(Slip Opinion)              OCTOBER TERM, 2007                                       1

                                       Syllabus

         NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
       being done in connection with this case, at the time the opinion is issued.
       The syllabus constitutes no part of the opinion of the Court but has been
       prepared by the Reporter of Decisions for the convenience of the reader.
       See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.


SUPREME COURT OF THE UNITED STATES

                                       Syllabus

 UNITED STATES v. CLINTWOOD ELKHORN MINING
                   CO. ET AL.

CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
                THE FEDERAL CIRCUIT

      No. 07–308.      Argued March 24, 2008—Decided April 15, 2008
The Internal Revenue Code requires a taxpayer seeking a refund of
  taxes unlawfully assessed to file an administrative claim with the In-
  ternal Revenue Service (IRS) before filing suit against the Govern-
  ment, see 26 U. S. C. §7422(a). Such claim must be filed within three
  years of the filing of a tax return or two years of the tax’s payment,
  whichever is later, see §6511(a). In contrast, the Tucker Act allows
  claims to be brought against the Government within six years of the
  challenged conduct. Respondent coal companies paid taxes on coal
  exports under a portion of the Code later invalidated under the Ex-
  port Clause of the Constitution. They filed timely administrative
  claims and recovered refunds of their 1997–1999 taxes, but sought a
  refund of their 1994–1996 taxes in the Court of Federal Claims with-
  out complying with the Code’s refund procedures. Nevertheless, the
  court allowed them to proceed directly under the Export Clause and
  the Tucker Act. Affirming in relevant part, the Federal Circuit ruled
  that the companies could pursue their Export Clause claim despite
  their failure to file timely administrative refund claims.
Held: The plain language of 26 U. S. C. §§7422(a) and 6511 requires a
 taxpayer seeking a refund for a tax assessed in violation of the Ex-
 port Clause, just as for any other unlawfully assessed tax, to file a
 timely administrative refund claim before bringing suit against the
 Government. Pp. 4–12.
    (a) Because the companies did not file a refund claim with the IRS
 for the 1994–1996 taxes, they may, under §7422(a), bring “[n]o suit”
 in “any court” to recover “any internal revenue tax” or “any sum” al-
 leged to have been wrongfully collected “in any manner.” Moreover,
 §6511’s time limits for filing administrative refund claims—set forth
2      UNITED STATES v. CLINTWOOD ELKHORN MINING CO.

                                  Syllabus

    in an “unusually emphatic form,” United States v. Brockamp, 519
    U. S. 347, 350—apply to “any tax imposed by [Title 26],” §6511(a)
    (emphasis added). Contrary to the companies’ claim that these stat-
    utes are ambiguous, the provisions clearly state that taxpayers must
    comply with the Code’s refund scheme before bringing suit, including
    the filing of a timely administrative claim. Indeed, this question was
    all but decided in United States v. A. S. Kreider Co., 313 U. S. 443,
    where the Court held that the limitations period in the Revenue Act
    then in effect, not the Tucker Act’s longer period, applied to tax re-
    fund actions. As was the case there, the current Code’s refund
    scheme would have “no meaning whatever,” id., at 448, if taxpayers
    failing to comply with it were nonetheless allowed to bring suit sub-
    ject only to the Tucker Act’s longer time bar. Pp. 4–6.
       (b) The companies nonetheless assert that their claims are exempt
    from the Code provisions’ broad sweep because the claims derive from
    the Export Clause. The principles that a “constitutional claim can
    become time-barred just as any other claim can,” Block v. North Da-
    kota ex rel. Board of Univ. and School Lands, 461 U. S. 273, 292, and
    that Congress has the authority to require administrative exhaustion
    before allowing a suit against the Government, even for a constitu-
    tional violation, see, e.g., Ruckelshaus v. Monsanto Co., 467 U. S. 986,
    1018, are fully applicable to unconstitutional taxation claims. The
    companies’ attempt to distinguish Export Clause claims on the
    ground that the Clause is not simply a limitation on taxing authority
    but a prohibition carving particular economic activity out of Con-
    gress’s power is without substance and totally manipulable. There is
    no basis for treating taxes collected in violation of that Clause differ-
    ently from taxes challenged on other grounds. Because the compa-
    nies acknowledge that their claims are subject to the Tucker Act’s
    time bar, the question is not whether their refund claim can be lim-
    ited, but rather which limitation applies. Their argument that, de-
    spite explicit and expansive statutory language, the Code’s refund
    scheme does not apply to their case as a matter of statutory interpre-
    tation is unavailing. They claim that Congress could not have in-
    tended it to apply a “constitutionally dubious” refund scheme to taxes
    assessed in violation of the Export Clause, but the statutory language
    emphatically covers the facts of this case. In any event, there is no
    constitutional problem. Congress’s detailed scheme is designed “to
    advise the appropriate officials of the demands or claims intended to
    be asserted, so as to insure an orderly administration of the revenue,”
    United States v. Felt & Tarrant Mfg. Co., 283 U. S. 269, 272, to pro-
    vide that refund claims are made promptly, and to allow the IRS to
    avoid unnecessary litigation by correcting conceded errors. Even
    when a tax’s constitutionality is challenged, taxing authorities have
                     Cite as: 553 U. S. ____ (2008)                    3

