What Is Rehearing En Banc in a DOL 401(k) Rule Challenge?

Rehearing is not a second appeal.

It asks the same court of appeals to reconsider a decision it has already made.

That can happen in two ways:

• the original panel reconsiders
• the court takes the case en banc.

Those routes now live in the same federal rule.

Since December 1, 2024:

Federal Rule of Appellate Procedure 40 governs both panel rehearing and en banc determination.^[1][2]

Older materials that direct readers to standalone Rule 35 for en banc rehearing are outdated on that procedural point.

Panel Rehearing and En Banc Review Solve Different Problems

Current Rule 40 makes the distinction explicit.^[1]

Panel rehearing

The ordinary reconsideration mechanism.

The petition identifies a point of:

• law
• fact

that the panel overlooked or misapprehended.^[1]

Rehearing en banc

An extraordinary procedure.

The full court's intervention is generally reserved for:

• conflict with circuit precedent
• conflict with Supreme Court precedent
• conflict with an authoritative decision of another court of appeals
• a question of exceptional importance.^[1]

The first asks:

Did this panel miss something?

The second asks:

Does the institutional court need to intervene?

En Banc Review Is Not Favored

Rule 40 says so directly.^[1]

That matters because appellate losers routinely believe their case is important.

The rule demands more.

A petition should not merely repeat:

"The panel got the law wrong."

It must explain why full-court review is institutionally warranted.

Examples include:

• two circuit precedents that cannot coexist
• a panel rule inconsistent with Supreme Court authority
• a question affecting a major federal regulatory program.

A DOL retirement rule can involve large national consequences.

That does not make rehearing automatic.

The Rule Number Changed in 2024

This is an easy current-law trap.

Before December 1, 2024:

• Rule 40 primarily governed panel rehearing
• Rule 35 governed en banc hearing and rehearing.

The 2024 amendments consolidated both subjects in Rule 40.^[1][2]

Rule 35 now states:

Transferred to Rule 40.^[2]

That means an article published today should not tell readers:

"File an en banc petition under current Rule 35."

Historical filings can still cite the old numbering accurately.

Current procedure uses Rule 40.

DOL Cases Usually Have a Longer Filing Window

The ordinary federal rehearing period is:

14 days after judgment.^[1]

But Rule 40 contains a different rule for civil cases involving:

• the United States
• a United States agency
• specified federal officers or employees.^[1]

In those cases, the default period is:

45 days.^[1]

A civil challenge naming the Department of Labor or Secretary of Labor therefore will commonly use that longer period unless the court enters a different order.

This is a meaningful difference.

Applying the 14-day default mechanically can produce a false deadline.

The 45-Day Rule Applies to Any Party in the Covered Civil Case

Rule 40 does not give only the government 45 days.^[1]

When the civil case falls within the federal-party categories, the petition may generally be filed by:

any party

within the 45-day period, absent a case-specific order changing the time.^[1]

That matters in DOL litigation because:

• DOL may lose
• industry plaintiffs may lose
• intervenors may lose.

The longer federal-case window can govern whichever party seeks rehearing.

Always verify the docket and local rules.

One Filing Usually Covers Both Requests

A party can seek:

• panel rehearing
• rehearing en banc
• both.^[1]

Unless a local rule provides otherwise, a party requesting both generally files them in:

one document.^[1]

That combined filing still has to satisfy the distinct substantive standards for each request.

A section arguing that the panel misread one factual point does not automatically establish:

exceptional importance

for en banc review.

One document.

Two legal functions.

The Petition Is Deliberately Short

Current Rule 40 generally limits a computer-produced rehearing petition to:

3,900 words.^[1]

A handwritten or typewritten filing ordinarily cannot exceed:

15 pages.^[1]

The purpose is obvious.

Rehearing is not a second merits brief.

The court has already received:

• opening briefs
• response briefs
• reply
• record
• oral argument where held.

The petition must identify the specific reason reconsideration is justified.

Rewriting the entire appeal is usually the wrong strategy.

The Other Side Does Not Automatically Respond

Rule 40 reverses the normal briefing assumption.^[1]

Unless the court requests a response:

no response is permitted.

The rule also says rehearing ordinarily will not be granted without the court first requesting a response.^[1]

That makes a response request procedurally informative.

It does not mean the petition will succeed.

But silence from the opposing party may simply mean:

the rules prohibit a filing at that stage.

It is not evidence that the opposition has conceded the petition.

