Buller v. Commissioner: The § 6213(a) Deficiency Petition Deadline as a Nonjurisdictional, Equitably Tollable Rule

I. Introduction

In Buller v. Commissioner, No. 24-1557 (2d Cir. Nov. 26, 2025) (as amended), the United States Court of Appeals for the Second Circuit fundamentally reshaped the law governing the timeliness of petitions to the United States Tax Court challenging notices of deficiency under Internal Revenue Code (I.R.C.) § 6213(a).

For decades, the Second Circuit (like virtually every other circuit) had described the 90‑day filing deadline in § 6213(a) as a rigid jurisdictional bar: if the taxpayer’s petition was even one day late, the Tax Court lacked power to hear the case, and no equitable relief was possible. In Buller, the court reversed course in light of the Supreme Court’s modern jurisprudence distinguishing jurisdictional rules from nonjurisdictional “claim-processing” rules.

The case arose when Mark Buller and Sarah Beatty received an IRS notice of deficiency for tax year 2018 on August 22, 2022. Their counsel filed the Tax Court petition nine days after the 90‑day statutory deadline. The IRS moved to dismiss for lack of jurisdiction; the Tax Court agreed and dismissed. On appeal, the Second Circuit addressed two principal questions:

Is § 6213(a)’s 90‑day deadline for filing a deficiency petition in the Tax Court a jurisdictional requirement?
If it is not jurisdictional, is that deadline subject to equitable tolling?

The Second Circuit answered both questions in favor of the taxpayers, holding that:

the § 6213(a) filing deadline is a nonjurisdictional claim-processing rule, and
that deadline is presumptively subject to equitable tolling.

The court therefore reversed the Tax Court’s dismissal and remanded for a determination, in the first instance, of whether Buller and Beatty can satisfy the substantive standard for equitable tolling.

The decision fits squarely within the Supreme Court’s broader effort over the last two decades to restrict the use of the word “jurisdiction” to provisions that Congress clearly intends to limit the adjudicatory power of courts, and to treat most filing deadlines instead as ordinary procedural rules that may admit equitable exceptions.

II. Summary of the Opinion

The Second Circuit (Judge Sullivan, joined by Judges Cabranes and Lohier) issued a structured opinion that proceeds in three main steps:

Background and Procedural Posture. The IRS mailed a notice of deficiency to Petitioners on August 22, 2022. Under § 6213(a), a taxpayer has 90 days to file a petition in the Tax Court. Petitioners filed their petition nine days late. The IRS moved to dismiss for lack of jurisdiction; the Tax Court agreed. Petitioners appealed, arguing the deadline is nonjurisdictional and subject to equitable tolling.
Holding 1 – The § 6213(a) deadline is nonjurisdictional. The court held that the 90‑day period in § 6213(a) is a nonjurisdictional claim-processing rule. Applying the Supreme Court’s “clear statement” approach to jurisdiction, the panel concluded:
- The statute’s text speaks only to the taxpayer’s obligation and the timeliness of the claim, not to the Tax Court’s power to adjudicate.
- The word “jurisdiction” does not appear in the operative sentence, and there is no explicit link between that deadline and the Tax Court’s jurisdiction.
- Prior Second Circuit cases calling the deadline “jurisdictional” did so without analysis and are not controlling after intervening Supreme Court decisions.
Holding 2 – The § 6213(a) deadline is subject to equitable tolling. Having found the deadline nonjurisdictional, the court held it is presumptively subject to equitable tolling, and nothing in § 6213(a) rebuts that presumption. Relying heavily on Boechler, P.C. v. Commissioner, 596 U.S. 199 (2022), the court found:
- The text of § 6213(a) does not expressly foreclose equitable tolling.
- The provision exists in an overall scheme designed to protect taxpayers, many of whom are unrepresented.
- Unlike the refund claim deadlines in § 6511 considered in United States v. Brockamp, 519 U.S. 347 (1997), § 6213(a) is not drafted in an unusually emphatic, complex, or exception-laden way that would signal a bar on tolling.
- Practical concerns about administrative burden and uncertainty are minimal, given the relatively small number of deficiency petitions compared to refund claims.

The court reversed the Tax Court’s dismissal and remanded for a factual and legal determination whether the particular circumstances of Petitioners’ late filing justify equitable tolling.

