.”² These doctrines, such as standing, ripeness, and mootness, demarcate the justiciable from the nonjusticiable—thus defining the scope of the authority of Article III courts.³

Standing to sue was first hinted at in Fairchild v. Hughes.⁴ As the doctrine grew, courts became better at couching the requirements in constitutional doctrine, most commonly citing the requirements of the Tenth Amendment and the separation of powers.⁵ Indeed, federal courts may not make broad policy-based decisions; rather, the framers created them to resolve real-world factual disputes based on established law.

To demonstrate the “irreducible constitutional minimum of standing,” plaintiffs must meet three requirements.⁶ First, the plaintiff must demonstrate an “injury in fact” that is both concrete and particularized, and actual or imminent (rather than merely conjectural or hypothetical). Second, the injury must be “fairly traceable” to the challenged action. Third, the injury must be “redressable” by a favorable judicial decision.

Even when met, prudence may permit a court to refuse to hear some legal claims. This limitation, “prudential standing,” generally comprises three distinct bars: “the general prohibition on a litigant’s raising another person’s legal rights, the rule barring adjudication of generalized grievances more appropriately addressed in the representative branches, and the requirement that a plaintiff’s complaint fall within the zone of interests protected by the law invoked.”⁷ Congress, by statute, may obviate any prudential standing by “grant[ing] an express right of action to persons who otherwise would be barred by prudential standing rules.”⁸ Prudential limits on standing are “essentially matters of judicial self-governance.”⁹

To be sure, “Congress may enact statutes creating legal rights, the invasion of which creates standing, even though no injury would exist without the statute.”¹⁰ But their ability to do so is fraught with interpretive challenge. In Lujan, the Supreme Court held that Congress could relax the requirements of standing through procedural rights. As expressed by Justice Kennedy in concurrence, “Congress has the power to define injuries and articulate chains of causation that will give rise to a case or controversy where none existed before.”¹¹

Thus, while Article III standing is not required for proceedings before administrative agencies, including the U.S. Patent and Trademark Office (USPTO),¹² “the starting point for a standing determination for a litigant before an administrative agency . . . is the statute that confers standing before that agency.”¹³ Congress thus can grant, and has granted, standing to virtually anyone to participate in some types of federal agency proceedings.¹⁴

Nonetheless, constitutional standing still applies on appeal to the federal courts.¹⁵ Both standing to sue and standing to appeal require the same three elements: injury-in-fact, causation, and redressability.

Courts thus enforce the standing requirement when a party appeals from an administrative agency to an Article III court. To wit, the D.C. Circuit frequently addresses standing on appeal for the first time because that court has jurisdiction over direct appellate review of several agencies, including the Federal Communications Commission (FCC),¹⁶ as do other appeals courts.¹⁷

Relevant here, the AIA authorizes anyone who is not the patent owner to seek cancellation of patent claims through its post-grant proceedings. Any petitioner is well within its statutory rights to seek review and cancellation of a patent before the USPTO, but the petitioner must independently establish Article III standing in a subsequent appeal.

Appellate Standing from Agency Action at the Federal Circuit

Prior to 2014, the Federal Circuit had only rarely ruled directly on the standing requirement in the context of patent appeals from the USPTO,¹⁸ though it frequently ruled on district court standing issues.¹⁹ The Federal Circuit recently held, as a matter of first instance, that a party appealing from an administrative proceeding must demonstrate separate Article III standing on appeal.²⁰ In contrast, the Federal Circuit shortly thereafter followed the Supreme Court’s suggestion that the nonmoving party need not prove standing on appeal.²¹

That suggestion came in ASARCO Inc. v. Kadish,²² where the Supreme Court held that, even though the plaintiffs-respondents lacked independent Article III standing (which is not required in a state court action) and thus could not have filed an action in federal court, the Court had jurisdiction over the appeal, as the petitioners had suffered “a specific injury stemming from the [adverse] state-court decree.”²³ Importantly, the Court did not question the plaintiffs-respondents’ participation in the appeal; rather, it held that “the parties remain adverse” because the plaintiffs-respondents were defending the state court’s judgment and that the appeal would resolve a “genuine case or controversy.”²⁴

No court has definitively held that Article III standing is required for appellees where appellants have standing. Rather, most courts suggest that if the party invoking the court’s jurisdiction establishes Article III standing, the inquiry is resolved.²⁵ Some opinions, however, seem to suggest that all parties to an appeal might need to possess independent Article III standing—despite the Supreme Court holding that the appellee is almost invariably in the best position to provide “that concrete adverseness which sharpens the presentation of issues.”²⁶