                                Syllabus

  an “exceedingly strong interest in financial stability,” McKesson Corp.
  v. Division of Alcoholic Beverages and Tobacco, Fla. Dept. of Business
  Regulation, 496 U. S. 18, 37, that they may pursue through provi-
  sions of the sort at issue. There is no reason why invoking the Export
  Clause would deprive Congress of the power to protect this interest.
  The companies’ claim that the Code procedures are excessively bur-
  densome is belied by their own invocation of those procedures for
  taxes paid within the Code’s limitations period, which resulted in full
  refunds with interest. Pp. 6–10.
     (c) The companies’ fallback argument—that even if the refund
  scheme applies to Export Clause cases generally, it does not apply
  when taxes are unconstitutional on their face—is rejected. Enochs v.
  Williams Packing & Nav. Co., 370 U. S. 1, distinguished. Pp. 10–12.
473 F. 3d 1373, reversed.

  ROBERTS, C. J., delivered the opinion for a unanimous Court.
                        Cite as: 553 U. S. ____ (2008)                              1

                             Opinion of the Court

     NOTICE: This opinion is subject to formal revision before publication in the
     preliminary print of the United States Reports. Readers are requested to
     notify the Reporter of Decisions, Supreme Court of the United States, Wash-
     ington, D. C. 20543, of any typographical or other formal errors, in order
     that corrections may be made before the preliminary print goes to press.


SUPREME COURT OF THE UNITED STATES
                                   _________________

                                   No. 07–308
                                   _________________


    UNITED STATES, PETITIONER v. CLINTWOOD 

        ELKHORN MINING COMPANY ET AL. 

 ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF 

           APPEALS FOR THE FEDERAL CIRCUIT

                                 [April 15, 2008] 


  CHIEF JUSTICE ROBERTS delivered the opinion of the
Court.
  The Internal Revenue Code provides that taxpayers
seeking a refund of taxes unlawfully assessed must comply
with tax refund procedures set forth in the Code. Under
those procedures, a taxpayer must file an administrative
claim with the Internal Revenue Service before filing suit
against the Government. Such a claim must be filed
within three years of the filing of a return or two years of
payment of the tax, whichever is later. The Tucker Act, in
contrast, is more forgiving, allowing claims to be brought
against the United States within six years of the chal-
lenged conduct. The question in this case is whether a
taxpayer suing for a refund of taxes collected in violation
of the Export Clause of the Constitution may proceed
under the Tucker Act, when his suit does not meet the
time limits for refund actions in the Internal Revenue
Code. The answer is no.
                          I
  A taxpayer seeking a refund of taxes erroneously or
unlawfully assessed or collected may bring an action
2   UNITED STATES v. CLINTWOOD ELKHORN MINING CO.