There Is No Oral Argument on Whether to Grant Rehearing

The federal rehearing rule now in force also says oral argument on the grant question:

is not permitted.^[1]

If rehearing is granted, the court can later:

• decide without further briefing
• request supplemental briefing
• order argument
• enter another appropriate order.^[1]

The petition stage is therefore paper-driven.

A lawyer does not obtain en banc argument merely by asking for en banc review.

The court first decides whether to reopen the case.

Who Votes on En Banc Rehearing?

The consolidated rehearing rule and 28 U.S.C. 46(c) supply the basic structure.^[1][4]

A majority of circuit judges who are:

• in regular active service
• not disqualified

may order rehearing en banc.^[1]

The rule also says:

no vote need be taken unless a judge calls for one.^[1]

That means filing an en banc petition does not guarantee:

• a poll
• a recorded vote
• a written dissent from denial.

The petition can end without the full court ever voting.

"Full Court" Does Not Always Mean Every Judge Associated With the Circuit

Senior judges require special care.

Section 46(c) generally defines the en banc court around judges in:

regular active service.^[4]

A senior circuit judge can participate in specified circumstances, including when that judge was a member of the original panel and elects to participate as permitted by the statute and circuit rules.^[4]

That is more precise than:

"All judges on the circuit rehear the case."

Recusals, vacancies, senior status and statutory eligibility can change the actual en banc composition.

Filing a Petition Does Not Vacate the Panel Opinion

This is one of the most important status distinctions.

A party files for rehearing.

That event does not itself mean:

• panel opinion erased
• judgment reversed
• case now en banc
• DOL rule status automatically changed.

What the timely petition does affect is:

the mandate timeline.^[3]

Rule 41 delays issuance while rehearing remains unresolved.^[3]

The merits result changes only if the court takes further action.

The Panel Can Still Act While En Banc Review Is Requested

Current FRAP 40 expressly preserves the panel's authority after a petition for rehearing en banc is filed.^[1]

The panel can act under the rule's rehearing provisions even while the broader request is pending.

That matters because a panel may:

• amend language
• correct an issue
• modify its disposition.

The filing of a petition seeking full-court review does not instantly transfer control of every question away from the original panel.

What Happens If the Fifth Circuit Grants En Banc Review?

Local rules matter.

Fifth Circuit Rule 41.3 provides that, unless the court expressly says otherwise, granting rehearing en banc:^[5]

• vacates the panel opinion
• vacates the panel judgment
• stays the mandate.

Recent Fifth Circuit orders in 2026 continue to apply that rule expressly.^[13]

This is a much stronger event than:

petition filed.

The progression is:

panel decision → petition → en banc granted → panel opinion and judgment vacated under Fifth Circuit rule → full-court proceeding.

The grant changes the legal status of the panel decision.

A Denied Petition Does Not Rewrite the Panel Opinion

Now take the opposite result.

Rehearing is denied.

The denial generally means:

the court declined to reopen the decision.

It does not necessarily mean every active judge:

• agrees with every sentence
• voted
• endorses every rationale.

Current FRAP 40 expressly allows a petition to be denied without a full-court vote if no judge calls for one.^[1]

So this summary is too strong:

"The full circuit unanimously approved the panel opinion."

A denial order may support no such inference.

The Mandate Is the Next Critical Event

Federal Rule of Appellate Procedure 41 defines the appellate mandate.^[3]

Unless the court directs otherwise, it consists of:

• a certified copy of the judgment
• the opinion, if any
• directions about costs.^[3]

Rule 41 generally schedules issuance:

• seven days after the rehearing period expires
• or seven days after denial of a timely rehearing petition
• or after denial of another qualifying mandate-stay request, whichever is later.^[3]

The court can alter the timing by order.

The mandate becomes effective when issued.^[3]

Judgment and Mandate Are Different Dates

The panel may enter judgment on:

Day 1.

The mandate can issue weeks later.

Those dates should not be collapsed.

The interval exists partly because the rules preserve time for:

• panel rehearing
• en banc review
• mandate-stay requests.^[1][3]

For a DOL rule challenge, a status tracker should record both:

judgment date

and:

mandate date.

The difference can matter to agency implementation.

The 2018 Fiduciary Rule Is the Retirement Example

On March 15, 2018, a divided Fifth Circuit panel decided Chamber of Commerce v. Department of Labor.^[6]

The panel:

• reversed the district court
• vacated DOL's 2016 Fiduciary Rule in toto.^[6]

Chief Judge Carl Stewart dissented.^[6]

That was a major retirement-law ruling.

But the March 15 panel opinion was not the end of the appellate procedural story.

The next question was whether the decision would be reheard before mandate.