For instance, in Camreta v. Greene,²⁷ the Supreme Court did find that an opposing party must have an “ongoing interest in the dispute,” so that the case features “that concrete adverseness which sharpens the presentation of issues.”²⁸ Some later court rulings have misconstrued this as the court requiring all parties to an appeal to demonstrate standing. But that case described not constitutional Article III standing, but rather prudential standing—governed by a court’s discretion and inherent ability to control its own docket—which can be relaxed by statute.²⁹

Notwithstanding the above, standing determinations are quite fact-dependent, so much so that, in the Supreme Court’s view, “[g]eneralizations about standing to sue are largely worthless as such.”³⁰

Consumer Watchdog

The Federal Circuit first confronted the appellate standing issue in Consumer Watchdog v. Wisconsin Alumni Research Foundation.³¹ The patent challenge focused on whether stem cells were patent-eligible subject matter; standing was an afterthought.

Consumer Watchdog, “a nonprofit organization dedicated to providing an effective voice for taxpayers and consumers,”³² sought to challenge patents that were, in its words, used to “loot taxpayer funds and force research overseas.”³³ The Wisconsin Alumni Research Foundation (WARF) patents covered primate embryonic stem cells. Consumer Watchdog requested an inter partes reexamination,³⁴ and when its challenge failed, it appealed.

As the party “seeking to invoke federal jurisdiction,” Consumer Watchdog bore the burden of establishing Article III standing, including its injury in fact.³⁵ The Federal Circuit held it failed to do so because Consumer Watchdog did “not allege[] that it is engaged in any activity involving human embryonic stem cells that could form the basis for an infringement claim.”³⁶

Consumer Watchdog conceded no connection to the patent at issue or the claimed subject matter other than alleging that WARF’s “broad and aggressive assertion of [its] patent has put a severe burden on taxpayer-funded research . . . where [Consumer Watchdog] is located.”³⁷ Consumer Watchdog acknowledged that its patent challenge was based on a concern the patent “allowed WARF to completely preempt all uses of human embryonic stem cells, particularly those for scientific and medical research.”³⁸ But the Federal Circuit rejected Consumer Watchdog’s contention because the PTAB’s decision in WARF’s favor “did not invade any legal right conferred upon Consumer Watchdog,” which “was not denied anything to which it was entitled.”³⁹

Thus, alone, “[a] statutory grant of a procedural right, e.g., right to appeal, does not eliminate the requirements of Article III.”⁴⁰ For example, “the statutory grant of a procedural right does not eliminate the requirement that [a party] have a particularized, concrete stake in the outcome of the [administrative proceeding].”⁴¹ Even so, while a patent challenger with the statutory right to appeal a PTAB decision must assert an injury in fact to establish standing, the statutory right can relax the Article III requirements that the injury be imminent and likely to be redressed by a favorable decision (and it can eliminate the prudential standing requirement).⁴²

Phigenix

Thereafter in Phigenix, Inc. v. ImmunoGen, Inc.,⁴³ the Federal Circuit for the first time addressed the full issue of standing on appeal from an AIA action. They adopted the appellant’s legal theory for analyzing standing but found that the evidence failed to prove an injury in fact. While Phigenix was a “loss” for the appellant in this specific case, it was a win for those arguing for a broader basis of standing beyond the “threat of infringement” analysis applied in declaratory judgment actions.

Phigenix, a small research company, sought to license its patent to Genentech, which marketed the FDA-approved drug Kadcyla^®. Phigenix contended that the use and sale of Kadcyla infringed Phigenix’s patent. Genentech declined, noting it had taken a “worldwide exclusive license” to ImmunoGen’s ’856 patent for the use and sale of Kadcyla. In Phigenix’s view, the existence of ImmunoGen’s ’856 patent was causing financial harm to Phigenix by blocking its ability to otherwise license.

Phigenix filed an IPR petition seeking to cancel the claims of the ’856 patent. The PTAB instituted review but ultimately ruled against Phigenix. On appeal, the question of Phigenix’s standing was raised in a motion to dismiss filed by ImmunoGen as appellee. ImmunoGen sought to dismiss the appeal prior to briefing. After briefing on the motion to dismiss was completed, the court declined ImmunoGen’s invitation for an early dismissal and ordered the parties to proceed with briefing on the merits.