                     Opinion of the Court

against the Government either in United States district
court or in the United States Court of Federal Claims. 28
U. S. C. §1346(a)(1); EC Term of Years Trust v. United
States, 550 U. S. ___, ___, and n. 2 (2007) (slip op., at 2,
and n. 2). The Internal Revenue Code specifies that before
doing so, the taxpayer must comply with the tax refund
scheme established in the Code. United States v. Dalm,
494 U. S. 596, 609–610 (1990). That scheme provides that
a claim for a refund must be filed with the Internal Reve-
nue Service before suit can be brought, and establishes
strict timeframes for filing such a claim.
  In particular, 26 U. S. C. §7422(a) specifies:
       “No suit or proceeding shall be maintained in any
    court for the recovery of any internal revenue tax al-
    leged to have been erroneously or illegally assessed or
    collected, or of any penalty claimed to have been col-
    lected without authority, or of any sum alleged to
    have been excessive or in any manner wrongfully col-
    lected, until a claim for refund or credit has been duly
    filed with the [IRS].”
  The Code further establishes a time limit for filing such
a refund claim with the IRS: To receive a “refund of an
overpayment of any tax imposed by this title in respect of
which tax the taxpayer is required to file a return,” a
refund claim must be filed no later than “3 years from the
time the return was filed or 2 years from the time the tax
was paid, whichever of such periods expires the later.”
§6511(a). And §6511(b)(1) mandates that “[n]o credit or
refund shall be allowed or made” if a claim is not filed
within the time limits set forth in §6511(a). “Read to-
gether, the import of these sections is clear: unless a claim
for refund of a tax has been filed within the time limits
imposed by §6511(a), a suit for refund . . . may not be
maintained in any court.” Dalm, supra, at 602.
  In 1978, Congress levied a tax “on coal from mines
                 Cite as: 553 U. S. ____ (2008)           3

                     Opinion of the Court

located in the United States sold by the producer,” 26
U. S. C. §4121(a)(1), and specifically applied this tax to
coal exports, see §4221(a) (1994 ed.) (excepting from the
general ban on taxing exports those taxes imposed under,
inter alia, §4121). In 1998, a group of companies chal-
lenged the tax in the District Court for the Eastern Dis-
trict of Virginia, contending that it violated the Export
Clause of the Constitution. That Clause provides that “No
Tax or Duty shall be laid on Articles exported from any
State.” Art. I, §9, cl. 5. The District Court agreed and
held the tax unconstitutional. Ranger Fuel Corp. v.
United States, 33 F. Supp. 2d 466, 469 (1998). The Gov-
ernment did not appeal, and the IRS acquiesced in the
District Court’s holding. See IRS Notice 2000–28, 2000–1
Cum. Bull. 1116, 1116–1117 (IRS Notice).
   The respondents here, three coal companies, had all
paid taxes on coal exports under §4121(a) “[s]ince as early
as 1978.” App. to Pet. for Cert. 36a. After §4121(a) was
held unconstitutional as applied to coal exports, the com-
panies filed timely administrative claims in accordance
with the refund scheme outlined above, seeking a refund
of coal taxes they had paid in 1997, 1998, and 1999. The
IRS refunded those taxes, with interest.
   The companies also filed suit in the Court of Federal
Claims seeking a refund of $1,065,936 in taxes paid be-
tween 1994 and 1996. They did not file any claim for
those taxes with the IRS; any such claim would of course
have been denied, given the limits set forth in §6511. See
IRS Notice, at 1117 (“Claims [for a refund of taxes paid
under §4121] must be filed within the period prescribed by
§6511”). Notwithstanding the failure of the companies to
file timely administrative refund claims, the Court of
Federal Claims allowed the companies to pursue their suit
directly under the Export Clause. Jurisdiction rested on
the Tucker Act, 28 U. S. C. §1491(a)(1), and the companies
limited their claim to taxes paid within that statute’s 6-
4   UNITED STATES v. CLINTWOOD ELKHORN MINING CO.

