; 
see also
Balestra, 119 Fed. Cl. at 110
.

      In January 2008, Mr. and Mrs. Bates filed a refund claim with the IRS
concerning their 2004 taxes, Ex. B to Def.’s 1st Mot. at 1. They sought a refund of
FICA taxes in the amount of $12,936.26, which they calculated by applying the
1.45% HI tax rate to the benefits Mr. Bates actually received and subtracting this
amount from the taxes that were paid based on the estimated nonqualified plan


2 See Ex. C to Ex. 2 to Mot. for Summ. J., United States v. Bates, No. 8:12-CV-833-
CEH-TBM (M.D. Fla., Dec. 4, 2014), ECF No. 30-3 at 50 (Mr. Bates’s 2003 W-2
form, showing Medicare wages and Medicare tax withheld including the amounts
attributable to the nonqualified deferred compensation plan).
                                         -2-
benefits.
 Id. at 1–2. 
The IRS denied their claim in May 2008, 3 and a little more
than one year later Mr. Bates was named as one of 170 pro se plaintiffs who had
joined their claims in this case. See Compl. at 1–2. Due to an apparent
misunderstanding concerning the proper procedure to be followed in this unusual
circumstance of a case with numerous pro se parties, only William Koopmann
signed the initial complaint. See
 id. at 17; 
Order (May 26, 2010) at 2. A signature
page for Mr. Bates, on which he indicated that Mrs. Bates was also a party, was
submitted on August 12, 2009, and was subsequently filed as an amendment to the
complaint, as of the date of submission. See Am. to Compl. at 11, ECF No. 59;
Order (May 26, 2010) at 4–5. A second case purporting to contain the refund claim
of Mr. Bates and 47 other pro se taxpayers was filed the following year, on March
12, 2010. See Compl., Sofman v. United States, No. 10-157T, at 1 & Ex. 8 at 1. In
addition to these two cases, Mr. and Mrs. Bates also filed with the IRS Office of
Appeals an administrative appeal of the denial of their refund claim, and on May
17, 2010 received a refund in the amount requested, plus interest. Exs. C and D to
Def.’s 1st Mot.

        Eight months later, the IRS sent Mr. and Mrs. Bates a letter informing them
that the refund was erroneous and requesting its return. Ex. D to
 id. The IRS
maintained that the refund claim was filed too late, and that it lost the authority to
approve the request once the claim was in litigation.
 Id. Mister Bates 
responded
that he would only return the refunded amount, plus any applicable interest, if he
were to lose his litigation in our court. Ex. E to Def.’s 1st Mot. Fourteen months
later, the United States sued Mr. and Mrs. Bates in the U.S. District Court for
Middle District of Florida, seeking to recover the refund, plus interest, under the
erroneous refund provision of the tax code, 26 U.S.C. § 7405. Ex. F to Def.’s 1st
Mot. Following a bench trial, the government obtained a judgment against Mr. and
Mrs. Bates for the return of the refund with interest. United States v. Bates, No.
8:12-CV-833-T-36TBM, 
2015 WL 7444285
, at *5 (M.D. Fla. Nov. 23, 2015). In that
decision, the court found that, because the Bates plaintiffs filed their refund request
after the statute of limitations period under 26 U.S.C. § 6511 had expired, the
refund was improperly granted.
 Id. at *4–5.
       The government contends that the district court decision, finding that Mr.
and Mrs. Bates were not entitled to a refund of the taxes at issue, precludes them
from litigating their claim in this court. Second Mot. by U.S. to Dismiss Claims
Filed by Mr. and Mrs. Bates (Def.’s 2d Mot.), ECF No. 90 at 3–6. Defendant argues
that this decision precludes the claim of Mr. and Mrs. Bates for two reasons. First,
under the doctrine of claim preclusion, defendant maintains that the final decision
on the merits by the district court regarding the tax refund at issue precludes our
court from hearing any issue that could have been raised in the district court.
 Id. at


3 
See Compl., Sofman v. United States, No. 10-157T, Ex. 8 at 2 (first page of IRS
letter bearing May 9, 2008 date).
                                         -3-
3–5. Under this theory, Mr. and Mrs. Bates fail to state a claim upon which relief
may be granted as a consequence of the district court decision, warranting a
dismissal under RFCF 12(b)(6).