The court faced several novel issues that distinguished this case from Consumer Watchdog. First, the court observed that “[i]n the nearly thirty-five years since the court’s inception, [it has] not established the legal standard for demonstrating standing in an appeal from a final agency action.”⁴⁴ The court explained that “[t]his standard must identify the burden of production; the evidence an appellant must produce to meet that burden; and when an appellant must produce that evidence.”⁴⁵

The court largely followed the D.C. Circuit’s approach and held that “an appellant’s burden of production is ‘the same as that of a plaintiff moving for summary judgment in the district court.’”⁴⁶ The court also accepted that this evidence may come from record evidence or may be supplemented on appeal. Finally, “if there is no record evidence to support standing, the appellant must produce such evidence at the appellate level at the earliest possible opportunity.”⁴⁷

Phigenix had presented, by way of an expert declaration, evidence that “[t]he existence of ImmunoGen’s ’856 patent has . . . encumber[ed] Phigenix’s licensing efforts.”⁴⁸ Phigenix also provided “a letter highlighting concerns over the ’856 patent’s validity that its attorney sent to ImmunoGen,” which it alleged “‘underscores the actual, concrete controversy’ between the parties.”⁴⁹ The submitted evidence tried to link Phigenix’s injury—i.e., the inability to license its own patent to Genentech—to the existence of ImmunoGen’s ’856 patent.⁵⁰

In the court’s view, however, Phigenix’s evidence—“[t]he conclusory statements in [an expert’s] Declaration and the letter as to the hypothetical licensing injury”—did not satisfy the requirements of Federal Rule of Civil Procedure 56(c)(4).⁵¹

But the court did not reject Phigenix’s legal theory. The court allowed that “if Phigenix had licensed the ’534 patent to the same parties to which ImmunoGen had licensed the ’856 patent, the invalidation of the ’856 patent might have increased Phigenix’s revenues.”⁵² Decreased revenue is a classic financial harm that can satisfy the injury in fact requirement of Article III.⁵³

Phigenix provides guidance on what type of evidence can be offered to establish standing and when that evidence can be offered. The court also adopted a test for standing that is broader than what is accepted for establishing declaratory judgment jurisdiction, acknowledging that the ’856 patent could have decreased revenue to Phigenix. Thus, the downfall of Phigenix’s appeal was not legal, but rather evidentiary, and it highlights the importance of thinking about the standing issue from the very start of the post-grant proceeding.

PPG Industries

PPG Industries, Inc. v. Valspar Sourcing, Inc.,⁵⁴ while nonprecedential, provides additional insight into what certain judges believe is sufficient to establish standing on appeal from the PTAB. Here, PPG filed inter partes reexaminations on Valspar’s patents when there was no pending district court litigation. When concluded, the PTAB ruled in favor of the patent owner, Valspar.

On appeal, Valspar argued appellant PPG lacked standing. The court requested additional briefing, in which Valspar identified a covenant not to sue it had unilaterally granted to PPG.⁵⁵ In view of the covenant, the court received additional briefing on whether the appeal was moot.

In a short, nonprecedential opinion, the court held that PPG established standing to sue at the time the appeal was filed but the appeal was later rendered moot by the covenant. The opinion’s analysis is not detailed but does identify several pieces of evidence guiding the court, including that (1) PPG had already launched a commercial can-interior coating for the beverage can industry, and (2) PPG had received at least one inquiry from a customer suggesting that Valspar intended to pursue infringement litigation against PPG related to its can-interior coating.⁵⁶

The court concluded, “Unlike Consumer Watchdog, PPG is and was ‘engaged in . . . activity involving [the patented subject matter] that could form the basis for an infringement claim,’ and has ‘other connection[s] to the [patents] or the claimed subject matter,’ sufficient to ‘have a particularized, concrete stake in the outcome of the reexamination.’”⁵⁷ In the court’s view, “[t]his stake is enhanced by the ‘estoppel provisions contained within the inter partes reexamination statute.’”⁵⁸

The court appears to have used an analysis similar to determining standing in the declaratory judgment actions. The court noted that PPG had begun making or selling a can-interior coating, which was presumably a product that PPG believed Valspar would say is infringing.

RPX v. Chanbond

A more recent Federal Circuit action on appellant standing is a nonprecedential order in RPX Corp. v. Chanbond, LLC.⁵⁹ There, the court dismissed an appeal for lack of standing prior to briefing on the merits.