                     Opinion of the Court

year limitations period, §2501 (2000 ed. and Supp. V).
   In allowing the companies to proceed outside the con-
fines of the Internal Revenue Code refund procedures, the
court relied on the decision of the Court of Appeals for the
Federal Circuit in Cyprus Amax Coal Co. v. United States,
205 F. 3d 1369 (2000). Andalex Resources, Inc. v. United
States, 54 Fed. Cl. 563, 564 (2002). The Court of Federal
Claims did not, however, allow the companies to recover
interest on the taxes paid under 28 U. S. C. §2411. That
provision requires the Government to pay interest “for any
overpayment in respect of any internal-revenue tax,” but
the court held that the statute applied only to refund
claims brought under the Code, not to claims brought
directly under the Export Clause. 54 Fed. Cl., at 566.
   The Court of Appeals affirmed in part and reversed in
part. It first refused to revisit its holding in Cyprus Amax,
and therefore upheld the ruling that the companies could
pursue their claim under the Export Clause, despite hav-
ing failed to file timely administrative refund claims. 473
F. 3d 1373, 1374–1375 (CA Fed. 2007). The Court of
Appeals reversed the Court of Federal Claims interest
holding, however, finding that the Government was re-
quired to pay the companies interest on the 1994–1996
amounts under §2411. Id., at 1376.
   We granted certiorari, 552 U. S. __ (2007), and now
reverse.
                                II 

                                A

   The outcome here is clear given the language of the
pertinent statutory provisions. Title 26 U. S. C. §7422(a)
states that “[n]o suit . . . shall be maintained in any court
for the recovery of any internal revenue tax alleged to have
been erroneously or illegally assessed or collected, or of
any penalty claimed to have been collected without author-
ity, or of any sum alleged to have been excessive or in any
                 Cite as: 553 U. S. ____ (2008)            5

                     Opinion of the Court

manner wrongfully collected, until a claim for refund . . .
has been duly filed with” the IRS. (Emphasis added.)
Here the companies did not file a refund claim with the
IRS for the 1994–1996 taxes, and therefore may bring
“[n]o suit” in “any court” to recover “any internal revenue
tax” or “any sum” alleged to have been wrongfully col-
lected “in any manner.” Five “any’s” in one sentence and
it begins to seem that Congress meant the statute to have
expansive reach.
   Moreover, the time limits for filing administrative re-
fund claims in §6511—set forth in an “unusually emphatic
form,” United States v. Brockamp, 519 U. S. 347, 350
(1997)—apply to “any tax imposed by this title,” 26
U. S. C. §6511(a) (emphasis added). The statute further
provides that “[n]o credit or refund shall be allowed or
made after the expiration of the period of limitation pre-
scribed in subsection (a) . . . unless a claim for credit or
refund is filed by the taxpayer within such period.”
§6511(b)(1). Again, this language on its face plainly covers
the companies’ claim for a “refund” of “tax[es] imposed by”
Title 26, specifically 26 U. S. C. §4121. The companies
argue that these statutory provisions are ambiguous, Brief
for Respondents 43–45, but we cannot imagine what lan-
guage could more clearly state that taxpayers seeking
refunds of unlawfully assessed taxes must comply with the
Code’s refund scheme before bringing suit, including the
requirement to file a timely administrative claim.
   Indeed, we all but decided the question presented over
six decades ago in United States v. A. S. Kreider Co., 313
U. S. 443 (1941). Section 1113(a) of the Revenue Act of
1926, like the refund claim provision in §7422(a) of the
current Code, prescribed that “[n]o suit or proceeding shall
be maintained in any court for the recovery of any inter-
nal-revenue tax alleged to have been erroneously or ille-
gally assessed or collected, or of any penalty claimed to
have been collected without authority, or of any sum
6   UNITED STATES v. CLINTWOOD ELKHORN MINING CO.