DOL Did Not Obtain Rehearing of the Panel Decision

The unusual feature is who tried to keep the rule alive.

California, New York and Oregon were not existing parties to the appeal.

On April 26, 2018, the states moved to:

intervene.^[7]

At the same time, they tendered a petition seeking rehearing en banc.^[8]

The Department of Labor took no position on the states' intervention request.^[7]

That posture exposes an important appellate rule:

strong policy interest does not make someone a party.

The states first needed procedural standing inside the case.

The States Could Not Simply Replace DOL

The states argued that they had significant interests in retirement investors and in preserving the fiduciary rule.^[7][8]

But the case already had:

• industry plaintiffs
• DOL
• the Secretary of Labor.

The states were proposed intervenors.

Their attempt to press en banc review depended on first gaining party status.

The Fifth Circuit denied intervention.

The result shows why this shortcut is unreliable:

"If the federal agency does not seek rehearing, another government can just do it instead."

Not without an adequate procedural basis.

The States Tried Again

After the intervention denial, the states filed a motion for reconsideration on May 16, 2018.^[9]

They again argued for entry into the litigation so they could defend the rule.

On May 22, the Fifth Circuit denied reconsideration.^[10]

The court also denied the states' alternative request to permit filing a petition for full-court rehearing seeking review of the intervention ruling.^[10]

That meant the states did not obtain the en banc path they wanted.

No full-court merits rehearing of the fiduciary-rule decision followed.

The Failed En Banc Effort Did Delay Procedural Completion

The panel opinion arrived March 15.

The mandate did not issue that day.

The intervention and rehearing-related proceedings occupied the weeks that followed.^{[7][8][9][10]}

The final operative appellate step came later.

On:

June 21, 2018

the Fifth Circuit issued its judgment and mandate vacating the 2016 fiduciary-rule package in toto.^[11][12]

DOL later described that date explicitly in the Federal Register.^[11]

That is the date that matters when tracing what the Department did next.

What Did the June 21 Mandate Do?

DOL's 2020 Notice of Court Vacatur explains the regulatory effect.^[11]

The mandate's vacatur reinstated the prior framework, including:

• the 1975 investment-advice fiduciary regulation
• Interpretive Bulletin 96-1
• the pre-2016 structure of affected prohibited transaction exemptions.^[11][12]

DOL later issued technical amendments to make the Code of Federal Regulations conform to the court mandate.^[11]

This sequence is why:

panel opinion date

and:

operative mandate date

should both appear in a retirement-law timeline.

A Rehearing Filing Can Delay the Mandate Without Winning Anything

Suppose DOL loses a panel case.

It timely seeks rehearing.

Rule 41 generally delays the mandate while the petition is unresolved.^[3]

Two very different outcomes remain possible.

Petition denied

The panel result survives.

Mandate then follows according to Rule 41 or a court order.

Rehearing granted

The prior judgment may be displaced and the case reopened under the governing federal and local rules.

The filing itself tells a compliance team:

wait for the next order.

It does not tell the team:

the panel result has been reversed.

Rehearing Can Affect Supreme Court Timing

Circuit rehearing also changes the next appellate clock.

Supreme Court Rule 13 ordinarily gives a party:

90 days

to seek certiorari from a federal court of appeals judgment.^[14]

The key rule is what starts that period.

It runs from:

entry of judgment—not issuance of the mandate.^[14]

But a timely rehearing petition changes the calculation.

The Supreme Court period then runs from:

• denial of rehearing
• or the later judgment if rehearing is granted.^[14]

That is why using the mandate date as the certiorari start date is wrong.

Certiorari and En Banc Rehearing Are Different Choices

A party that loses before a circuit panel can consider:

• panel rehearing
• en banc reconsideration
• Supreme Court certiorari.

They serve different institutions.

Panel reconsideration

Same judges reconsider.

En banc

Circuit reconsiders institutionally.

Certiorari

Supreme Court decides whether to review the circuit judgment.

A party does not automatically have to win or even seek en banc rehearing before petitioning the Supreme Court.

But a timely rehearing filing can alter the certiorari deadline.^[14]

The strategy and deadline questions should be separated.

Worked Example: Analyst Uses the Old Rule Number

Memo dated 2026 says:

"En banc rehearing is governed by FRAP 35."

That is stale.

Current Rule 35 says its contents were:

transferred to The consolidated rehearing rule.^[2]

Historical 2018 briefs properly cited the rules then in force.

A current procedural guide should use current Rule 40.

Worked Example: DOL Case Is Given a 14-Day Deadline

Panel judgment entered against DOL.

