Intervening in a Federal Case or Opposing Intervention: A Practical Guide

Summary. This guide takes a nonparty, and the parties who would rather keep it out, through a federal motion to intervene from the first docket alert to the appeal. It begins with the decisions to make before filing: whether intervention is needed at all, what alternatives exist, what it costs to become a party, and which form of intervention fits the goal. Nine numbered steps for the movant cover fixing the timeliness clock, choosing the scope of intervention, confirming standing and jurisdiction, building the inadequate-representation record, conferring with the parties, drafting the motion and the proposed pleading Rule 24(c) requires, offering conditions, arguing the motion, and acting on the ruling. Six steps for the opposing party cover each line of attack and the fallback of conditioned or limited participation. Separate sections address the recurring nonparty intervenors: competitors and trade associations, insurers, federal and state governments, and the press and public seeking to unseal records. A timeline and cost table, a worked example involving a solar trade association and a proposed consent judgment, common mistakes, an FAQ, and takeaways close the guide.

At 4:40 on a Thursday afternoon, the executive director of the Copperline Solar Installers Association gets a forwarded docket alert. A utility, Mesa Grande Power Co., sued the state's public utilities commissioners in federal court eight months ago, claiming that the state's net-metering statute is preempted by federal energy law. The association followed the case loosely; the commissioners were defending the statute, and the association's members assumed that was enough. The alert says something new. The utility and the commissioners have filed a joint motion asking the court to enter a consent judgment declaring two sections of the statute unenforceable, and the court has set a hearing in 21 days. If the judgment is entered, the association's 140 member companies lose the compensation formula their customers' contracts depend on, and nobody in the courtroom will be arguing against it.

The association can ask to intervene. Whether it gets in depends on things it can still control (how fast it moves, how it frames its interest, what it asks for, and what it files with the motion) and on things it cannot (what the commissioners said in their briefs over the last eight months, and how its circuit reads two recent Supreme Court decisions). This guide walks through both, for the movant and for the parties who will oppose it.

The short answer

• Intervention of right has four elements: a timely motion, a significantly protectable interest in the subject of the action, a risk that the case will practically impair that interest, and inadequate representation by the existing parties. Fed. R. Civ. P. 24(a)(2). The last element needs only a showing that representation "may be" inadequate, and the burden is "minimal." Trbovich v. United Mine Workers, 404 U.S. 528 (1972).
• Permissive intervention needs only a common question of law or fact, but it is discretionary, and the court must weigh delay and prejudice to the original parties. Rule 24(b)(1)(B), (b)(3).
• Timeliness runs from when you knew your interest was unprotected, not from when the case was filed. A motion filed within days of a party's change of position can be timely even years into a case. Cameron v. EMW Women's Surgical Center, P.S.C., 595 U.S. 267 (2022).
• Do not count on a presumption that the government represents you. Berger v. North Carolina State Conference of the NAACP, 597 U.S. 179 (2022) rejected a presumption of adequacy for authorized state agents and stressed the minimal burden; many circuits still apply a "same ultimate objective" presumption, so build an evidentiary record of divergence.
• Seek different relief, bring your own standing. Town of Chester v. Laroe Estates, Inc., 581 U.S. 433 (2017). The D.C. Circuit requires standing of intervenors generally.
• Attach the pleading. Rule 24(c) requires the motion to "be accompanied by a pleading that sets out the claim or defense for which intervention is sought."
• Limited-purpose intervention is the path for the press and the public seeking to unseal records or modify protective orders, and most circuits do not require an independent jurisdictional basis for it.
• Opponents usually win on timeliness or adequacy, and often do better by proposing conditions than by opposing outright.

Before you start: decisions to make

Do you actually need to become a party?

Intervention is not free. An intervenor becomes a party: it is bound by the judgment, it can be served with discovery under Fed. R. Civ. P. 26 and the rules that follow, it is subject to Fed. R. Civ. P. 11, and in fee-shifting cases it may face (or claim) fees. It must comply with scheduling orders it did not negotiate. Before filing, compare intervention with the alternatives.

Class members who object to a settlement may appeal without intervening. Devlin v. Scardelletti, 536 U.S. 1 (2002). Nonparties who are not class members generally must intervene to appeal. Marino v. Ortiz, 484 U.S. 301 (1988). And nonparties are not bound by a judgment merely because they knew about the case and could have intervened. Martin v. Wilks, 490 U.S. 755 (1989). That last point cuts both ways: staying out preserves your right to relitigate, but it does not stop a judgment from changing facts on the ground.

Which kind of intervention fits?