III. Detailed Analysis

A. Statutory and Procedural Context

I.R.C. § 6213(a) governs a taxpayer’s right to petition the Tax Court after receiving an IRS notice of deficiency. The key language provides:

Within 90 days, or 150 days if the notice is addressed to a person outside the United States, after the notice of deficiency ... is mailed ..., the taxpayer may file a petition with the Tax Court for a redetermination of the deficiency.

Two critical features of this regime are:

Prepayment forum. A deficiency petition gives the taxpayer a chance to challenge the IRS’s determination before paying the assessed tax. If the taxpayer misses the 90‑day window (and no equitable relief is available), the principal alternative is to pay the tax, file a refund claim, and then litigate in a refund suit.
Notice and timing. The 90‑day clock starts when the IRS “mails” the notice of deficiency, not when the taxpayer actually receives it. Weekends and District of Columbia holidays are excluded as the last day if they would otherwise be the deadline.

Historically, the Tax Court and most circuits treated the 90‑day period as an inflexible jurisdictional bar: if the petition was untimely by even one day, the Tax Court lacked jurisdiction, and no waiver, forfeiture, or equitable exception could apply. Buller calls that position into question within the Second Circuit.

B. Precedents Cited and Their Influence

1. The Second Circuit’s Own Prior Cases on § 6213(a)

The Second Circuit candidly acknowledges a “long” line of its own cases referring to § 6213(a)’s deadline as jurisdictional, including:

Galvin v. Commissioner, 239 F.2d 166 (2d Cir. 1956)
Vibro Manufacturing Co. v. Commissioner, 312 F.2d 253 (2d Cir. 1963)
Deutsch v. Commissioner, 599 F.2d 44 (2d Cir. 1979)
Tadros v. Commissioner, 763 F.2d 89 (2d Cir. 1985)
Hoffenberg v. Commissioner, 905 F.2d 665 (2d Cir. 1990)
Sicari v. Commissioner, 136 F.3d 925 (2d Cir. 1998)

These cases uniformly used the jurisdictional label, but crucially, they did so without conducting the type of text‑focused, clear-statement analysis that the Supreme Court later required in cases like Arbaugh and Henderson. They essentially assumed, rather than demonstrated, that § 6213(a) limited the Tax Court’s adjudicatory power.

Under ordinary horizontal stare decisis principles, a Second Circuit panel is bound by prior panel decisions. However, the court invokes a recognized exception: when intervening Supreme Court authority “casts doubt” on the controlling precedent, a later panel may depart from that precedent. See:

Lotes Co. v. Hon Hai Precision Industry Co., 753 F.3d 395, 405 (2d Cir. 2014)
In re Zarnel, 619 F.3d 156, 168 (2d Cir. 2010)

The court also cites Wilkins v. United States, 598 U.S. 152 (2023), where the Supreme Court held that earlier decisions that merely say a court is dismissing “for lack of jurisdiction” when a threshold fact is not met have no precedential effect on the jurisdictional question if they do not actually analyze jurisdiction.

Together, these authorities free the Buller panel to reassess § 6213(a) from first principles, unconstrained by its earlier, unreasoned jurisdictional labels.

2. Supreme Court’s Modern Jurisdiction/Claim‑Processing Jurisprudence

The heart of the opinion is the application of an extensive line of Supreme Court decisions that have “brought some discipline” to the term “jurisdiction”:

Arbaugh v. Y&H Corp., 546 U.S. 500 (2006)
Henderson ex rel. Henderson v. Shinseki, 562 U.S. 428 (2011)
United States v. Wong, 575 U.S. 402 (2015)
Fort Bend County v. Davis, 587 U.S. 541 (2019)
MOAC Mall Holdings LLC v. Transform Holdco LLC, 598 U.S. 288 (2023)
Wilkins v. United States, 598 U.S. 152 (2023)
Sebelius v. Auburn Regional Medical Center, 568 U.S. 145 (2013)
Boechler, P.C. v. Commissioner, 596 U.S. 199 (2022)

From these cases, several key principles emerge and are applied in Buller:

High bar for jurisdictional classification. As Wong puts it, “the Government must clear a high bar to establish that a [procedural rule] is jurisdictional.” Congress must clearly state that a threshold requirement limits a court’s adjudicatory capacity; a merely good or even “better” reading is not enough. See also MOAC Mall, 598 U.S. at 298.
Default rule: time bars are nonjurisdictional. The Court has repeatedly observed that “most time bars are nonjurisdictional” claim‑processing rules meant to promote orderly litigation, not to strip courts of power. Wong, 575 U.S. at 410.
Focus on text and context. Courts examine the statute’s text, structure, and placement, looking for a “clear tie” between the provision and a jurisdictional grant. See MOAC Mall, 598 U.S. at 300; Wong, 575 U.S. at 411.
Separation of filing deadlines from jurisdictional grants. When Congress places a filing deadline in a separate provision from the jurisdictional grant, that separation tends to indicate a lack of jurisdictional intent. Wong, 575 U.S. at 411.
Permissive language and audience. Provisions phrased in permissive language (e.g., “may file,” “may obtain a hearing”) and directed at the party (rather than the court) typically govern procedural obligations, not jurisdiction. See:
- Auburn, 568 U.S. at 154 (provider “may obtain a hearing” if request is filed within 180 days)
- Fort Bend, 587 U.S. at 551 (emphasis on whether requirements speak to courts’ authority or parties’ obligations).
Importance of clear jurisdictional language elsewhere in the statute. When Congress explicitly uses the term “jurisdiction” in some parts of a statute but not others, that contrast is probative. See Boechler, 596 U.S. at 208 (clear “no jurisdiction” clause in part of a statute highlights lack of clarity in adjacent provisions).

Boechler is particularly important because it involves the Tax Court and a similar structure. There the Supreme Court held that the 30‑day deadline in § 6330(d)(1) for filing a petition to review a “collection due process” (CDP) determination is:

nonjurisdictional, and
equitable tolling is available.

The Second Circuit relies on Boechler both as to methodology (applying the clear-statement rule) and as to the specific conclusion that analogous Tax Court deadlines can be treated as nonjurisdictional and tollable.

3. Brockamp and the Limits on Equitable Tolling of Tax Deadlines

The Commissioner invoked United States v. Brockamp, 519 U.S. 347 (1997), which held that the time limits in § 6511 for filing tax refund claims are not subject to equitable tolling. The Supreme Court in Brockamp found that § 6511:

sets forth its limitations “in unusually emphatic form,”
does so in “a highly detailed technical manner,”
reiterates the time limits “several times in several different ways,” and
contains multiple, express, detailed exceptions to those time limits.

That drafting, coupled with the enormous number of refund claims (over 90 million annually), persuaded the Court that Congress did not intend for courts to inject additional, judge-made equitable exceptions.

Buller (following Boechler and the Third Circuit’s Culp v. Commissioner) uses Brockamp as a contrast, not as a controlling analogy. The court emphasizes that § 6213(a):

is not drafted in the same emphatic or technically complex way,
contains fewer, less detailed exceptions, and
governs a much smaller and “ancillary” subset of tax disputes (roughly 21,000 deficiency petitions in 2023, per the Commissioner’s brief).

Those differences support the conclusion that the rationale of Brockamp does not extend to § 6213(a).

4. Third Circuit’s Culp Decision and Related Authority

The opinion also draws on the Third Circuit’s influential decision in Culp v. Commissioner, 75 F.4th 196 (3d Cir. 2023), which addressed the very same statutory provision. In Culp, the Third Circuit (also post‑Boechler) held that:

The § 6213(a) 90‑day deficiency petition deadline is nonjurisdictional, and
it is subject to equitable tolling.

Buller explicitly quotes Culp for two propositions:

The practical risk that a nonjurisdictional dismissal might “lock in” the deficiency under § 7459(d) is at most a “theoretical possibility” that is “seldom, if ever, to occur.” 75 F.4th at 202.
The differences between § 6511 (in Brockamp) and § 6213(a) – particularly in drafting style and number of exceptions – underscore that § 6213(a) is not carved out from the usual presumption of equitable tolling. Id. at 203–04.

Other Second Circuit cases, such as Borenstein v. Commissioner, 919 F.3d 746 (2d Cir. 2019) (standard of review), and Doe v. United States, 76 F.4th 64 (2d Cir. 2023) (equitable tolling standard), are also cited for supportive propositions.