RPX’s “core business is in acquiring patent rights on the open market and in litigation to achieve peaceful resolution of patent disputes through rationally negotiated transactions.”⁶⁰ After risk management competitors did so, RPX also started challenging patents through IPR proceedings. One such patent was Chanbond’s patent directed to the distribution of digital signals onto, and off of, a wideband signal distribution system. While the PTAB instituted an IPR proceeding against the patent, the PTAB ultimately held that the patent claims were not proven unpatentable; RPX sought to challenge the decision on appeal to the Federal Circuit.

In its short nonprecedential order signed by the clerk, the court rejected RPX’s arguments for standing on appeal. First, the order dispatched with RPX’s argument that the PTAB’s decision injures RPX’s “statutory right” to cancel claims. That “statutory right to appeal” argument was decided in Consumer Watchdog, where the court stated that “[t]he statute did not guarantee a particular outcome favorable to the requester.”⁶¹

The court also rejected RPX’s argument that the decision “injures RPX’s standing relative to competitors.”⁶² RPX contended that the PTAB’s adverse decision harms RPX’s standing vis-à-vis its competitors, such as other entities challenging patents. The court dismissed this theory: “RPX has not demonstrated that the Board’s determination increased or aids the competition in the market of the non-defendant IPR petitioners.”⁶³

Finally, the court found as “unconvincing” RPX’s argument that “the Board’s determination injures RPX’s reputation of successfully challenging wrongfully issued patent claims.”⁶⁴

Appellee Standing in PTAB Appeals

Standing also arises in the context of whether a defending appellee must satisfy the standing requirements of Article III. While there is some debate as to whether an appellee must show standing separately—many courts assume if standing is met for one party, it is met for all⁶⁵—it has only been addressed once by the Federal Circuit. There is a subsidiary question of whether, even where constitutional standing is not at issue, the court’s inherent prudential standing, which can be relaxed by statute, might apply.⁶⁶

Personal Audio LLC v. Electronic Frontier Foundation⁶⁷ asked whether an appellee must establish Article III standing to defend a favorable opinion—an issue rarely litigated. It has generally been presumed that an appellee’s standing, if questioned, would arise from the risk of an adverse opinion,⁶⁸ analogous to a defendant’s right to defend.⁶⁹

The court sua sponte asked the parties to brief whether the appellee had standing to participate in the appeal, in view of the court’s holding in Consumer Watchdog “that a PTAB petitioner that does not meet the Article III case-or-controversy requirement does not have standing to invoke judicial power, and thus does not have standing to appeal to this court from a PTAB decision on inter partes reexamination.”⁷⁰

The court cited two standing-to-sue cases⁷¹ and ruled “that standing to appeal is measured for the party ‘seek[ing] entry to the federal courts for the first time in the lawsuit’ . . . . With Article III satisfied as to the appellant, [the appellee] is not constitutionally excluded from appearing in court to defend the PTAB decision in its favor.”⁷² The court quoted Justice Marshall: “Because respondent has not invoked the authority of any federal court, then, federal standing principles are simply inapplicable to him.”⁷³ This lines up with other opinions, which generally give the “defending party” the right to defend itself before the court.⁷⁴

Intervenor Standing

Standing issues most frequently arise with respect to the appellant or the appellee, but do intervenors also need to satisfy the standing requirement? The question isn’t academic—in AIA appeals, the USPTO has the statutory right to intervene. Federal Circuit appeals now routinely include an intervenor, although the USPTO intervenes in fewer cases today than it did when AIA appeals first started appearing at the Federal Circuit.

An intervenor is neither an original plaintiff nor a defendant, but generally is one who has a legal interest in the proceeding. For example, Rule 24 of the Federal Rules of Civil Procedure authorizes an outside entity to intervene in a proceeding and participate “as if [it] were an original party.”⁷⁵ An entity may intervene as a matter of right if that entity “(1) is given an unconditional right to intervene by a federal statute,” or “(2) claims an interest relating to the property or transaction that is the subject of the action” that would be “impair[ed] or impede[d]” without intervention.⁷⁶ Permissive intervention can occur when a statute grants the entity “a conditional right to intervene” or when the person “has a claim or defense that shares with the main action a common question of law or fact.”⁷⁷

Intervening means the intervenor becomes equal to the original parties and can litigate the issues on the merits, even if those parties themselves might have questionable standing claims. For example, an intervenor can undertake all the usual actions, such as asserting claims and defenses, making demands for relief, making discovery requests, and the like.⁷⁸ An intervenor is thus very different than an amicus curiae. An intervenor becomes a true party to the case and has substantial “control of the suit.”⁷⁹