• Intervention of right under a statute (Rule 24(a)(1)). Available only when a federal statute gives an unconditional right. The main examples are the United States or a state when the constitutionality of its statute is challenged, 28 U.S.C. § 2403, the EEOC and aggrieved persons in some Title VII cases, 42 U.S.C. § 2000e-5(f)(1), and the United States in qui tam cases under 31 U.S.C. § 3730.
• Intervention of right based on an interest (Rule 24(a)(2)). The default for parties whose property, contracts, permits, or legal rights are at stake.
• Permissive intervention (Rule 24(b)). For movants with a common question but a weaker or more indirect interest, or as a fallback argument in every Rule 24(a) motion. Government officers and agencies may seek it when a party relies on a statute or regulation they administer. Rule 24(b)(2).
• Limited-purpose intervention. A form of permissive intervention used to unseal records, modify a protective order, or (occasionally) participate in a single issue such as a remedy or a fee dispute.

Where and when?

Most intervention happens in the district court. Intervention on appeal is unusual and, outside agency-review proceedings under Fed. R. App. P. 15(d), has no rule of its own; courts of appeals look to the policies behind Rule 24. Cameron is the leading example. Post-judgment intervention for the purpose of appealing is possible if the motion is filed promptly once the need arises and within the time to appeal. United Airlines, Inc. v. McDonald, 432 U.S. 385 (1977).

Who intervenes, and why

For the full map of party-structuring devices around intervention, see Adding Parties to a Federal Lawsuit: Joinder, Intervention, Impleader, and Interpleader.

Part one: the movant's steps

Step 1: Fix the timeliness clock

What to do. Write down, with documents, the date you first knew or should have known that your interest was at stake and the date you learned it was not being protected. Collect the docket entries, press coverage, and correspondence that show both dates. Then calendar every deadline in the case that might make your participation pointless if missed: a fairness hearing, a dispositive-motion ruling, a trial date, the appeal deadline under Fed. R. App. P. 4(a).

Why. Timeliness is the first element and the one most often dispositive. Courts judge it "from all the circumstances," and the ruling is reviewed only for abuse of discretion. NAACP v. New York, 413 U.S. 345 (1973). The factors most courts use come from Stallworth v. Monsanto Co., 558 F.2d 257 (5th Cir. 1977): how long the movant knew of its interest before moving, the prejudice to the existing parties from the delay (not from intervention itself), the prejudice to the movant if denied, and unusual circumstances. The Supreme Court's recent statement in Cameron emphasizes the most important point for movants: the clock starts when the need to intervene becomes apparent. There, Kentucky's attorney general moved two days after the health secretary declined to seek further review, and the motion was timely though the case was years old.

Pitfalls. Movants lose when they knew for months that a party was taking positions contrary to their interests and waited for the outcome. Courts are skeptical of an intervenor who "sat on the sidelines" until a ruling went the wrong way. A movant whose interest was apparent at filing and who watched the case develop should explain concretely why the existing defense seemed adequate until a specific event.

Timing. Move within days of the trigger, not weeks. If you need time to retain counsel, file a short motion promptly and supplement.

Cost. Low at this stage; the cost of delay is the risk.

Step 2: Choose the scope of intervention

What to do. Decide what you need to do in the case: defend the merits, oppose a settlement, address remedy only, appeal, or unseal. Decide which side you are joining (plaintiff-intervenor or defendant-intervenor). Then frame the motion for that scope, with intervention of right as the main request and permissive intervention as the alternative.

Why. Narrower requests are easier to grant. Courts can and do impose conditions on intervenors, including limits to particular issues, coordination with existing parties, and bans on duplicative discovery. In Trbovich itself, intervention was limited to the claims the Secretary of Labor had raised. Offering a narrow scope shows the court that intervention will not derail the case and preempts the prejudice argument.

Pitfalls. Asking for a full role when you need only one issue invites a fight. But do not concede limits you cannot live with; if you may need to appeal, say so.

Step 3: Confirm standing and subject-matter jurisdiction

What to do. Ask three questions. Will you seek relief different from what an existing party seeks? If so, you need Article III standing for that relief. Town of Chester v. Laroe Estates, Inc., 581 U.S. 433 (2017). Is your circuit one that requires standing for all intervenors? The D.C. Circuit does. Fund for Animals, Inc. v. Norton, 322 F.3d 728 (D.C. Cir. 2003). Is the case in federal court solely on diversity, and are you intervening as a plaintiff? If so, 28 U.S.C. § 1367(b) bars supplemental jurisdiction over your claims where they would be inconsistent with § 1332, so you need complete diversity and the amount in controversy on your own.