C. The Court’s Legal Reasoning

1. Overcoming Prior Circuit Labels Through the “Fresh Eyes” Approach

A central methodological move in Buller is the explicit rejection of earlier Second Circuit descriptions of § 6213(a) as jurisdictional, on the ground that they were mere labels, not the product of the Supreme Court’s modern jurisdictional framework.

The panel notes:

Supreme Court decisions like Arbaugh, Henderson, Wong, and Boechler have newly clarified jurisdictional doctrine and imposed a “clear statement” requirement.
Wilkins instructs that a prior case that “simply states that the court is dismissing ‘for lack of jurisdiction’” when a threshold fact is missing should receive “no precedential effect” on the jurisdictional question.

Consequently, the panel “decide[s] with fresh eyes” whether § 6213(a)’s deadline actually limits the Tax Court’s jurisdiction. This is significant as a doctrinal matter: it signals that earlier, casual uses of the term “jurisdictional” will not control where they predate or ignore the Supreme Court’s reorientation of jurisdictional analysis.

2. Why § 6213(a)’s Deadline Is Nonjurisdictional

Applying the Supreme Court’s framework, the Second Circuit identifies several reasons why § 6213(a)’s deadline does not clearly speak in jurisdictional terms.

a. Text: “The taxpayer may file a petition”

The statutory language at issue provides that “the taxpayer may file a petition” within 90 days. The court notes:

The text “speaks only to a claim’s timeliness, not to a court’s power,” quoting Wong’s description of such language as “mundane statute-of-limitations language.”
The word “jurisdiction” is entirely absent from the sentence establishing the 90‑day period.
The “may file” phrasing, as in Auburn, is permissive and directed at the taxpayer; it does not purport to limit the Tax Court’s authority.

b. Audience and focus: obligations of the party, not power of the court

The opinion emphasizes that the deadline is:

directed at the taxpayer, and
concerned with what the taxpayer must do and when.

Under Fort Bend County v. Davis, provisions that “do not speak to a court’s authority or refer in any way to the jurisdiction of the ... courts,” but instead “speak to a party’s procedural obligations,” are properly treated as nonjurisdictional claim‑processing rules. 587 U.S. at 551.

c. Structural separation from jurisdictional grants

The court next notes that there is no “clear tie” between the 90‑day deadline and the Tax Court’s jurisdictional grants:

The deadline appears in a sentence that does not mention jurisdiction.
Elsewhere, Congress has explicitly conditioned Tax Court jurisdiction on timely filing. For example, § 6015(e)(1)(A) provides that the Tax Court “shall have jurisdiction” with respect to certain petitions only if filed within a specified time, language that the Second Circuit has previously treated as jurisdictional in Matuszak v. Commissioner, 862 F.3d 192, 196 (2d Cir. 2017).
That contrast – an explicit jurisdictional grant tied to a filing deadline in one provision, but not in § 6213(a) – is evidence that Congress did not intend to make the § 6213(a) deadline jurisdictional.

The court also observes that Congress has amended § 6213 multiple times since 1924 without specifying any jurisdictional consequence for the 90‑day deadline. This congressional silence, against the backdrop of the Supreme Court’s clear-statement rule, weighs against inferring jurisdictional intent.

d. The injunctive-relief “no jurisdiction” sentence in § 6213(a)

The Commissioner pointed to a later sentence in § 6213(a) that reads:

The Tax Court shall have no jurisdiction to enjoin any action or proceeding or order any refund under this subsection unless a timely petition for a redetermination of the deficiency has been filed ....

The argument was that this explicit “no jurisdiction” clause – conditioned on a timely petition – implied that the entire subsection, including the 90‑day filing requirement, must be understood as jurisdictional.

The Second Circuit rejects this argument, relying on:

Auburn: A requirement does not become jurisdictional “simply because it is placed in a section of a statute that also contains jurisdictional provisions.” 568 U.S. at 155.
Boechler: The presence of a clear jurisdictional statement in one part of a statute (here, regarding injunctions) “highlights the lack of such clarity” in the part governing the appeal deadline. 596 U.S. at 208.