Left unanswered until recently was the question of whether an intervenor needed to satisfy Article III’s standing requirement. The federal appellate courts have reached conflicting decisions on whether an intervenor must satisfy the standing requirement under Article III.⁸⁰

Twice recently, the Supreme Court has expressly “reserve[d] . . . for another day” the issue of intervenor standing.⁸¹ But in 2017, the Supreme Court returned to and resolved this question by holding that an intervenor of right must show Article III standing if it is seeking additional relief. In Town of Chester v. Laroe Estates, Inc.,⁸² the Court followed the narrowest path on which the parties and the United States as amicus curiae could agree. The Court held that “an intervenor of right must have Article III standing in order to pursue relief that is different from that which is sought by a party with standing.”⁸³ In other words, “an intervenor of right must demonstrate Article III standing when it seeks additional relief beyond that which the plaintiff requests”⁸⁴ because “[a]t least one plaintiff must have standing to seek each form of relief requested in the complaint.”⁸⁵

More directly related to PTAB appeals is the Federal Circuit’s Knowles Electronics LLC v. Iancu. There, the patent owner appealed an adverse decision in an inter partes reexamination. The requester declined to participate in the appeal; nonetheless, the USPTO sought to intervene and defend the PTAB’s decision. After briefing and during oral argument, Judge Newman raised the issue of the USPTO’s ability to intervene. After argument, the panel sua sponte asked:

a. When the prevailing party in an inter partes reexamination proceeding before the USPTO’s Patent Trial and Appeal Board (“Board”) declines to appear before this court to defend the decision below, is the USPTO’s Director required to possess Article III standing in order to intervene?

b. If yes, does the Director possess such standing in this appeal?

c. Additionally, if the Director does in fact possess standing; must the Director defend the Board’s decision? Alternatively, what are the ramifications if the Director declines to defend the Board’s decision?⁸⁶

The USPTO relied on Town of Chester and explained that, while “a plaintiff—or person seeking relief from a federal court—must show a ‘personal stake in the outcome,’” “[o]ther parties, such as defendants, appellees, or intervenors who are not seeking affirmative relief, need not have constitutional standing for a case to proceed.”⁸⁷

The appellant did not substantially disagree with the USPTO’s position. It is likely that the court will hold that the USPTO need not independently establish Article III standing if it is merely arguing a position to support the PTAB’s decision. This would be consistent with the Supreme Court’s decision in Town of Chester and would confirm the USPTO’s authority to defend the PTAB’s decisions on appeal, regardless of whether the patent challenger continues through appeal.

While this article was going to press, the Federal Circuit ruled in Knowles that the USPTO does in fact have standing to intervene. The majority dismissed the issue in a long footnote, citing past cases where intervention was allowed in lieu of a settled appellee, and holding affirmatively that the USPTO director had standing—going further than the approach we counsel for here. The panel split, with Judge Newman dissenting on the standing issue alone, arguing that “[w]hen the intervenor does not have an independent interest or injury, and no party remains as appellee on the side favored by the intervenor, the requirements of intervenor status are not met.”⁸⁸

Amicus Standing

In contrast to appellants, appellees, and intervenors, an amicus curiae is not a party. A “friend of the court” is anyone wanting to express his or her views about the case and its potential consequences to others. As one commentator puts it, amici curiae are “nonparties who are nevertheless advocates, who are not bound by rules of standing and justiciability, or even rules of evidence, and who can present the court with new information and arguments.”⁸⁹

Amici thus need not have standing,⁹⁰ as amici are not the party seeking to invoke the court’s jurisdiction.⁹¹ If a potential intervenor is denied intervenor status, courts are likely to permit the party to participate as an amicus.⁹²

Conclusion

The Federal Circuit must consider the broader law addressing standing in appeals from all agency actions and not unduly limit review. The Federal Circuit’s pre-AIA standing jurisprudence has been criticized as too restrictive,⁹³ and the AIA’s statutory purpose of a broad review of patents arguably broadened standing to the constitutional maximum when it authorized judicial review by any party “dissatisfied with the final written decision.”⁹⁴

Luckily, on at least one point, the Federal Circuit appears to be adopting the dominant—and just—view of the other circuits. In Phigenix, the Federal Circuit adopted appellant standing; later, the court found in Personal Audio LLC v. EFF that Article III standing need only be satisfied by the party invoking the court’s appellate jurisdiction. The Federal Circuit recently ruled that the USPTO has standing to intervene in appeals from the PTAB. Procedurally, the Federal Circuit is unlikely to adopt highly formal rules or timing requirements and may accept an ad hoc approach to evidence and briefing throughout appeals. While Phigenix suggests all administrative appeals require establishing appellate standing, it seems unlikely that the Federal Circuit will ever require appellants from administrative actions to prophylactically demonstrate standing, instead waiting until such challenges appear before wading in. But only time will tell.