Why. Standing questions come back later. An intervenor that participates on the coattails of a party may be stranded if the party settles or declines to appeal: an intervenor appealing alone must show its own standing. Diamond v. Charles, 476 U.S. 54 (1986); Hollingsworth v. Perry, 570 U.S. 693 (2013); Virginia House of Delegates v. Bethune-Hill, 587 U.S. 658 (2019). Build the standing record now, in declarations, so it is available if you need it.

Pitfalls. Some circuits use relaxed interest standards that seem easier to meet than standing. The Sixth Circuit, for example, has described a "rather expansive notion" of the interest sufficient for intervention and has said an intervenor need not have the standing necessary to start a suit. Michigan State AFL-CIO v. Miller, 103 F.3d 1240 (6th Cir. 1997). That helps get in the door but does not help on appeal. For standing doctrine generally, see Pleading and Attacking Standing in Federal Court: A Practical Guide and Article III Standing After TransUnion: Concrete Injury, Traceability, and the End of No-Injury Claims.

Step 4: Define and prove the interest and the impairment

What to do. Identify the specific legal interest: a property right, a contract right, a license, a permit, a regulatory approval, a statutory benefit, or a right of access to judicial records. Show how it relates to "the property or transaction that is the subject of the action." Then show, with a declaration, how disposing of the case without you would as a practical matter impair your ability to protect it: through a judgment that changes legal rules governing you, a consent decree affecting your operations, a disposition of property you claim, or the practical effect of a ruling on future proceedings.

Why. The interest must be "significantly protectable." Donaldson v. United States, 400 U.S. 517 (1971). Courts reject interests that are merely economic and indirect, such as a creditor's interest in a party's solvency. They accept interests in property and contracts at the center of the case, and the Supreme Court has recognized interests in the structure of an antitrust remedy that would govern the intervenors' supply. Cascade Natural Gas Corp. v. El Paso Natural Gas Co., 386 U.S. 129 (1967). Employees whose seniority would be changed by a consent decree have a protectable interest. Brennan v. New York City Board of Education, 260 F.3d 123 (2d Cir. 2001). Impairment is practical, not legal: you need not show that you would be formally bound.

Pitfalls. Avoid describing the interest at too high a level of generality ("our members care about clean energy"). Courts want to see the contract, permit, or right, and a witness who can explain what happens to it if the judgment is entered.

Step 5: Build the inadequate-representation record

What to do. Document how the existing party's interests or positions diverge from yours. Gather the briefs in which the party conceded points you would contest, the statements by officials about their policy preferences, the settlement terms, any change in administration, and any legal duty the party owes to others whose interests differ from yours. Ask the party, in writing, whether it will make the arguments you need and whether it will appeal an adverse ruling. Its answer, or its silence, becomes an exhibit.

Why. Trbovich set a minimal burden: representation "may be" inadequate. Courts of appeals then added presumptions of adequacy when the movant and a party share the same "ultimate objective," and a stronger one when a government entity is charged by law with representing the movant's interest. Arakaki v. Cayetano, 324 F.3d 1078 (9th Cir. 2003). Berger held that no presumption applies where a duly authorized state agent seeks to intervene to defend state law, and it reaffirmed the minimal burden while declining to bless the presumptions in other settings. Since Berger, a movant should argue first that no presumption applies, and second that any presumption is rebutted by specific divergence. Divergence shows up in different objectives (a government defends the public interest broadly; you defend your specific contracts), different litigation choices (concessions, failure to present evidence, a reluctance to appeal), and different incentives (an agency that may prefer to settle).

The Ninth Circuit's en banc decision in Wilderness Society v. U.S. Forest Service, 630 F.3d 1173 (9th Cir. 2011) abandoned its former rule barring private parties from intervening of right on the merits of environmental-statute claims against federal agencies, which opened the door to industry and user groups defending agency decisions. The Fifth Circuit allowed timber companies to intervene in a challenge to Forest Service timber sales because the government's broader public mission might not align with their interests. Sierra Club v. Espy, 18 F.3d 1202 (5th Cir. 1994).

Pitfalls. Do not attack the existing party's lawyers personally. Adequacy is about interests and positions, not competence. And do not argue inadequacy based only on a difference in tactics; most courts require more than a disagreement about strategy.

Step 6: Meet and confer

What to do. Contact every party before filing. Tell them what you will ask for, offer conditions, and ask whether they consent, oppose, or take no position. Many local rules require conferral and a statement in the motion. If a party consents conditioned on limits, write the limits into a proposed stipulated order.

Why. Unopposed motions are granted far more often, and the court will ask what the parties think. Conferring also produces a record: a party that refuses to commit to defending your interest has helped prove inadequacy.

Pitfalls. Do not let conferral delay the filing. If a hearing is imminent, file and report that conferral is ongoing.