Thus, if anything, the express “no jurisdiction” language as to injunctions supports, rather than undermines, the conclusion that Congress did not intend the filing deadline itself to be jurisdictional.

e. Prior uniform appellate treatment is not decisive

The Commissioner stressed that, until 2023, every federal appellate court to reach the question had held § 6213(a)’s deadline jurisdictional. The Second Circuit responds:

Supreme Court precedent allows a requirement to be treated as jurisdictional if there is a “long line of Supreme Court decisions” so holding and Congress leaves that line undisturbed. See Fort Bend, 587 U.S. at 548.
But no such line exists here; the Supreme Court has never held that § 6213(a)’s deadline is jurisdictional.
A “handful of lower court opinions” cannot substitute for a Supreme Court ruling, especially when they offer only “fleeting” jurisdictional references. See Wilkins, 598 U.S. at 165.

In the post‑Arbaugh framework, lower-court consensus, unsupported by explicit statutory text and Supreme Court authority, is inadequate to transform a deadline into a jurisdictional bar.

f. The § 7459(d) argument and the “locking in” of deficiencies

The Commissioner also invoked § 7459(d), which provides that a Tax Court decision “dismissing the proceeding shall be considered as its decision that the deficiency is the amount determined by the Secretary,” unless the dismissal is “for lack of jurisdiction.” On this view:

If § 6213(a) is nonjurisdictional and a petition is dismissed as untimely, that dismissal could be treated as a merits decision fixing the deficiency, potentially precluding later refund litigation.
By contrast, if the deadline is jurisdictional, a dismissal “for lack of jurisdiction” would not have that preclusive effect.

The Second Circuit, echoing the Third Circuit’s reasoning in Culp, treats this concern as a highly speculative, rarely arising hypothetical. It would require:

a late petition,
a nonjurisdictional dismissal,
full payment of the deficiency by the taxpayer,
a refund claim, and
a subsequent refund suit raising the same substantive issues.

The panel holds that even if the Commissioner’s reading of § 7459(d) were accepted, it would not change the jurisdictional analysis. In effect, the tail (a speculative preclusion scenario) cannot wag the dog (the clear-statement rule and the statutory text).

Accordingly, the court concludes that § 6213(a)’s 90‑day deadline is a nonjurisdictional claim-processing rule.

3. Why § 6213(a)’s Deadline Is Subject to Equitable Tolling

Once the court classifies the deadline as nonjurisdictional, the next question is whether it is subject to equitable tolling. Here, the court builds directly on Boechler.

a. Presumption of equitable tolling for nonjurisdictional limitations periods

The Supreme Court has described equitable tolling as a “traditional feature of American jurisprudence” and a “background principle” against which Congress drafts limitations periods. Boechler, 596 U.S. at 208–09.

The default rule is:

Nonjurisdictional limitations periods are presumptively subject to equitable tolling, unless Congress has clearly indicated otherwise.

Thus, once a time limit is found nonjurisdictional, the burden effectively shifts: the government must show that Congress intended to disallow equitable tolling.

b. Text and context of § 6213(a): no bar to tolling

The court finds that, like the CDP deadline in § 6330(d)(1) considered in Boechler, § 6213(a):

does not expressly prohibit equitable tolling,
contains a short time limit directed at the taxpayer, not the court, and
exists within a framework designed to be “unusually protective of taxpayers” in a setting where “laymen, unassisted by trained lawyers, often initiate the process.”

This context militates in favor of equitable tolling, particularly because many Tax Court petitioners are pro se, may face language or literacy barriers, and may be confused by IRS correspondence.

c. Distinguishing Brockamp yet again

The court reiterates the differences between § 6511 (in Brockamp) and § 6213(a):

§ 6511 is “unusually emphatic,” highly technical, and repeatedly reiterates its limits; § 6213(a) is not.
§ 6511 includes more numerous, explicit exceptions; § 6213(a)’s exceptions are “neither many nor set out explicitly or in a highly detailed technical manner,” and they do not cabin the amount of recovery.

These features convinced the Supreme Court that Congress did not want courts to add more exceptions to § 6511. By contrast, nothing about § 6213(a)’s design suggests an intent to withdraw the usual background availability of equitable tolling.

d. Administrative burden and systemic concerns

The Court in Brockamp also worried that allowing tolling of refund claim deadlines could destabilize tax administration, given the enormous volume of refund claims. In Buller, the Second Circuit relies on figures from the Commissioner’s brief to show:

Approximately one million taxpayers received deficiency notices in 2023.
Fewer than 21,000 deficiency petitions were filed in the Tax Court that year.
Over 90 million tax refunds were at issue in Brockamp.