       Second, the government argues that Mr. and Mrs. Bates are collaterally
estopped from bringing their claim in this court, because the issue of the timeliness
of their refund request was actually litigated in the district court and resolved
against them.
 Id. at 5–6 
(citing Laguna Hermosa Corp. v. United States, 
671 F.3d
1284
, 1288 (Fed. Cir. 2012)). As the timely filing of a refund request is a
jurisdictional predicate for a refund claim to be entertained in our court or a district
court, see United States v. Dalm, 
494 U.S. 596
, 609 (1990); Stephens v. United
States, 
884 F.3d 1151
, 1159–60 (Fed. Cir. 2018), if the litigation of this particular
issue is precluded, dismissal for lack of subject-matter jurisdiction would be proper
under RCFC 12(b)(1).

       In their response, Mr. and Mrs. Bates do not directly address the
government’s claim preclusion argument. See Pls.’ Reply to Def.’s 2d Mot. (Pls.’
Resp.), ECF No. 96 at 1–6. They do, however, question whether preclusion could
apply to their claim in this earlier-filed lawsuit, and maintain that they were given
no opportunity in the district court to litigate their claim that the HI taxes at issue
were unlawful collections of future years’ taxes on income that was never to be
received by them.
 Id. at 4–6. 
Regarding issue preclusion, Mr. and Mrs. Bates argue
that under Commissioner of Internal Revenue v. Sunnen, 
333 U.S. 591 
(1948),
collateral estoppel can only apply in tax cases when the matters in the two cases are
“identical in all respects.”
 Id. at 2 
(quoting 
Sunnen, 333 U.S. at 599
–600). They
maintain this identity is lacking, as the district court considered only whether they
“had the right to a refund for the 2004 tax year,”
 id. at 3, 
and found the particular
refund issued by the IRS to be erroneous because their claim was not timely filed,

id. at 4. 
They argue that the essential matters in our case---the merits of their
refund claim, which they characterize as applying to tax years after 2004---were not
addressed by the district court.
 Id. at 5–6
.

      The government, in reply, argues that claim preclusion applies because both
lawsuits concern the same facts and transactions, namely whether Mr. and Mrs.
Bates were entitled to the FICA tax refund they requested. Def.’s Reply in Supp. of
Second Mot. to Dismiss (Def.’s Reply), ECF No. 97 at 2–3. Regarding issue
preclusion, defendant contends that, regardless of the tax years that Mr. and Mrs.
Bates contend are at issue, both cases involve the same factual and legal issue---
whether the tax refund claim, filed to recover the HI payments made by United,
was timely filed.
 Id. at 3
–4. 4


4 At the Court’s request, see Order (Jan.17, 2017), ECF No. 101, the parties filed
supplemental briefs addressing the potential applicability of 26 U.S.C.
§ 6331(i)(4)(A), which prevents the federal government from filing a lawsuit to
                                          -4-
                                  II. DISCUSSION

A. Legal Standards for Issue and Claim Preclusion

        Under the doctrine of claim preclusion, “[a] final judgment on the merits of an
action precludes the parties or their privies from relitigating issues that were or
could have been raised in that action.” Federated Dep't Stores, Inc. v. Moitie, 
452
U.S. 394
, 398 (1981) (citing 
Sunnen, 333 U.S. at 597
–98; Cromwell v. Cty. of Sac, 
94
U.S. 351
, 352–53, 
24 L. Ed. 195 
(1877)). Claim preclusion employs the common law
concepts of merger and bar, see Migra v. Warren City Sch. Dist. Bd. of Educ., 
465
U.S. 75
, 77 n. 1 (1984), and is not limited to the legal theories litigated but extends
to all remedies concerning the “particular factual transaction or series thereof on
which a suit is brought.” Foster v. Hallco Mfg. Co., 
947 F.2d 469
, 479 (Fed. Cir.
1991). Under issue preclusion, or collateral estoppel, “once an issue is actually and
necessarily determined by a court of competent jurisdiction, that determination is
conclusive in subsequent suits based on a different cause of action involving a party
to the prior litigation.” Montana v. United States, 
440 U.S. 147
, 153 (1979).