Step 7: Draft the motion, the proposed pleading, and the declarations

What to do. Prepare four papers.

1. The motion under Fed. R. Civ. P. 7(b), stating the grounds with particularity and the relief sought, including the proposed scope and any conditions.
2. The memorandum, addressing each Rule 24(a)(2) element in order, then permissive intervention in the alternative, then standing and jurisdiction.
3. The proposed pleading required by Rule 24(c): a proposed answer (if joining the defense), a complaint in intervention (if joining the plaintiffs), or, for limited-purpose intervention, a short motion to unseal or to modify the protective order. The pleading must comply with Fed. R. Civ. P. 8 and, for a defendant-intervenor, should respond to the complaint paragraph by paragraph and state affirmative defenses.
4. Declarations from a knowledgeable witness establishing the interest, the impairment, the standing facts, and the date the movant learned its interest was unprotected.

Add a proposed order granting intervention on the stated terms.

Why. Rule 24(c) is short and courts read it differently. Some deny motions that omit the pleading; others excuse the omission when the movant's position is otherwise clear. Do not test which kind of judge you have. A defendant-intervenor's proposed answer is also the place to preserve defenses that the existing defendant has not raised.

Pitfalls. If the constitutionality of a statute is at issue, check whether the parties have served the notice required by Fed. R. Civ. P. 5.1; if not, the court must certify the question to the relevant attorney general, which may affect timing. Check local rules on page limits, proposed orders, and whether the proposed pleading may be filed as an exhibit.

Cost. For a contested motion with a declaration and proposed pleading, budget roughly in the range of a significant dispositive motion; limited-purpose unsealing motions cost much less.

Step 8: Offer conditions and argue the motion

What to do. In the motion and at argument, offer conditions that answer the opposing parties' prejudice arguments: no reopening of completed discovery, adherence to the existing schedule, joint briefing with an aligned party, page limits, a single set of interrogatories, no new claims. Ask the court to rule promptly if a hearing or ruling is imminent, and consider asking for leave to participate provisionally (for example, by filing a brief for the upcoming hearing) while the motion is pending.

Why. Rule 24(b)(3) requires the court to consider delay and prejudice, and many judges consider them under Rule 24(a) timeliness too. Conditions convert a "no" into a "yes, but." Courts have broad discretion to impose them, and an order granting permissive intervention with conditions is not immediately appealable by the intervenor, Stringfellow v. Concerned Neighbors in Action, 480 U.S. 370 (1987), so propose conditions you can live with.

Step 9: Act on the ruling

If granted. You are a party. Calendar your answer or responsive deadline, serve initial disclosures if required, enter appearances, and confirm how you will coordinate with aligned parties. Your positions now bind you.

If denied. An order denying intervention of right is generally treated as final as to the movant and appealable under 28 U.S.C. § 1291. Denial of permissive intervention is reviewed for abuse of discretion and reversed rarely. Calendar the appeal deadline under Fed. R. App. P. 4(a) from entry of the order (30 days in most civil cases, 60 when the United States or its officer or agency is a party). Some circuits review a denial of permissive intervention only in connection with an appeal from the denial of intervention of right.

Alternatives after denial. Seek leave to file as amicus curiae. Renew the motion if circumstances change (for example, if a party stops defending or a settlement emerges). File a separate action where possible. If you are a class member, object to any settlement.

Part two: the opposing party's steps

Step O1: Decide whether to oppose at all

Opposing intervention costs money and can look defensive. An unopposed or conditioned intervention may be cheaper than a contested motion that the court grants anyway. Consider whether the intervenor would bring evidence or arguments that help you, whether its presence would make a settlement harder, whether it would expand discovery, and whether the judge is likely to grant the motion. Plaintiffs facing a well-funded defendant-intervenor often prefer conditions to opposition.

Step O2: Attack timeliness

Build the chronology the movant would rather not tell: when the case was filed, when it was publicized, when the movant's members or officers learned of it, when the positions it now attacks were first taken, and what has happened since (discovery closed, dispositive motions decided, settlement negotiated in reliance on the existing lineup). Emphasize prejudice caused by the delay, not by intervention itself, because that is the relevant prejudice. Stallworth v. Monsanto Co., 558 F.2d 257 (5th Cir. 1977). In NAACP v. New York, the Supreme Court affirmed a denial where the movants had reason to know of the suit and its implications well before moving.

After Cameron, a movant that moves promptly after a genuine change in a party's position has a strong answer. The opponent's response is to show that the change was not genuine (the party's position had been visible for months) or that the movant's interest was always distinct and therefore always required intervention.