Endnotes

1. U.S. Const. art. III, § 2, cl. 1.

2. Summers v. Earth Island Inst., 555 U.S. 488, 492–93 (2009).

3. Hollingsworth v. Perry, 133 S. Ct. 2652, 2661 (2013).

4. 258 U.S. 126 (1922).

5. See Joan Steinman, Shining a Light in a Dim Corner: Standing to Appeal and the Right to Defend a Judgment in the Federal Courts, 38 Ga. L. Rev. 813 (2004).

6. Lujan v. Defenders of Wildlife, 504 U.S. 555, 560 (1992).

7. Elk Grove Unified Sch. Dist. v. Newdow, 542 U.S. 1, 12 (2004) (quoting Allen v. Wright, 468 U.S. 737, 751 (1984)).

8. Warth v. Seldin, 422 U.S. 490, 501 (1975).

9. Id. at 500.

10. Linda R.S. v. Richard D., 410 U.S. 614, 617 n.3 (1973); see also Lujan, 504 U.S. at 578; Warth, 422 U.S. at 514 (“Congress may create a statutory right or entitlement the alleged deprivation of which can confer standing to sue even where the plaintiff would have suffered no judicially cognizable injury in the absence of statute.”).

11. Lujan, 504 U.S. at 580 (Kennedy, J., concurring).

12. Consumer Watchdog v. Wisc. Alumni Research Found., 753 F.3d 1258, 1261 (Fed. Cir. 2014).

13. See Ritchie v. Simpson, 170 F.3d 1092, 1095 (Fed. Cir. 1999).

14. See, e.g., Cal. Ass’n of Physically Handicapped, Inc. v. FCC, 778 F.2d 823, 826 n.8 (D.C. Cir. 1985) (“The Commission may choose to allow persons without Article III ‘standing’ to participate in FCC proceedings.”).

15. See Hollingsworth v. Perry, 133 S. Ct. 2652, 2661 (2013).

16. Sierra Club v. EPA, 292 F.3d 895, 899 (D.C. Cir. 2002).

17. E.g., Sierra Club v. EPA, 781 F.3d 299, 306 (6th Cir. 2015); N. Laramie Range Alliance v. FERC, 733 F.3d 1030, 1034 (10th Cir. 2013); Iowa League of Cities v. EPA, 711 F.3d 844, 869–70 (8th Cir. 2013).

18. Earlier cases include Syntex (USA) Inc. v. U.S. Patent & Trademark Office, 882 F.2d 1570 (Fed. Cir. 1989), and Boeing Co. v. Comm’r of Patents & Trademarks, 853 F.2d 878 (Fed. Cir. 1988).

19. See, e.g., Prasco LLC v. Medicis Pharm. Corp., 537 F.3d 1329 (Fed. Cir. 2008).

20. Consumer Watchdog v. Wisc. Alumni Research Found., 753 F.3d 1258, 1261 (Fed. Cir. 2014).

21. Personal Audio, LLC v. Elec. Frontier Found., 867 F.3d 1246 (Fed. Cir. 2017).

22. 490 U.S. 605 (1989).

23. Id. at 617.

24. Id. at 619 (citing Tileston v. Ullman, 318 U.S. 44, 46 (1943)).

25. See, e.g., Bond v. Utreras, 585 F.3d 1061, 1070 (7th Cir. 2009) (holding that standing of an intervenor was irrelevant where the court otherwise had jurisdiction); Legault v. Zambarano, 105 F.3d 24, 26 (1st Cir. 1997) (dismissing challenge to appellee’s standing as a “meaningless quibble”).

26. Los Angeles v. Lyons, 461 U.S. 95, 101 (1983) (citing Baker v. Carr, 369 U.S. 186, 204 (1962)).

27. 131 S. Ct. 2020 (2011).

28. Id. at 2028.

29. Consumer Watchdog v. Wisc. Alumni Research Found., 753 F.3d 1258, 1261 (Fed. Cir. 2014); see also United States v. Windsor, 133 S. Ct. 2675, 2685–86 (2013) (recognizing this requirement’s prudential nature).

30. Ass’n of Data Processing Serv. Orgs., Inc. v. Camp, 397 U.S. 150, 151 (1970).

31. 753 F.3d 1258.