Researcher writes:

"Rehearing petition due in 14 days."

Not safely.

The consolidated appellate rehearing rule gives a 45-day default in covered civil cases involving:

• the United States
• a federal agency
• specified federal officers.^[1]

A DOL rule challenge commonly falls inside that federal-party category.

The actual docket still controls.

Worked Example: Petition Filing Is Reported as En Banc Review

Headline says:

"Full Fifth Circuit reopens DOL case."

Underlying event:

a party filed a petition.

That is not enough.

The full court has not necessarily:

• voted
• granted review
• vacated the panel result.

Call it:

petition for full-court review filed.

Reserve:

case reheard en banc

for a grant.

Worked Example: Nonparty Tries to Control the Appeal

State regulator strongly supports a DOL rule.

DOL loses and declines rehearing.

Regulator files that full-court petition despite never becoming a party.

The 2018 states' effort shows the missing step.^[7][8][10]

The proposed intervenor must establish a procedural right to participate.

Policy interest alone does not hand over control of the federal agency's appeal.

Worked Example: Denial Is Called Unanimous Approval

En banc petition denied with a one-line order.

Article says:

"Every active judge approved the panel decision."

The consolidated rehearing rule does not support that inference.^[1]

A vote need not occur unless a judge calls for one.

Even when votes are disclosed, denial means:

rehearing was not granted.

It is not a second merits opinion unless the court writes one.

Worked Example: Mandate Date Is Used for Certiorari

Circuit judgment:

March 1.

Mandate:

April 20.

No rehearing.

Memo counts 90 days from April 20 for Supreme Court review.

Wrong starting premise.

Supreme Court Rule 13 measures from judgment, not mandate.^[14]

If rehearing was timely sought, then the rehearing disposition changes the start date.

The mandate remains a different procedural event.

Post-Panel Status Checklist

Before describing a DOL appellate result as complete, verify:

Panel judgment

What did the three-judge panel decide?

Rehearing deadline

Is the ordinary 14-day period or federal-party 45-day period applicable?

Petition

Was rehearing by the original panel, en banc rehearing or both requested?

Party status

Who filed the request?

Response

Did the court request opposition briefing?

Vote or order

Was rehearing:

• denied
• granted
• unresolved?

Panel action

Did the panel amend its opinion while rehearing was pending?

Local rule

What happens to the panel judgment if en banc review is granted?

Mandate

Has it issued?

Supreme Court clock

Did a timely petition for reconsideration change the certiorari deadline?

Those ten fields give a better status than:

appeal decided.

A Practical Rehearing Matrix

The table is chronological.

The events are not interchangeable.

Fast Answers

What is rehearing by the original panel?

A request for the original appellate panel to reconsider a point of law or fact it overlooked or misapprehended.^[1]

What is rehearing en banc?

An extraordinary procedure asking the circuit to reconsider a panel decision through the court's en banc process.^[1][4]

Is en banc review routine?

No. FRAP 40 says it is not favored.^[1]

Is current en banc procedure still in Rule 35?

No. Effective December 1, 2024, the former Rule 35 material was transferred into The governing rehearing rule.^[1][2]

How long does a party normally have?

Fourteen days after judgment unless another rule, local rule or order applies.^[1]

What about a civil case involving DOL?

The default is generally 45 days because a United States agency is a party.^[1]

Can a party request panel and en banc rehearing together?

Yes. They generally appear in one document unless local rules provide otherwise.^[1]

Does the opposing party automatically file a response?

No. A response ordinarily is not permitted unless the court requests one.^[1]

Is there oral argument on whether rehearing should be granted?

No.^[1]

Does every en banc petition receive a vote?

No. A vote need not occur unless a judge calls for one.^[1]

Does filing an en banc filing vacate the panel opinion?

No.

What happens if the Fifth Circuit grants en banc rehearing?

Under Fifth Circuit Rule 41.3, the panel opinion and judgment ordinarily are vacated and the mandate is stayed.^[5][13]

What does a timely rehearing filing do to the mandate?

It ordinarily delays mandate issuance until the petition is resolved.^[3]

What happened after the Fifth Circuit's March 2018 Fiduciary Rule decision?

California, New York and Oregon sought intervention and attempted to pursue en banc review, but the court denied their effort.^{[7][8][9][10]}

When did the Fifth Circuit mandate issue?

June 21, 2018.^[11][12]

What was the regulatory effect?

The mandate vacated the 2016 fiduciary-rule package and restored the prior regulatory framework.^[11][12]

Does the Supreme Court certiorari clock run from the mandate?