Step O3: Attack the interest and impairment

Argue that the interest is economic and contingent, not legal and direct; that it does not relate to the property or transaction at issue; or that the movant can protect it in a separate proceeding. Point out that the judgment will not bind the movant (Martin v. Wilks), while recognizing that most courts consider practical, not legal, impairment. Insurers are the classic example of a contingent interest: an insurer defending under a reservation of rights generally lacks a sufficiently direct interest in the liability case. Travelers Indemnity Co. v. Dingwell, 884 F.2d 629 (1st Cir. 1989).

Step O4: Defend the adequacy of existing representation

Show that the existing party shares the movant's ultimate objective, has defended vigorously, has made the movant's arguments, and has committed to appeal if necessary. Where a government entity defends a law or agency action, argue the presumption of adequacy that your circuit applies, and distinguish Berger: there, state law expressly authorized the legislative leaders to defend state law on the State's behalf, and the Court relied on that authorization. Movants who are private parties with the same goal as a government defendant are differently situated. Expect the movant to cite Trbovich's minimal burden; respond that a minimal burden is not no burden, and that a disagreement about tactics does not make representation inadequate.

Step O5: Attack permissive intervention on delay, prejudice, and jurisdiction

Explain concretely what intervention would add: new claims, new discovery, new experts, a new round of briefing, a delayed trial, a settlement made harder. Argue that the intervenor's views can be presented as amicus. In diversity cases, check § 1367(b): a would-be plaintiff-intervenor who destroys complete diversity cannot be permitted to intervene. Where the movant seeks to litigate claims rather than unseal records, many courts require an independent jurisdictional basis for permissive intervention.

Step O6: Fall back to conditions

If the court is likely to grant the motion, ask for conditions: participation limited to identified issues, no duplicative discovery, joint briefing with the aligned party, compliance with existing deadlines, no new claims, and page limits. Ask the court to state that the conditions are without prejudice to a later motion to modify them, which gives you a lever if the intervenor overreaches.

Recurring intervenors: what each should know

Competitors and trade associations

Competitors and industry groups most often intervene to defend a government action that benefits them: an agency approval, a license, a rule, a statute. Agency cases under the Administrative Procedure Act, 5 U.S.C. § 702 and § 706, are the main venue. The D.C. Circuit, where many agency cases are heard, requires standing of intervenors and has held that a party that benefits from an agency ruling has standing to defend it and may show that the agency's broader mandate makes its representation potentially inadequate. Crossroads Grassroots Policy Strategies v. FEC, 788 F.3d 312 (D.C. Cir. 2015). In petitions for review filed directly in a court of appeals, Rule 15(d) of the appellate rules requires a motion to intervene within 30 days after the petition is filed, with a concise statement of the interest and the grounds.

Competitors also seek intervention in private cases, and courts are less receptive: a competitor's interest in the outcome of a patent or contract dispute between others is usually economic and indirect. The better path is often a separate declaratory judgment action, discussed in Declaratory Judgment Actions: Jurisdiction, Discretion, and the Race to the Courthouse. Manufacturers whose customers are sued for patent infringement sometimes intervene, but they more often defend directly or file their own declaratory judgment action. Where the manufacturer and its customers are sued together, courts may sever and stay the claims against the customers under the "customer-suit exception" while the case against the manufacturer proceeds, as the Federal Circuit directed in In re Nintendo Co., 756 F.3d 1363 (Fed. Cir. 2014). For agency challenges generally, see Challenging Agency Action Under the Administrative Procedure Act.

Insurers

Insurers ask to intervene in suits against their insureds to protect against collusive settlements, to request special interrogatories that will help resolve coverage, or to oppose consent judgments. Most courts deny intervention of right because the insurer's interest is contingent on the coverage dispute, and many deny permissive intervention because the insurer's presence would put coverage before the jury and create a conflict with its own insured. Dingwell is the standard citation. The insurer's usual alternatives are a separate declaratory judgment action on coverage under 28 U.S.C. § 2201, a reservation-of-rights letter, and, where state law allows, a challenge to an unreasonable or collusive settlement in later coverage litigation. For the coverage side of these disputes, see Business Insurance and Coverage Disputes: CGL, E&O, Cyber, and D&O and, for how settlement demands interact with coverage, Policy-Limits Demands and Insurer Bad Faith: How Time-Limited Demands Set Up Excess Verdicts.

An insurer facing competing claims to its policy limits is in a different position: its tool is interpleader, not intervention. See Party Practice Toolkit: Third-Party Complaints, Intervention Motions, and Joinder Analyses for an interpleader complaint skeleton.