B. The Government’s Motion to Dismiss the Bateses’ Claim

       The Court addresses issue preclusion first, because the government’s
argument, if successful, would deprive this Court of subject-matter jurisdiction. See
Steel Co. v. Citizens for a Better Env’t, 
523 U.S. 83
, 93–95 (1998) (holding that a
court must first be satisfied that it has jurisdiction before any merits questions may
be reached); Chisolm v. United States, 
82 Fed. Cl. 185
, 192 (2008) (same). Issue
preclusion applies when: (1) the issue is identical to one decided in the first action;
(2) the issue was actually litigated in the first action; (3) resolution of the issue was
essential to a final judgment in the first action; and (4) the plaintiff had a full and
fair opportunity to litigate the issue in the first action. Laguna 
Hermosa, 671 F.3d
at 1288
.

       Mister and Mrs. Bates suggest that collateral estoppel should apply only to
parties who were plaintiffs in the first action, see Pls.’ Resp. at 2, although this is
clearly not the law. See, e.g., United States v. Stauffer Chem. Co., 
464 U.S. 165
,
167–69 (1984) (applying collateral estoppel against the federal government when it
had been the defendant in the first action). They also question whether collateral
estoppel may apply in a lawsuit that was filed prior to the one whose final judgment
is invoked as the basis for issue preclusion. Pls.’ Resp. at 3. But the Federal Circuit

collect unpaid payroll taxes while a suit for the refund of the paid portion of such
taxes is pending. See Suppl. Br. in Supp. of 2d Mot. (Def.’s Suppl. Br.), ECF No.
104; Reply to Suppl. Br. (Pls.’ Suppl. Br.), ECF No. 109. The Court concludes that
the statute does not apply in our context, as the district court case was not to collect
unpaid taxes, but rather to collect a portion of paid taxes that was allegedly
erroneously refunded. See 26 U.S.C. § 7405.
                                          -5-
has squarely held that once a final judgment is entered concerning an issue, this
will apply in proceedings that started earlier than or concurrently with the case
that had reached finality---even if the issue was already decided to the contrary (but
not with finality) in those other proceedings. See Mendenhall v. Barber-Greene Co.,
26 F.3d 1573
, 1576–80 (Fed. Cir. 1994). More substantively, Mr. and Mrs. Bates
also invoke the “separable facts” doctrine from Sunnen, which limits the
applicability of collateral estoppel in cases involving different tax years and
different transactions or contracts. See Pls.’ Resp. at 2–3. 5 But that doctrine is
irrelevant to the claim of Mr. and Mrs. Bates, which is not based on multiple tax
refund requests and multiple, distinguishable nonqualified plans.

       In opposing the government’s motion, Mr. and Mrs. Bates focus on issues that
were not litigated in the district court, such as their merits argument that a portion
of the HI tax paid by United was an illegal prepayment of taxes on never-realized
income for future tax years; or on the difference in the cause of action in the district
court, a suit to recover a refund rather than one seeking a refund.
 Id. 4–6. But
what is identical in both lawsuits is that both concern whether Mr. and Mrs. Bates
were entitled to a tax refund based on the refund request they submitted in
January 2008. See Bates, 
2015 WL 7444285
, at *2 (discussing request received by
the IRS on January 28, 2008); Am. to Compl. at 11, ECF No. 59 (the Bateses’
signature page, indicating the refund was requested on January 24, 2008); Ex. B to
Def.’s 1st Mot. (the refund request). The government notes that the reason the
district court found the tax refund to have been erroneously issued was that the tax
refund request filed by Mr. and Mrs. Bates was not timely, under 26 U.S.C. § 6511.
Def.’s 2d Mot. at 5–6; see Bates, 
2015 WL 7444285
, at *4–5. This point is conceded
by Mr. and Mrs. Bates, who state that the district court “only settled the question of
whether the refund was ‘erroneous’ because the claim was untimely filed.” Pls.’
Resp. at 4.