32. About, Consumer Watchdog, http://www.consumerwatchdog.org/about (last visited Apr. 13, 2018).

33. Groups Challenge Stem Cell Patents That Loot Taxpayer Funds and Force Research Overseas, Pub. Pat. Found. (July 18, 2006), http://www.pubpat.org/warfstemcellsfiled.htm.

34. Consumer Watchdog, 753 F.3d at 1260.

35. Id. at 1260–61 (citing Lujan v. Defenders of Wildlife, 504 U.S. 555, 560 (1992)).

36. Id. at 1261.

37. Id. at 1260.

38. Id.

39. Id. at 1262.

40. Id.

41. Id.

42. See id. (“[A] statutory grant of a procedural right may relax the requirements of immediacy and redressability, and eliminate any prudential limitations . . . .” (citing Massachusetts v. EPA, 549 U.S. 497, 517–18 (2007))).

43. 845 F.3d 1168 (Fed. Cir. 2017).

44. Id. at 1172.

45. Id. (footnote omitted).

46. Id. (quoting Sierra Club v. EPA, 292 F.3d 895, 899 (D.C. Cir. 2002)).

47. Id. at 1173.

48. Id. at 1174.

49. Id.

50. Id.

51. Id.

52. Id.

53. See Ass’n of Data Processing Serv. Orgs., Inc. v. Camp, 397 U.S. 150, 150 (1970) (“Certainly he who is ‘likely to be financially’ injured may be a reliable private attorney general to litigate the issues of the public interest in the present case.” (citation omitted)); Lambert v. Hartman, 517 F.3d 433, 438 (6th Cir. 2008) (finding allegation that identity was stolen and that credit rating and financial security suffered was a sufficient injury to confer standing).

54. No. 16-1406, slip op. (Fed. Cir. Feb. 9, 2017) (nonprecedential), http://www.cafc.uscourts.gov/sites/default/files/opinions-orders/16-1406.Opinion.2-7-2017.1.PDF.

55. Id. at 2.

56. Id. at 3.

57. Id. at 4 (alterations in original) (citation omitted) (citing Consumer Watchdog v. Wisc. Alumni Research Found., 753 F.3d 1258, 1261, 1262 (Fed. Cir. 2014)).

58. Id.

59. No. 2017-2346, slip op. (Fed. Cir. Jan. 17, 2018) (nonprecedential).

60. Id. at 2.

61. Consumer Watchdog, 753 F.3d at 1262.

62. RPX, No. 2017-2346, slip op. at 5.

63. Id.

64. Id. at 6.

65. See Rumsfeld v. Forum for Academic & Institutional Rights, Inc., 547 U.S. 47, 52 n.2 (2006) (“[T]he presence of one party with standing is sufficient to satisfy Article III’s case-or-controversy requirement.”); Ry. Labor Execs.’ Ass’n v. United States, 987 F.2d 806, 810 (D.C. Cir. 1993) (“[I]f one party has standing in an action, a court need not reach the issue of standing of other parties when it makes no difference to the merits of the case.”).

66. Consumer Watchdog, 753 F.3d at 1261; see also United States v. Windsor, 133 S. Ct. 2675, 2685–86 (2013) (recognizing this requirement’s prudential nature).

67. 867 F.3d 1246 (Fed. Cir. 2017).

68. Steinman, supra note 5, at 813.

69. Id. at 852 (“While a silent appellee cannot lose a case by ‘default’ as a defendant in the trial court can under Rule 55 of the Federal Rules of Civil Procedure, he would be disadvantaged if barred from arguing to the court of appeals a version of the facts and the law that differs from what the appellant is arguing.”).

70. Personal Audio, 867 F.3d at 1249.

71. ASARCO Inc. v. Kadish, 490 U.S. 605 (1989); U.S. Dep’t of Labor v. Triplett, 494 U.S. 715 (1990).

72. Personal Audio, 867 F.3d at 1250 (citing ASARCO, 490 U.S. at 618).

73. Triplett, 494 U.S. at 732 (Marshall, J., concurring).

74. Cf. Bos. Edison Co. v. Bos. Redevelopment Auth., 371 N.E.2d 728 (Mass. 1977) (granting the appellee the right to present on appeal any ground that was previously asserted in support of a favorable judgment).

75. 7C Charles Alan Wright et al., Federal Practice and Procedure § 1920 (3d ed. Apr. 2016 update).