Federal and state governments

Governments have the strongest intervention rights. When a party challenges the constitutionality of a federal or state statute in a case to which the relevant government is not a party, the challenger must file a notice of constitutional question and serve it on the Attorney General of the United States or the state attorney general under Rule 5.1(a); the court must certify the question under § 2403; and the government may intervene within 60 days after the notice is filed or the court certifies the challenge, whichever is earlier, unless the court sets a later time. The court may reject the challenge in the meantime but may not enter a final judgment holding the statute unconstitutional before the time to intervene expires. Rule 5.1(c).

Outside § 2403, governments use Rule 24(b)(2), which allows a federal or state officer or agency to intervene when a party's claim or defense is based on a statute or executive order it administers or a regulation issued under one. In qui tam cases, the United States may intervene during the seal period or, after declining, later on a showing of good cause, 31 U.S.C. § 3730(c)(3); the mechanics are covered in False Claims Act Qui Tam Litigation: The Seal, Materiality, Scienter, and Government Intervention.

State officials seeking to defend state law when another official will not have been the subject of both recent Supreme Court decisions. Berger holds that where state law authorizes officials to represent the State's interests, federal courts should respect that choice and not presume that another state official adequately represents them. Cameron holds that a state attorney general who moves promptly after another official abandons the defense may intervene even on appeal. Both decisions emphasize the State's sovereign interest in defending its own laws. Private parties should not assume that the same solicitude extends to them.

The press and the public

Journalists, public-interest groups, and collateral litigants intervene to unseal judicial records and to modify protective orders. The common-law right of access to judicial records is recognized in Nixon v. Warner Communications, Inc., 435 U.S. 589 (1978); discovery materials not filed with the court are treated differently, Seattle Times Co. v. Rhinehart, 467 U.S. 20 (1984). Courts of appeals have held that limited-purpose permissive intervention is the proper procedural vehicle and that the common question requirement is satisfied by the shared question of whether the records should be confidential. Pansy v. Borough of Stroudsburg, 23 F.3d 772 (3d Cir. 1994); Jessup v. Luther, 227 F.3d 993 (7th Cir. 2000). Most circuits do not require an independent jurisdictional basis for that limited purpose. EEOC v. National Children's Center, Inc., 146 F.3d 1042 (D.C. Cir. 1998); Flynt v. Lombardi, 782 F.3d 963 (8th Cir. 2015). Courts have allowed intervention after judgment to challenge confidentiality orders. Public Citizen v. Liggett Group, Inc., 858 F.2d 775 (1st Cir. 1988).

Collateral litigants seeking to use discovery from one case in another receive particular solicitude in the Ninth Circuit, which favors access to avoid duplicative discovery. Foltz v. State Farm Mutual Automobile Insurance Co., 331 F.3d 1122 (9th Cir. 2003); Beckman Industries, Inc. v. International Insurance Co., 966 F.2d 470 (9th Cir. 1992). A nonparty may also seek access to documents produced under a protective order. San Jose Mercury News, Inc. v. U.S. District Court, 187 F.3d 1096 (9th Cir. 1999). Where documents are filed in connection with a dispositive motion, the Second Circuit treats them as judicial documents subject to a strong presumption of access. Lugosch v. Pyramid Co. of Onondaga, 435 F.3d 110 (2d Cir. 2006).

For the sealing standards themselves and how parties negotiate around them, see Negotiating a Protective Order and Filing Under Seal: A Practical Guide, the Confidentiality Toolkit: Protective Orders, Designation Challenges, and Sealing Motions, and the Protective Order and Sealing Checklist: A Practical Checklist.

Class members and objectors

Class members can protect themselves through Rule 23(e) objections, and Fed. R. Civ. P. 23(d)(1)(B)(iii) lets the court give class members an opportunity to intervene. Intervention matters most where the named plaintiffs abandon a position, such as declining to appeal the denial of certification, as in United Airlines v. McDonald. See Class Actions Under Rule 23: Certification, Settlement, and Defense Strategy.

Timeline and cost table

The figures below are rough planning ranges for a single contested motion in a typical federal district court; actual costs vary with the market, the complexity of the record, and whether there is an appeal.

Worked example: the net-metering consent judgment

The facts. Recall the Copperline Solar Installers Association. Its 140 members install residential systems under customer contracts that assume the compensation formula in two sections of the state's net-metering statute. Mesa Grande Power sued the three state utility commissioners eight months ago, alleging that federal law preempts those sections. The commissioners, represented by the state attorney general's office, filed a motion to dismiss that was denied, then an answer. A new governor took office three months ago and appointed two new commissioners. Last Thursday, Mesa Grande and the commissioners filed a joint motion for entry of a consent judgment declaring the two sections preempted. The fairness hearing is in 21 days. The state legislature is not in session. A separate statute authorizes the legislature's presiding officers to defend state statutes in court, but they have not acted.