                     Opinion of the Court

alleged to have been excessive or in any manner wrong-
fully collected until a claim for refund or credit has been
duly filed with the Commissioner of Internal Revenue,”
and established a time limit for bringing suit once the
claim-filing requirement had been met. 44 Stat. 116. Like
the companies here, A. S. Kreider had failed to file a tax-
refund action within that limitations period. See 313
U. S., at 446. And, like the companies here, A. S. Kreider
argued that it was instead subject only to the longer 6-
year statute of limitations under the Tucker Act. Id., at
447.
  We rejected the claim, holding that the Tucker Act
limitations period “was intended merely to place an out-
side limit on the period within which all suits must be
initiated” under that Act, and that “Congress left it open
to provide less liberally for particular actions which, be-
cause of special considerations, required different treat-
ment.” Ibid. We held that the limitations period in
§1113(a) was “precisely that type of provision,” finding
that Congress created a shorter statute of limitations for
tax claims because “suits against the United States for the
recovery of taxes impeded effective administration of the
revenue laws.” Ibid. If such suits were allowed to be
brought subject only to the 6-year limitations period in the
Tucker Act, we explained, §1113(a) would have “no mean-
ing whatever.” Id., at 448. So too here. The refund
scheme in the current Code would have “no meaning
whatever” if taxpayers failing to comply with it were
nonetheless allowed to bring suit subject only to the
Tucker Act’s longer time bar.
                              B
  The companies gamely argue for a different result here
because the coal tax at issue was assessed in violation of
the Export Clause of the Constitution. They spend much
of their brief arguing that the Export Clause itself creates
                 Cite as: 553 U. S. ____ (2008)           7

                     Opinion of the Court

a cause of action against the Government, which can be
brought directly under the Tucker Act. See Brief for Re-
spondents 8–25. We need not decide this question here,
because it does not matter. If the companies’ claims are
subject to the Code provisions, those claims are barred
whatever the source of the cause of action. We there-
fore turn to the companies’ assertion that their claims
are somehow exempt from the broad sweep of the Code
provisions.
   The companies do not argue for such an exemption
simply because their claims are based on a constitutional
violation. As they acknowledge, id., at 34, a “constitu-
tional claim can become time-barred just as any other
claim can,” Block v. North Dakota ex rel. Board of Univ.
and School Lands, 461 U. S. 273, 292 (1983). Further,
Congress has the authority to require administrative
exhaustion before allowing a suit against the Government,
even for a constitutional violation. See, e.g., Ruckelshaus
v. Monsanto Co., 467 U. S. 986, 1018 (1984); Christian v.
New York State Dept. of Labor, 414 U. S. 614, 622 (1974);
Aircraft & Diesel Equipment Corp. v. Hirsch, 331 U. S.
752, 766–767 (1947).
   These principles are fully applicable to claims of uncon-
stitutional taxation, a point highlighted by what we have
said in other cases about the Anti-Injunction Act. That
statute commands that (absent certain exceptions) “no suit
for the purpose of restraining the assessment or collection
of any tax shall be maintained in any court.” 26 U. S. C.
§7421(a). The “decisions of this Court make it unmistaka-
bly clear that the constitutional nature of a taxpayer’s
claim . . . is of no consequence” to whether the prohibition
against tax injunctions applies. Alexander v. “Americans
United” Inc., 416 U. S. 752, 759 (1974). This is so even
though the Anti-Injunction Act’s prohibitions impose upon
the wronged taxpayer requirements at least as onerous as
those mandated by the refund scheme—the taxpayer must
8   UNITED STATES v. CLINTWOOD ELKHORN MINING CO.

                      Opinion of the Court

succumb to an unconstitutional tax, and seek recourse
only after it has been unlawfully exacted. We see no
reason why compliance with straightforward administra-
tive requirements and reasonable time limits to seek a
refund once a tax has been paid should lead to a different
result.
   The companies assert that Export Clause claims in
particular must be treated differently from constitutional
claims in general. This is so, they argue, because the
Clause is not simply a limitation on the taxing authority
but a prohibition that “carves one particular economic
activity completely out of Congress’s power.” Brief for
Respondents 11. That distinction is without substance
and totally manipulable: If the pertinent authority is
regarded as the power to tax exports, the Clause is indeed
a complete prohibition on congressional power. But if the
pertinent authority is instead viewed as the “Power To lay
and collect Taxes,” U. S. Const., Art. I, §8, cl. 1, then the
Clause is properly regarded as a limitation on that power.
We do not question the importance of the Export Clause to
the success of the enterprise in Philadelphia in 1787, see
Brief for Respondents 11–13, but we see no basis for treat-
ing taxes collected in violation of its terms differently from
taxes challenged on other grounds.
   Indeed, the companies more or less give up the game
when they acknowledge that their claims are subject to
the Tucker Act’s statute of limitations. See id., at 34. The
question is thus not whether the companies’ refund claim
under the Export Clause can be limited, but rather which
limitation applies. The companies are therefore left to
argue that, despite the explicit and expansive statutory
language described above, the refund scheme in Title 26
does not apply to their case as a matter of statutory inter-
pretation. We find this ambitious argument unavailing.
   The companies seek to support it by characterizing the
refund scheme set out in the Code as “pro-government and
                 Cite as: 553 U. S. ____ (2008)           9

