Federal Rule of Civil Procedure 24(c) requires that a motion to intervene be accompanied by a proposed pleading setting out the claim or defense for which intervention is sought.1Legal Information Institute. Federal Rule of Civil Procedure 24 – Intervention In practice, that means attaching a draft complaint if you want to assert claims in the case, or a draft answer if you want to defend against claims already in the case. The proposed pleading is what lets the judge see concretely what your participation would look like, rather than guessing from the motion alone.
What the Proposed Pleading Must Contain
The rule’s text is short, but the drafting work it demands is not. A proposed pleading has to do several things at once.
It identifies your interest in the dispute with specificity. Not “an interest” in general terms, but the particular legal stake you hold: a contractual right, a property interest, a regulatory position, a third-party beneficiary status under a specific agreement. If a lawsuit involves a contract that affects you, cite the provisions. If a government enforcement action threatens your business operations, identify which operations and how.
It explains how the outcome of the case would affect you if you are left out. This is the piece that connects your interest to the lawsuit actually in front of the judge.
It sets out numbered factual allegations supporting your legal theory, in the same form as any complaint or answer. Vague assertions do not carry a motion to intervene.
And it addresses why the existing parties are not adequately representing your interests. For intervention as of right, that element is required. Even for permissive intervention, showing that you bring a distinct position makes the motion stronger. Reviewing the existing docket before drafting is worth the time: knowing what claims have been pleaded, what discovery has happened, and what arguments the parties have taken lets you pinpoint where your position diverges from theirs.
If you are seeking relief beyond what the plaintiff already seeks, the pleading needs to lay out facts establishing your own standing. The Supreme Court held in Town of Chester v. Laroe Estates, Inc. that “for all relief sought, there must be a litigant with standing,” and that an intervenor of right must demonstrate standing when pursuing additional relief such as a separate money judgment.2Justia Law. Town of Chester v. Laroe Estates Inc, 581 US (2017) If instead you want exactly what an existing party is already pursuing, say so, because the plaintiff’s standing then supports the court’s jurisdiction over your participation.
Complaint or Answer
The form of the proposed pleading tracks the role you intend to play. If you plan to assert claims, you draft a proposed complaint in intervention. If you plan to defend against the claims already asserted, you draft a proposed answer in intervention. The caption should label the document accordingly so the court sees at a glance what will be filed if the motion is granted.
This choice has downstream effects. An answer in intervention responds to the existing complaint paragraph by paragraph and raises affirmative defenses; it does not initiate new claims. A complaint in intervention adds claims to the case and brings with it the pleading standards and procedural posture that come with any new complaint. Picking the wrong form, or mixing the two, invites the court to question whether you understand the role you are asking to take on.
What Happens If You Leave the Pleading Out
Federal circuits are split on whether the omission is fatal. A majority — the First, Fourth, Fifth, Sixth, Eighth, Ninth, Tenth, Eleventh, and D.C. Circuits — treat the requirement flexibly. A judge in those courts can excuse a missing pleading as long as the existing parties had adequate notice of the intervenor’s claims and were not unfairly prejudiced. The Second and Seventh Circuits take a stricter view and treat Rule 24(c) as an unambiguous mandate. In those jurisdictions, filing without the pleading can get the motion denied outright regardless of its merits.
The safe course is to always attach the proposed pleading. Even in a lenient circuit, relying on judicial grace to forgive the lapse offers no upside, and drafting the pleading forces you to think through your legal theory before you file. That tends to produce a stronger motion.
Filing the Motion and the Pleading Together
The proposed pleading is a standalone document attached to the motion, typically titled “Proposed Complaint in Intervention” or “Proposed Answer in Intervention.” Many district courts publish templates on their websites that can serve as a starting point for formatting.
The motion itself identifies the legal basis for intervention, states whether you are seeking intervention as of right or permissive intervention, and directs the court to the attached pleading. It needs a signature block and a certificate of service confirming that all existing parties received copies. Paragraphs in the proposed pleading should be numbered, and the whole package should comply with the local court’s rules on margins, font, and page limits. Those rules vary by district, so check before filing.
Filing generally happens through the federal judiciary’s Case Management/Electronic Case Files (CM/ECF) system, which accepts pleadings, motions, and other documents online.3United States Courts. Electronic Filing (CM/ECF) An active CM/ECF account with the specific district court is required. Paper filing at the clerk’s office remains available for those without electronic access, with an original plus copies for the judge and all parties.
Whether a filing fee applies depends on what the intervention is doing. The base statutory fee for filing a civil action in federal district court is $350, with an additional $55 administrative fee, for a combined total of $405.4Office of the Law Revision Counsel. 28 USC Chapter 123 – Fees and Costs Courts may require this fee when the intervenor is effectively initiating new claims. The District Court Miscellaneous Fee Schedule does not list a separate fee specifically for motions to intervene.5United States Courts. District Court Miscellaneous Fee Schedule Intervening as a defendant to file an answer, rather than to assert new affirmative claims, may not trigger the full civil filing fee. The clerk’s office in the specific district can confirm what applies.
After filing, you serve copies on every existing party. CM/ECF handles service automatically for parties registered for electronic notice; anyone unregistered needs manual service. Existing parties then have a period set by local rules — commonly around 14 days — to oppose. The judge may schedule oral argument or decide on the papers.
Rule 11 Applies to the Pleading You Attach
The proposed pleading is a filing like any other, and Rule 11 certification runs with it. By signing, you or your attorney represent that the filing is not made for an improper purpose, that the legal contentions are warranted by existing law or a nonfrivolous argument to change it, and that the factual allegations have evidentiary support or are likely to after further investigation.6United States District Court Northern District of Illinois. Federal Rule of Civil Procedure 11 – Signing of Pleadings, Motions, and Other Papers
A frivolous intervention motion or a proposed pleading with fabricated allegations can draw sanctions, including payment of the opposing party’s attorney’s fees. Rule 11 does include a 21-day safe harbor: a sanctions motion cannot be filed with the court until 21 days after it is served on the offending party, giving that party time to withdraw or correct the filing.6United States District Court Northern District of Illinois. Federal Rule of Civil Procedure 11 – Signing of Pleadings, Motions, and Other Papers That is a safety net, not a drafting strategy. A proposed pleading that reads as leverage rather than protection of a genuine interest costs credibility with the court even when it avoids formal sanctions.
What the Pleading Does If the Motion Is Granted
If the court grants intervention, the proposed pleading is typically deemed filed as of that date, and the intervenor becomes a full party. The intervenor can then participate in discovery, file motions, and present evidence at trial. Courts retain authority to impose conditions on participation to keep the proceedings efficient, particularly when intervention comes late.1Legal Information Institute. Federal Rule of Civil Procedure 24 – Intervention A court might limit the intervenor to specific issues or decline to reopen discovery that has already closed. The pleading you attached defines the scope of what you will be litigating from that point forward, so it is worth drafting as if it were the operative pleading from the start, because once intervention is granted, that is exactly what it becomes.