No. It ordinarily runs from judgment, or from rehearing denial/subsequent judgment when that timely filing is involved.^[14]

What is the safest one-sentence rule?

After a DOL appellate panel rules, track five separate events—judgment, rehearing petition, rehearing disposition, mandate and any Supreme Court petition—because filing for rehearing delays procedural completion but does not itself erase the panel decision.

Sources & References

1. Legal Information Institute: Federal Rule of Appellate Procedure 40 — Panel Rehearing; En Banc Determination — https://www.law.cornell.edu/rules/frap/rule_40
2. Legal Information Institute: Federal Rule of Appellate Procedure 35 — Transferred to Rule 40 — https://www.law.cornell.edu/rules/frap/rule_35
3. Legal Information Institute: Federal Rule of Appellate Procedure 41 — Mandate: Contents; Issuance and Effective Date; Stay — https://www.law.cornell.edu/rules/frap/rule_41
4. U.S. House of Representatives — Office of the Law Revision Counsel: 28 U.S.C. §46 — Assignment of Judges; Panels; Hearings; Quorum — https://uscode.house.gov/view.xhtml?edition=prelim&num=0&req=granuleid%3AUSC-prelim-title28-section46
5. U.S. Court of Appeals for the Fifth Circuit: Fifth Circuit Rule 41.3 — Effect of Granting Rehearing En Banc — https://www.ca5.uscourts.gov/docs/default-source/default-document-library/5thcir-iop.pdf
6. U.S. Court of Appeals for the Fifth Circuit: Chamber of Commerce of the United States v. U.S. Department of Labor, 885 F.3d 360 (5th Cir. 2018) — https://www.ca5.uscourts.gov/opinions/pub/17/17-10238-cv0.pdf
7. California Department of Justice: States' Motion to Intervene — Chamber of Commerce v. DOL, April 26, 2018 — https://oag.ca.gov/system/files/attachments/press_releases/5th%20Motion%20to%20Intervene%20Filed.pdf
8. California Department of Justice: Proposed Intervenor States' Petition for Rehearing En Banc — Chamber of Commerce v. DOL, April 26, 2018 — https://oag.ca.gov/system/files/attachments/press_releases/5th%20En%20Banc%20Filed.pdf
9. California Department of Justice: States' Motion for Reconsideration of Denial of Intervention, May 16, 2018 — https://oag.ca.gov/system/files/attachments/press_releases/States%20Motion%20for%20Reconsideration.pdf
10. U.S. Court of Appeals for the Fifth Circuit / reproduced by Law.com: Order Denying Reconsideration and Alternative En Banc Relief, May 22, 2018 — https://images.law.com/contrib/content/uploads/documents/415/296490/ca5-denial-states-fiduciary.pdf
11. U.S. Department of Labor / Federal Register: Conflict of Interest Rule — Retirement Investment Advice: Notice of Court Vacatur, July 7, 2020 — https://www.federalregister.gov/documents/2020/07/07/2020-14260/conflict-of-interest-rule-retirement-investment-advice-notice-of-court-vacatur/
12. U.S. Department of Labor — Employee Benefits Security Administration: Improving Investment Advice for Workers and Retirees — https://www.dol.gov/agencies/ebsa/about-ebsa/our-activities/resource-center/fact-sheets/improving-investment-advice-for-workers-and-retirees
13. U.S. Court of Appeals for the Fifth Circuit: Order Granting Rehearing En Banc and Applying Fifth Circuit Rule 41.3, No. 26-50183 (2026) — https://www.ca5.uscourts.gov/docs/default-source/cm-ecf/26-50183.pdf
14. Supreme Court of the United States: Rules of the Supreme Court — Rule 13, Review on Certiorari: Time for Petitioning (2026) — https://www.supremecourt.gov/filingandrules/2026RulesoftheCourt_WEB.pdf
15. U.S. Chamber of Commerce: Chamber of Commerce v. U.S. Department of Labor — Fiduciary Rule Appeal — https://www.uschamber.com/cases/erisa/chamber-of-commerce-v-u-s-department-of-labor-fiduciary-rule-appeal

Educational Disclaimer

ROIStreet publishes educational content about 401(k) plans, ERISA, Department of Labor rulemaking and federal appellate procedure. This article is not legal, fiduciary, tax, investment, litigation, appellate, jurisdictional or plan-administration advice. Rehearing deadlines, en banc voting, mandate timing, intervention rights and Supreme Court deadlines depend on the applicable federal and local rules, docket orders, party status and procedural posture. Current deadlines should be verified against the operative appellate docket and current court rules before relying on them.

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