                     Opinion of the Court

revenue-protective,” and therefore “constitutionally dubi-
ous” as applied to Export Clause cases. Id., at 28–29.
Given this potential constitutional infirmity, the compa-
nies argue, Congress could not have intended the refund
scheme to apply to taxes assessed in violation of the Ex-
port Clause. See Ashwander v. TVA, 297 U. S. 288, 341
(1936) (Brandeis, J., concurring). We disagree. To begin
with, any argument that Congress did not mean to require
those in the companies’ position to comply with the tax
refund scheme runs into a powerful impediment, for “[t]he
‘strong presumption’ that the plain language of the statute
expresses congressional intent is rebutted only in ‘rare
and exceptional circumstances.’ ” Ardestani v. INS, 502
U. S. 129, 135 (1991) (quoting Rubin v. United States, 449
U. S. 424, 430 (1981)). As we have already explained, the
language of the relevant statutes emphatically covers the
facts of this case.
   In any event, we see no constitutional problem at all.
Congress has indeed established a detailed refund scheme
that subjects complaining taxpayers to various require-
ments before they can bring suit. This scheme is designed
“to advise the appropriate officials of the demands or
claims intended to be asserted, so as to insure an orderly
administration of the revenue,” United States v. Felt &
Tarrant Mfg. Co., 283 U. S. 269, 272 (1931), to provide
that refund claims are made promptly, and to allow the
IRS to avoid unnecessary litigation by correcting conceded
errors. Even when the constitutionality of a tax is chal-
lenged, taxing authorities do in fact have an “exceedingly
strong interest in financial stability,” McKesson Corp. v.
Division of Alcoholic Beverages and Tobacco, Fla. Dept. of
Business Regulation, 496 U. S. 18, 37 (1990), an interest
they may pursue through provisions of the sort at issue
here.
   We do not see why invocation of the Export Clause
would deprive Congress of the power to protect this “ex-
10   UNITED STATES v. CLINTWOOD ELKHORN MINING CO.

                     Opinion of the Court

ceedingly strong interest.” Congress may not impose a tax
in violation of the Export Clause (or any other constitu-
tional provision, for that matter). But it is certainly
within Congress’s authority to assure that allegations of
taxes unlawfully assessed—whether the asserted illegality
is based upon the Export Clause or any other provision of
law—are processed in an orderly and timely manner, and
that costly litigation is avoided when possible. The com-
panies’ claim that the Code procedures are themselves
excessively burdensome is belied by the companies’ own
invocation of those procedures for taxes paid within the
Code’s limitations period, which resulted in full refunds
with interest.
                              C
   As a fallback argument, the companies maintain that
even if the refund scheme applies to Export Clause cases
generally, it does not “apply to taxes that are, on their
face, unconstitutional.” Brief for Respondents 39. They
rely for this proposition on Enochs v. Williams Packing &
Nav. Co., 370 U. S. 1 (1962), a case dealing with the Anti-
Injunction Act, 26 U. S. C. §7421(a). Despite that Act’s
broad and mandatory language, we explained that “if it is
clear that under no circumstances could the Government
ultimately prevail, . . . the attempted collection may be
enjoined if equity jurisdiction otherwise exists. In such a
situation the exaction is merely in ‘the guise of a tax.’ ”
370 U. S., at 7 (quoting Miller v. Standard Nut Margarine
Co. of Fla., 284 U. S. 498, 509 (1932)). See also Bob Jones
Univ. v. Simon, 416 U. S. 725, 745–746 (1974) (reaffirming
the “under no circumstances” rule of Williams Packing).
   On the force of Williams Packing, the companies argue
that the refund scheme should similarly be read as inap-
plicable to situations in which there are “no circum-
stances” under which the tax imposed could be held valid
under the Export Clause. The trouble with this is that
                  Cite as: 553 U. S. ____ (2008)           11