The court concludes that equitable tolling for the “relatively small number of petitions” at issue in deficiency cases will not appreciably increase uncertainty or administrative burden. Nor is there reason to think that making tolling available will induce a wave of strategic late filings, given the demanding substantive standard for equitable tolling.

On these grounds, the court holds that § 6213(a)’s deadline is subject to equitable tolling.

4. Disposition: Reversal and Remand

Because the Tax Court assumed the deadline was jurisdictional, it did not reach the question whether Petitioners’ particular circumstances — including their counsel’s failure to meet the 90‑day deadline — justify tolling.

The Second Circuit therefore:

reverses the Tax Court’s dismissal, and
remands for the Tax Court to determine in the first instance whether Petitioners are entitled to equitable tolling.

On remand, the Tax Court will need to apply the usual equitable tolling criteria (diligence plus extraordinary circumstances) to the specific facts of Petitioners’ late filing.

IV. Impact and Broader Implications

A. Practical Consequences for Taxpayers

For taxpayers in the Second Circuit, Buller has several important implications:

Missed deadlines are no longer automatically fatal. A petition filed after the 90‑day period is not per se jurisdictionally barred. A taxpayer may argue that equitable tolling should apply, for example where:
- the IRS misaddressed or misled the taxpayer regarding the deadline,
- the taxpayer faced extraordinary obstacles (serious illness, imprisonment, natural disaster), or
- reliance on incorrect professional advice was coupled with diligent efforts to comply.
But equitable tolling will remain difficult to obtain. Equitable tolling is an extraordinary remedy, not a routine extension. Taxpayers must show both reasonable diligence and that some exceptional circumstance beyond their control prevented timely filing.
Potential for waiver or forfeiture by the IRS. Because the deadline is nonjurisdictional, the IRS could, in principle, waive or forfeit a timeliness objection by failing to raise it. In practice, the IRS almost always moves to dismiss late petitions, but Buller changes the theoretical landscape: the Tax Court is no longer compelled to raise timeliness sua sponte as a matter of jurisdiction.

B. Consequences for the Tax Court and the IRS

For the Tax Court, Buller means:

Timeliness under § 6213(a) is an affirmative, litigable issue, not a subject-matter jurisdiction prerequisite.
The court must now evaluate equitable tolling claims where timely raised, potentially involving:
- factual development (e.g., hearings on when the notice was reasonably received), and
- application of equitable standards developed in other contexts.

For the IRS:

Litigators will need to address both timeliness and tolling, including developing records on taxpayers’ diligence and circumstances leading to delay.
Internal guidance and training may need to reflect that, in the Second Circuit, § 6213(a)’s deadline is nonjurisdictional and that equitable tolling arguments must be anticipated.

C. Doctrinal Significance in Jurisdiction Theory

Buller is part of a broader line of cases constraining the overuse of jurisdictional labels. It:

Confirms that tax law is not exempt from the Supreme Court’s general approach to jurisdictional questions. The days of automatic, “tax exceptionalist” jurisdictional treatment for filing deadlines are fading.
Extends the logic of Boechler from the collection due process setting (§ 6330(d)(1)) to the core deficiency jurisdiction of the Tax Court (§ 6213(a)), a major component of the Tax Court’s docket.
Exemplifies how lower courts may lawfully depart from their own prior jurisdictional characterizations once the Supreme Court’s modern jurisprudence is applied.

This decision may further sharpen existing or emerging circuit splits on the jurisdictional status of § 6213(a), potentially inviting future Supreme Court review if other circuits persist in treating the deadline as jurisdictional post‑Boechler and post‑Culp.

D. Relationship to Refund Litigation and § 7459(d)

Although the court downplays the practical importance of § 7459(d) in this context, practitioners should be alert to:

The possibility that a nonjurisdictional dismissal for untimeliness could, under some readings of § 7459(d), be treated as a Tax Court decision that the deficiency equals the amount determined by the IRS.
The potential preclusion implications that might pose for subsequent refund suits in district court or the Court of Federal Claims.

At a minimum, Buller flags this as a conceptual issue, though it treats the actual risk as low.