76. Fed. R. Civ. P. 24(a).

77. Fed. R. Civ. P. 24(b)(1); see also Fed. R. Civ. P. 24(b)(2).

78. Local No. 93 v. City of Cleveland, 478 U.S. 501, 529–30 (1986) (discussing authority of intervenors to block settlement); Bethune Plaza, Inc. v. Lumpkin, 863 F.2d 525, 531 (7th Cir. 1988) (discussing authority of intervenors to demand separate relief and attorney fees). See generally South Carolina v. North Carolina, 558 U.S. 256, 287–88 (2010) (Roberts, C.J., concurring in the judgment in part and dissenting in part) (“Intervenors do not come alone—they bring along more issues to decide, more discovery requests . . . [and] make[] settling a case more difficult . . . .”).

79. Bethune Plaza, 863 F.2d at 531; see also Rio Grande Pipeline Co. v. FERC, 178 F.3d 533, 539 (D.C. Cir. 1999) (contrasting intervenors with amici).

80. Compare King v. Governor of N.J., 767 F.3d 216, 245–46 (3d Cir. 2014); Perry v. Schwarzenegger, 630 F.3d 898, 905–06 (9th Cir. 2011); City of Herriman v. Bell, 590 F.3d 1176, 1183–84 (10th Cir. 2010); Dillard v. Chilton Cty. Comm’n, 495 F.3d 1324, 1336–37 & n.10 (11th Cir. 2007); United States v. Tennessee, 260 F.3d 587, 595 (6th Cir. 2001); and Ruiz v. Estelle, 161 F.3d 814, 829–30 (5th Cir. 1998), with City of Chicago v. Fed. Emergency Mgmt. Agency, 660 F.3d 980, 984–85 (7th Cir. 2011) (treating Article III standing as an additional requirement for intervenors); United States v. Metro. St. Louis Sewer Dist., 569 F.3d 829, 833–34 & n.2 (8th Cir. 2009) (same); and United States v. Philip Morris USA Inc., 566 F.3d 1095, 1145–46 (D.C. Cir. 2009) (same).

81. See McConnell v. FEC, 540 U.S. 93, 233 (2003) (citing Diamond v. Charles, 476 U.S. 54, 68–69 n.21 (1986)), overruled on other grounds by Citizens United v. FEC, 558 U.S. 310 (2010).

82. 137 S. Ct. 1645 (2017).

83. Id. at 1651.

84. Id.

85. Id.

86. Knowles Elecs. LLC v. Matal, No. 2016-1954, slip op. at 2 (Fed. Cir. June 30, 2017) (nonprecedential order). The third question is beyond the scope of this article but raises an important question about the USPTO’s role as intervenor already addressed by Professor Dmitry Karshtedt. See Dmitry Karshtedt, Acceptance Instead of Denial: Pro-Applicant Positions at the PTO, 23 B.U. J. Sci. & Tech. L. 319 (2017).

87. Supplemental Brief for Intervenor at 4, Knowles, No. 2016-1954 (Fed. Cir. July 31, 2017).

88. Knowles Elecs. LLC v. Iancu, No. 2016-1954 (Fed. Cir. Apr. 6, 2018).

89. Helen A. Anderson, Frenemies of the Court: The Many Faces of Amicus Curiae, 49 U. Richmond L. Rev. 361, 361 (2015).

90. See, e.g., NGV Gaming, Ltd. v. Upstream Point Molate, LLC, 355 F. Supp. 2d 1061, 1063, 1068 (N.D. Cal. 2005).

91. See, e.g., Rio Grande Pipeline Co. v. FERC, 178 F.3d 533 (D.C. Cir. 1999) (collecting cases showing conflicting decisions on whether an intervenor must demonstrate Article III standing).

92. See, e.g., Agric. Retailers Ass’n v. U.S. Dep’t of Labor, 837 F.3d 60 (D.C. Cir. 2016) (denying motion to intervene but granting amicus curiae status); Silver v. Babbitt, 166 F.R.D. 418, 434–35 (D. Ariz. 1994), aff’d, 68 F.3d 480, 481 (9th Cir. 1995) (same).

93. John F. Duffy, Standing to Challenge Patents, Enforcement Risk, and Separation of Powers, 83 Geo. Wash. L. Rev. 628, 643 (2015) (“[E]ven within the Federal Circuit’s own jurisprudence, there’s a glaring inconsistency in how the court measures standing to challenge governmental grants of patent rights versus how it measures standing to challenge other governmental grants to competitors.”).

94. 35 U.S.C. § 319 (appeal from IPR); id. § 329 (appeal of PGR).