       The problem for Mr. and Mrs. Bates is that the limitation period in 26 U.S.C.
§ 6511(a) also applies to determine whether a tax refund request was timely for
purposes of our court’s jurisdiction. See 26 U.S.C. § 7422(a); 
Dalm, 494 U.S. at 601
–
02, 609–10; 
Stephens, 884 F.3d at 1154
. The district court’s determination that the
refund request was filed beyond the section 6511 limitations period was without
question actually litigated and essential to the judgment in that case, and Mr. and
Mrs. Bates had a full and fair opportunity to litigate that issue---indeed, the district
court considered their argument that the timing of United’s bankruptcy should be
taken into account. See Bates, 
2015 WL 7444285
, at *4–5. 6 Although Mr. and Mrs.

5 To explain the Sunnen doctrine, Mr. and Mrs. Bates rely upon a U.S. Tax Court
decision, although the appellate opinion in that case questioned whether the
“separable facts” doctrine was still good law. See Peck v. Comm’r, 
904 F.2d 525
, 527
(9th Cir. 1990) (discussing 
Montana, 440 U.S. at 161
).

6   Since the district court found “no dispute” concerning the untimeliness of the
                                          -6-
Bates argue that they are seeking in this case a refund of taxes for different tax
years than were at issue in the district court, Pls.’ Resp. at 5, the refund that was
recouped in that case and the refund that is sought in this case are for the identical
taxes paid by United and are based on the same tax refund request submitted by
Mr. and Mrs. Bates---which identified 2004 as the applicable tax year. See Ex. B to
Def.’s 1st Mot. at 1. To the extent that Mr. and Mrs. Bates believe that the refund
request pertained to later tax years, and thus was not untimely, that argument was
relevant to whether the refund they received was erroneously issued and should
have been raised in the district court.

        Finally, Mr. and Mrs. Bates also contend that the timeliness of their refund
request was “not essential” to their claim in this case. Pls.’ Resp. at 6. But the
predicate of a timely-filed refund request is a jurisdictional requirement for a tax
refund claim to be entertained in our court, see 
Dalm, 494 U.S. at 601
–02, 609–10;
Stephens, 884 F.3d at 1154
–56, 1159–60; and the issue of a court’s jurisdiction is a
threshold matter that is essential to every case, see Steel Co., 523 U.S at 94–95.
The district court has determined that the tax refund request submitted by Mr. and
Mrs. Bates, which was the basis for the refund at issue in that court and the
identical one at issue here, was filed too late under 26 U.S.C. § 6511(a). As a
consequence, this Court is precluded from allowing that issue to be relitigated in
this case and has no choice but to grant the government’s motion to dismiss the
claim of Mr. and Mrs. Bates for lack of subject-matter jurisdiction. 7 Although it
appears that Mr. and Mrs. Bates, representing themselves in the district court as
well as in this court, chose not to appeal the district court’s decision because they
believed that their refund could be litigated in this court, see Pls.’ Suppl. Br. at 7,
this is unfortunately not the case. The government’s motion to dismiss their claim,
under RCFC 12(b)(1), is accordingly GRANTED.

                                III. CONCLUSION

      For the reasons stated above, the government’s motion to dismiss the claim of
Walter A. Bates and Sandra J. Bates for lack of subject-matter jurisdiction is
GRANTED. The Clerk shall dismiss the claim of Mr. and Mrs. Bates from this
lawsuit.




refund request, see Bates, 
2015 WL 7444285
, at *4, it did not explain whether it was
treating United as the filer of a 2003 FICA return and using the three-year period
under 26 U.S.C. § 6511, or treating Mr. and Mrs. Bates as non-filers and employing
the two-year period dating from payment of the taxes.

7 Because the Court has found jurisdiction to be lacking, the alternative ground for
dismissal is moot and need not be addressed.
                                         -7-
IT IS SO ORDERED.




                    -8-