Step 1: The clock. The association's executive director documents the trigger: the joint motion, filed Thursday. Before that, the commissioners were defending the statute; their briefs argued against preemption. The association's counsel concludes that the trigger for timeliness is the joint motion, under Cameron-style reasoning, and that the motion should be filed within a week.

Step 2: Scope. The association seeks intervention as a defendant, limited to opposing entry of the consent judgment and defending the two sections on the merits if the court declines to enter it. It does not seek to add claims or to reopen discovery, which closed last month.

Step 3: Standing and jurisdiction. The case arises under federal law, so § 1367(b) is irrelevant. The association will seek the same relief as the original defendants sought before the settlement (dismissal and a judgment upholding the statute), but because the commissioners now seek the opposite, the association will in substance seek relief different from that of any remaining party. Counsel therefore builds a standing record under Laroe: declarations from three member companies showing that the consent judgment would cut their revenue under existing customer contracts, which is a concrete injury traceable to the judgment and redressable by its denial. Associational standing requires that members would have standing, that the interests are germane to the association's purpose, and that individual participation is not required, and the declarations address each.

Step 4: Interest and impairment. The interest is legal and specific: members' contracts and business models rely on statutory compensation rights. The impairment is direct: a consent judgment would declare the sections unenforceable against the commissioners who administer them.

Step 5: Inadequate representation. This step is easy now that the commissioners have changed sides. The association's counsel nonetheless documents the change: the earlier briefs defending the statute, the press release announcing the settlement, and a letter asking the attorney general's office whether it will oppose entry of the consent judgment (the answer: the office represents the commissioners and supports the settlement). The association also writes to the legislature's presiding officers, asking whether they will seek to intervene under the state authorization statute; if they do, Berger will help them, and the association can coordinate.

Step 6: Conferral. Mesa Grande opposes. The commissioners take no position. The presiding officers say they are considering their own motion.

Step 7: Papers. Counsel files a motion to intervene as of right and, alternatively, permissively; a memorandum; a proposed answer that responds to the complaint and asserts the defenses the commissioners raised in their motion to dismiss; a proposed opposition to entry of the consent judgment; three member declarations; a declaration from the executive director on the timeline; and a proposed order.

Step 8: Conditions and argument. The motion offers to comply with the existing schedule, take no new discovery except a short deposition of a Mesa Grande witness on the settlement's effects (or none, if the court prefers), and file a single consolidated brief. At the hearing, Mesa Grande argues untimeliness (the association knew of the case for eight months) and lack of interest (the association's members are not regulated parties). The court rejects both: the association had no reason to intervene while the commissioners were defending, it moved within days of their reversal, and the members' contracts are directly affected.

Step 9: The ruling and after. The court grants intervention of right, limited as offered, and continues the fairness hearing by 30 days to allow briefing. Two weeks later, the legislature's presiding officers move to intervene; the court grants that motion too, citing Berger. At the continued hearing, the court declines to enter the consent judgment, observing that parties may settle their own dispute but cannot, by consent, dispose of the valid claims or defenses of a nonconsenting intervenor or impose obligations on it, Local No. 93, International Ass'n of Firefighters v. City of Cleveland, 478 U.S. 501 (1986), and it sets a schedule for summary judgment.

The opponent's view. Mesa Grande's best argument was not timeliness but scope. Had it conceded intervention and asked the court to limit the association to the consent-judgment issue and to bar it from appealing any merits ruling on which the commissioners did not appeal, it might have obtained a narrower order. Its outright opposition produced a full-scope intervenor.

Common mistakes

For movants:

1. Waiting for the result. Watching a case for months and moving after a bad ruling is the most common way to lose on timeliness.
2. Describing an interest instead of proving it. The motion needs a declaration with the contract, permit, or right, not adjectives.
3. Omitting the Rule 24(c) pleading. Some courts deny on that ground alone.
4. Relying on Berger as if it abolished presumptions. It did not; build a divergence record.
5. Forgetting standing for distinct relief or a solo appeal. Laroe and Hollingsworth have ended many intervenors' cases.
6. Asking for too much. Full-scope intervention invites a fight; offer conditions.
7. Ignoring § 1367(b). A plaintiff-intervenor in a diversity case who shares citizenship with a defendant cannot get in.
8. Missing the appeal deadline from the denial order. The clock runs from entry of the order denying intervention, not from the final judgment in the main case.