V. Complex Concepts Simplified

A. Jurisdiction vs. Claim‑Processing Rules

In accessible terms:

A rule is jurisdictional if it goes to the court’s power to hear a case. If a requirement is jurisdictional:
- It cannot be waived by the parties.
- The court must raise it on its own if necessary.
- Equitable exceptions (like tolling, estoppel, or waiver) are generally unavailable.
A claim‑processing rule is a procedural rule that tells litigants how and when to proceed but does not limit the court’s basic authority. For such rules:
- Parties may waive or forfeit objections.
- Equitable doctrines (like equitable tolling) may apply, if Congress has not said otherwise.

The Supreme Court has insisted that “jurisdictional” be used sparingly and only where Congress clearly intends that result.

B. Equitable Tolling

Equitable tolling allows a court to treat a filing as timely, even though it was late, if:

The litigant has been diligent in trying to comply with the deadline; and
Some extraordinary circumstance beyond the litigant’s control prevented timely filing.

It is not a general license to ignore deadlines. Typical (non-exhaustive) examples that may justify tolling include:

Severe illness or incapacitation near the deadline.
Misleading or incorrect official information from the government about the deadline.
Unavoidable postal disruptions or disasters that make timely filing impossible.

By contrast, ordinary negligence, garden‑variety attorney error, or mere lack of knowledge of the law usually do not suffice.

C. Deficiency Petitions vs. Refund Suits

In tax litigation, there are two principal paths to court:

Deficiency petition (Tax Court) – prepayment:
- IRS issues a notice of deficiency.
- Taxpayer has 90 days (§ 6213(a)) to petition the Tax Court.
- Taxpayer need not pay the disputed tax first.
Refund suit (District Court or Court of Federal Claims) – post‑payment:
- Taxpayer pays the tax.
- Files an administrative refund claim within deadlines in § 6511.
- If denied (or not acted upon), taxpayer may sue for a refund.

A deficiency petition provides a more accessible and less financially burdensome avenue for many taxpayers. Hence, whether the § 6213(a) deadline is rigid or equitable can significantly affect taxpayers’ practical access to judicial review.

D. The “Clear Statement” Rule

The Supreme Court’s “clear statement” rule for jurisdiction means:

If a statute can reasonably be read in more than one way, and only one reading would make a requirement jurisdictional, courts must choose the nonjurisdictional interpretation unless Congress has clearly indicated the contrary.
Ambiguity is resolved against jurisdictional classification.

This rule is central to Buller: because § 6213(a) can be plausibly read as a simple filing deadline and lacks explicit jurisdictional language, it cannot meet the Supreme Court’s high threshold for being treated as jurisdictional.

VI. Conclusion

Buller v. Commissioner marks a major doctrinal and practical shift in Second Circuit tax jurisprudence. The court holds that:

The 90‑day filing deadline for Tax Court deficiency petitions in I.R.C. § 6213(a) is a nonjurisdictional claim‑processing rule, not a limit on the Tax Court’s adjudicatory power.
That deadline is subject to equitable tolling, consistent with the Supreme Court’s decisions in Boechler and the general presumption that nonjurisdictional limitations periods admit equitable exceptions absent clear contrary intent.

In reaching this result, the Second Circuit:

Aligns itself with the Supreme Court’s modern, text‑centered approach to jurisdictional questions.
Repudiates its own unreasoned, pre‑Arbaugh characterizations of § 6213(a) as jurisdictional.
Carefully distinguishes Brockamp and the refund claim deadlines in § 6511 from the more modest, less emphatic deficiency deadline in § 6213(a).

The opinion enhances procedural fairness by preserving the Tax Court’s ability to hear meritorious deficiency challenges in extraordinary circumstances, without significantly undermining the orderly administration of the tax system. It also continues the erosion of “tax exceptionalism” in jurisdictional doctrine, reinforcing that tax cases are subject to the same rigorous clear-statement standards as other federal litigation.

Going forward, taxpayers in the Second Circuit who miss the 90‑day deadline will have a narrow but meaningful opportunity to argue for equitable tolling. The Tax Court and the IRS must accordingly adapt to a regime in which timeliness under § 6213(a) is not an absolute jurisdictional bar, but a procedural requirement subject to traditional equitable principles.