Motion to Strike: When Pleadings Cross the Line Under FRCP 12(f)

A motion to strike asks the court to remove material from a pleading on the ground that it is redundant, immaterial, impertinent, or scandalous. Authorized in federal court by Federal Rule of Civil Procedure 12(f), the motion targets specific allegations or defenses rather than the pleading as a whole. Courts grant motions to strike sparingly because pleadings are intended to give notice, not to be tested for tightness, and the rule disfavors striking content that may have any bearing on the case.

This piece sets out the FRCP 12(f) standard, the timing rules, the difference between motions to strike pleadings and motions to strike evidence, the strategic uses of striking affirmative defenses, and the limited situations where a motion to strike actually succeeds. Read it beside the 12(b)(6) guide and the affirmative defenses overview.

FRCP 12(f) Standard

Rule 12(f) authorizes the court to strike from a pleading "an insufficient defense or any redundant, immaterial, impertinent, or scandalous matter." The motion may be made on the court's own initiative or on motion by a party. A party must file the motion before responding to the pleading or, if no response is allowed, within 21 days after being served with the pleading.

The four grounds:

• Insufficient defense: an affirmative defense that fails as a matter of law (legally invalid or unsupported by any allegation).
• Redundant: needless repetition of allegations.
• Immaterial: matter that has no possible bearing on the case.
• Impertinent: matter not pertinent to the issues.
• Scandalous: matter that unnecessarily reflects on character or conduct.

Why Most Motions to Strike Fail

Federal courts apply Rule 12(f) reluctantly because pleadings serve a notice function and trial courts prefer to develop the record rather than prune the pleadings. The motion typically succeeds only when the moving party can show that the challenged matter is both improper and prejudicial. Mere irrelevance or stylistic excess is not enough; courts often state that the moving party must show "no possibility" that the challenged matter has any bearing on the controversy.

Common Targets

Target	Likelihood of grant	Notes
Boilerplate affirmative defenses	Moderate	One of the few common successes; defenses with no factual basis
Punitive damages allegations in non-supporting cases	Moderate to high	When state law forecloses punitives for the claim type
Allegations involving prior bad acts of an attorney or party	Moderate	Particularly when irrelevant to claims
Settlement-related references	Often granted	Federal Rule of Evidence 408 makes them inadmissible
Class allegations in non-class cases	Rare	Usually addressed by motion to deny class certification instead
Pure invective or character attacks	Moderate	Scandalous matter ground

Striking Affirmative Defenses

The most productive use of Rule 12(f) is to strike affirmative defenses that have no factual support. Many defendants plead a long list of affirmative defenses by reflex; courts will sometimes strike defenses that are nothing more than labels with no underlying facts. The post-Twombly trend in some circuits applies the plausibility standard to affirmative defenses, making boilerplate defenses more vulnerable.

Even successful motions to strike affirmative defenses do not end the case; the defendant typically gets leave to amend the answer to add factual support. The strategic value is forcing the defendant to commit to specific theories early.

Timing Under California and Federal Rules

A notice of motion to strike must be given within the time allowed to plead, and if a demurrer is interposed, concurrently therewith. Federal Rule 12(f) is similar: the motion must be filed before responding to the pleading or, if no response is allowed, within 21 days after being served. Late motions are typically denied as untimely, although some courts extend the deadline for good cause.

Object or Move to Strike?

The procedural choice between objecting and moving to strike depends on the context:

• Pleading defects: motion to strike under Rule 12(f) is the appropriate tool.
• Improper trial testimony or exhibits: contemporaneous objection is the proper response, not a motion to strike a pleading.
• Inadmissible declarations on summary judgment: courts now require parties to assert evidentiary objections in their oppositions; motions to strike are no longer the proper procedure in most circuits.

Litigators should know that motions to strike on summary judgment are no longer proper in many circuits; the proper procedure is to assert objections in the opposition memorandum and let the court rule on admissibility as part of its summary judgment analysis.

Connecticut and Other State Variants

The purpose of a motion to strike in Connecticut is to contest the legal sufficiency of the allegations of any complaint to state a claim upon which relief can be granted. In Connecticut practice, the motion to strike serves the same function as a federal Rule 12(b)(6) motion: testing legal sufficiency of the entire pleading or specific counts. This is fundamentally different from federal Rule 12(f), which targets specific objectionable matter, not the legal sufficiency of the entire pleading.

Sanctions and Cost-Shifting

Frivolous motions to strike, particularly those targeting routine pleading content, can draw sanctions under Rule 11 or 28 U.S.C. Section 1927. Rule 12(f) motions are routinely viewed by judges as excessive litigation; selecting targets carefully matters.

Filing Strategy

The motion typically includes:

• The motion identifying the specific allegations or defenses to strike with paragraph numbers.
• A memorandum applying the Rule 12(f) standard.
• Supporting authority showing why each challenged item meets one of the four grounds.
• A proposed order striking the specified content and granting leave to amend if appropriate.

Pinpoint references are essential. Generic motions to strike "the entire complaint" are denied as overbroad; courts want a surgical motion that identifies specific paragraphs.

When You Need an Attorney

Motions to strike are technical and disfavored, but they remain valuable tools in narrow circumstances. Legal Tank's attorney-drafted motion to strike service handles the motion, supporting memorandum, and proposed order. The motion to strike template comes free for self-filers. For broader pleading strategy, see the 12(b)(6) overview.

Frequently Asked Questions

Is it better to object or motion to strike?

It depends on the procedural posture. Litigators should know that motions to strike on summary judgment are no longer proper in many circuits; the proper procedure is to respond to the evidence with objections in the opposition memorandum. For pleading defects (immaterial, impertinent, or scandalous matter, or insufficient affirmative defenses), a Rule 12(f) motion to strike is the appropriate tool. For trial testimony or exhibits, contemporaneous objections are correct. The choice depends on what is being challenged and at what stage.

When must a motion to strike be filed in California?

A notice of motion to strike must be given within the time allowed to plead, and if a demurrer is interposed, concurrently therewith. California Code of Civil Procedure Section 435 sets the timing. The motion must specify the parts of the pleading being challenged with particularity. Late motions can be denied for untimeliness unless the court grants leave for good cause shown. Federal practice is similar: Rule 12(f) requires filing before responding to the pleading or within 21 days after being served.

What is a motion to strike in Connecticut?

The purpose of a motion to strike in Connecticut is to contest the legal sufficiency of the allegations of any complaint to state a claim upon which relief can be granted. The Connecticut motion to strike functions like a federal Rule 12(b)(6) motion, testing whether the complaint states a viable claim. This differs from federal Rule 12(f), which targets specific redundant, immaterial, impertinent, or scandalous matter rather than testing the entire pleading's legal sufficiency.

How long is a motion to strike?

Under FRCP 12(f), a motion to strike must be filed within 21 days of being served with the pleading that one intends to challenge, or before responding to the pleading if no response is allowed. The deadline is mirrored in many state rules. The motion itself is typically 5 to 15 pages, depending on how many specific items are challenged. Concise motions identifying narrow targets succeed more often than sprawling motions challenging large portions of pleadings.