                      Opinion of the Court

§7422, the primary statute governing the refund process,
is written much more broadly than §7421(a), the statute at
issue in Williams Packing. Section §7422(a) states that
“[n]o suit . . . shall be maintained in any court for the
recovery of any internal revenue tax alleged to have been
erroneously or illegally assessed or collected . . . until a
claim for refund or credit has been duly filed with the”
IRS. (Emphasis added.) This language generally tracks
that of the Anti-Injunction Act, which also applies to suits
“restraining the assessment or collection of any tax.”
§7421(a) (emphasis added). But §7422(a) goes on to apply
its prohibition against suit absent a proper refund claim to
“any sum alleged to have been excessive or in any manner
wrongfully collected.” (Emphasis added.) Even if we
agreed that a facially unconstitutional tax for purposes of
the tax refund scheme is “merely in ‘the guise of a tax,’ ”
Williams Packing, supra, at 7 (quoting Standard Nut
Margarine, supra, at 509), and therefore not a “tax alleged
to have been erroneously or illegally assessed or collected,”
§7422(a), it would nevertheless clearly fall into the
broader category of “any sum . . . in any manner wrong-
fully collected,” ibid.
   Moreover, even if we were to accept the companies’
argument that the “under no circumstances” limitation on
the Anti-Injunction Act applies to the refund scheme, they
still would not prevail. We made clear in Williams Pack-
ing that “the question of whether the Government has a
chance of ultimately prevailing is to be determined on the
basis of the information available to it at the time of suit.
Only if it is then apparent that, under the most liberal
view of the law and the facts, the United States cannot
establish its claim, may the suit for an injunction be main-
tained.” 370 U. S., at 7. A tax injunction suit, of course, is
brought at the time the Government attempts to assess a
tax on the taxpayer. Thus, if we applied the Williams
Packing “under no circumstances” rule to the refund
12   UNITED STATES v. CLINTWOOD ELKHORN MINING CO.

                      Opinion of the Court

scheme, we would judge the Government’s chances of
success as of the time the tax was assessed.
  In this case, the companies seek refunds for taxes paid
between 1994 and 1996. At that time, the scope of the
Export Clause was sufficiently debatable that we granted
certiorari in 1996, see United States v. International Busi-
ness Machines Corp., 517 U. S. 843, and again in 1998, see
United States v. United States Shoe Corp., 523 U. S. 360,
to clear it up. What is more, the District Court that struck
down the application of §4121(a) to coal exports partially
relied on these cases in arriving at its decision, Ranger
Fuel Corp., 33 F. Supp. 2d, at 469, and the IRS cited, inter
alia, International Business Machines, supra, in its acqui-
escence notice, see IRS Notice, at 1116. Indeed, we would
think that if the unconstitutionality of the coal export tax
were so obvious that the Government had no chance of
prevailing, someone paying the tax—such as these compa-
nies—would have successfully challenged it earlier than
20 years after its enactment.
  We therefore hold that the plain language of 26 U. S. C.
§§7422(a) and 6511 requires a taxpayer seeking a refund
for a tax assessed in violation of the Export Clause, just as
for any other unlawfully assessed tax, to file a timely
administrative refund claim before bringing suit against
the Government. Because we find that the Court of Ap-
peals erred in allowing the companies to bring suit seeking
a refund for the 1994–1996 taxes, we do not reach the
question whether the Court of Appeals also erred in
awarding the companies interest on those amounts under
28 U. S. C. §2411. The judgment of the Court of Appeals is
reversed.
                                             It is so ordered.