For opponents:

1. Arguing prejudice from intervention itself. The relevant prejudice is from the delay.
2. Treating every intervenor the same. Limited-purpose unsealing intervenors are judged by different standards.
3. Opposing outright when conditions would do. A court inclined to grant will grant more if no one asks for limits.
4. Overstating the government's representation. After Berger, a bare presumption is weak; show the government's actual vigorous defense.

Frequently asked questions

How late is too late? There is no fixed deadline. Motions filed after judgment have been timely where they were filed promptly after the need arose and within the appeal period (United Airlines v. McDonald, Cameron), and motions filed early in a case have been untimely where the movant had reason to move even earlier. The question is always why you waited.

Do I need a lawyer admitted in that court? Yes, for an organization. Corporations and associations must appear through counsel; individuals may appear pro se, though courts are cautious about permitting individual intervention in complex cases.

Will I have to produce documents? Once you are a party, you are subject to party discovery. Conditions can limit it, but do not assume immunity.

Can I intervene just to appeal? Sometimes. A post-judgment motion to intervene for the purpose of appealing can be timely if filed promptly once it becomes clear that no party will appeal. You will need standing to appeal on your own.

Can a newspaper intervene in a closed case? Yes. Courts have permitted intervention after judgment to challenge confidentiality orders and seek access to sealed records, as in Public Citizen v. Liggett Group and Jessup v. Luther.

Does an order denying intervention end my options? No. You can appeal (for intervention of right), renew the motion if circumstances change, seek amicus status, or bring a separate action. You are also not bound by the judgment under Martin v. Wilks, unless an exception applies.

What if the existing party and I agree on the result but not on the arguments? Courts usually treat a disagreement over arguments or tactics as insufficient to show inadequacy. Show that the difference reflects a divergence in interests (for example, a party whose duties to the public lead it to concede a point that matters only to you).

Takeaways

• Fix and document the timeliness trigger; move within days of it.
• Prove a specific, legally protectable interest with declarations and attach the proposed pleading Rule 24(c) requires.
• Build a record of divergence from the existing party; do not rely on presumptions either way.
• Establish standing if you seek distinct relief or may need to appeal alone.
• Offer conditions; they win motions and limit costs.
• For opponents, timeliness and adequacy are the strongest arguments, and conditions are the best fallback.
• For the press and collateral litigants, limited-purpose permissive intervention is the established path to unsealing.

For the doctrine behind each step, see Adding Parties to a Federal Lawsuit: Joinder, Intervention, Impleader, and Interpleader. For the task list, see Party Joinder and Third-Party Practice Checklist: A Practical Checklist.

This document is general information, not legal advice for any particular situation. Intervention standards vary by circuit and turn on specific facts; consult counsel about your case.

Related Documents

Related Articles

• Adding Parties to a Federal Lawsuit: Joinder, Intervention, Impleader, and Interpleader: the doctrine of intervention in the context of every party-structuring device.
• Protective Orders, Confidentiality Designations, and Sealing: Secrecy and Its Limits in Federal Court: the access standards behind press intervention.
• False Claims Act Qui Tam Litigation: The Seal, Materiality, Scienter, and Government Intervention: the government's statutory intervention right.
• Article III Standing After TransUnion: Concrete Injury, Traceability, and the End of No-Injury Claims: the standing showing an intervenor may need.
• Declaratory Judgment Actions: Jurisdiction, Discretion, and the Race to the Courthouse: the alternative to intervention for competitors and insurers.
• Policy-Limits Demands and Insurer Bad Faith: How Time-Limited Demands Set Up Excess Verdicts: the insurer's exposure when it stays outside the liability case.

Related Guides

• Negotiating a Protective Order and Filing Under Seal: A Practical Guide: sealing practice from the parties' side.
• Pleading and Attacking Standing in Federal Court: A Practical Guide: building the standing record in declarations.
• Challenging a Government Agency Decision: A Practical Guide: where competitor and association intervention most often arises.
• Moving for or Opposing Leave to Amend a Pleading: A Practical Guide: the parallel discretionary-leave standards.

Related Checklists

• Party Joinder and Third-Party Practice Checklist: A Practical Checklist: intervention and joinder tasks in sequence.
• Protective Order and Sealing Checklist: A Practical Checklist: sealing and unsealing tasks.
• Interlocutory Appeal Checklist: A Practical Checklist: appellate options when intervention is denied.

Related Toolkits

• Party Practice Toolkit: Third-Party Complaints, Intervention Motions, and Joinder Analyses: a motion to intervene, proposed pleading, and opposition outline.
• Confidentiality Toolkit: Protective Orders, Designation Challenges, and Sealing Motions: unsealing and protective-order papers.
• Justiciability Toolkit: Standing Allegations, Rule 12(b)(1) Motions, and Mootness Briefing: standing declarations and briefing.