David De Csepel v. Republic of Hungary

United States Court of Appeals

FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued September 8, 2025 Decided January 23, 2026

No. 24-7045

DAVID L. DE CSEPEL, ET AL.,

APPELLANTS

v.

REPUBLIC OF HUNGARY, A FOREIGN STATE, ET AL.,

APPELLEES

Appeal from the United States District Court

for the District of Columbia

(No. 1:10-cv-01261)

Alycia Regan Benenati argued the cause for appellants.

With her on the briefs were Sheron Korpus and David E. Mills.

Aaron M. Brian argued the cause for appellees. With him

on the brief were Thaddeus J. Stauber and Zachary C. Osinski.

Adam R. Tarosky entered an appearance.

2

No. 24-7148

DAVID L. DE CSEPEL, ET AL.,

APPELLANTS

v.

REPUBLIC OF HUNGARY, A FOREIGN STATE, ET AL.,

APPELLEES

Appeal from the United States District Court

for the District of Columbia

(No. 1:10-cv-01261)

Alycia Regan Benenati argued the cause for appellants.

With her on the briefs was Sheron Korpus. David E. Mills

entered an appearance.

Aaron M. Brian argued the cause for appellees. With him

on the brief were Thaddeus J. Stauber and Zachary C. Osinski.

Adam R. Tarosky entered an appearance.

Before: PILLARD and PAN, Circuit Judges, and ROGERS,

Senior Circuit Judge.

Opinion for the Court filed by Circuit Judge PILLARD.

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PILLARD, Circuit Judge: These related appeals call on us

to consider, for the fourth time, a family’s decades-long effort

to recover artwork that the Hungarian government and its Nazi

collaborators seized from it during and following World War

II. The historical context for this dispute is the campaign of

annihilation unleashed on Hungary’s Jews following that

country’s occupation by Nazi Germany in 1944, mere months

before the end of the war in Europe. In less than a year, more

than two-thirds of Hungary’s prewar Jewish population was

murdered, most of them at Auschwitz, in what Winston

Churchill described as “one of the greatest and most horrible

crimes ever committed.” Jewish property, meanwhile, was

seized by Hungarian and German authorities and redistributed

across Europe—the spoils of a regime of state-perpetrated

genocide.

This litigation is one of many suits brought by descendants

of the victims of the Hungarian Holocaust seeking to recover

their seized property. The narrow legal question we confront

in these appeals is whether claims regarding any of the stolen

artwork at issue are actionable in U.S. courts under the Foreign

Sovereign Immunities Act’s expropriation exception. Our

circuit has grappled with aspects of that question since the

outset of this suit fifteen years ago, and the intervening

doctrinal clarifications have proved challenging for the

family’s claims. On remand from our third decision in this

case, the district court, in two related decisions, dismissed this

case entirely. Separate judgments generated two appeals,

which we consolidated here for oral argument and decision.

For the reasons explained below, we hold that U.S. courts

lack jurisdiction over the family’s claims. Plaintiffs have the

burden to establish that their artwork was taken in violation of

the international law of expropriation. They have not done so.

No international authorities of which we have been made aware

4

support plaintiffs’ assertions that a nation-state’s taking of

property either from a foreign national during a wartime

military occupation or from a de facto stateless person violates

the international law of expropriation as it stood when the FSIA

was enacted. And, as to two paintings that the family recovered

after the war but that Hungary retook in the postwar period, the

domestic-takings rule and a preexisting treaty prevent us from

exercising jurisdiction. We therefore affirm the judgments of

the district court.

I.

A.

The Foreign Sovereign Immunities Act (FSIA) provides

‘‘the sole basis for obtaining jurisdiction over a foreign state in

our courts.’’ Argentine Republic v. Amerada Hess Shipping

Corp., 488 U.S. 428, 434 (1989); see 28 U.S.C. § 1602 et seq.

Absent a preexisting agreement between the United States and

a foreign state, the FSIA precludes jurisdiction over suits

against a foreign state—or its agents or instrumentalities—

unless an exception applies. Republic of Hungary v. Simon

(Simon IV), 604 U.S. 115, 118 (2025); see 28 U.S.C. §§ 1604,

1605-1605B, 1607. At issue in this case is the FSIA’s

expropriation exception. That exception waives a foreign

state’s sovereign immunity in any case in which:

[1] rights in property taken in violation of

international law are in issue and [2.A.] that property

or any property exchanged for such property is

present in the United States in connection with a

commercial activity carried on in the United States by

the foreign state; or [2.B.] that property or any

property exchanged for such property is owned or

operated by an agency or instrumentality of the

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foreign state and that agency or instrumentality is

engaged in a commercial activity in the United States.

28 U.S.C. § 1605(a)(3). The exception thus “has two

requirements.” de Csepel v. Republic of Hungary (de Csepel

IV), 859 F.3d 1094, 1101 (D.C. Cir. 2017). “A claim satisfies

the exception if (1) ‘rights in property taken in violation of

international law are in issue,’ and (2) there is an adequate

commercial nexus between the United States and the

defendants.” Id. All agree—and the record reflects—that the

property at issue (the family’s artwork) is owned by agencies

or instrumentalities of Hungary that are sufficiently engaged in

commercial activity in the United States. Id. at 1104. So only

the requirement that defendants have committed a “tak[ing] in

violation of international law” is at issue in these appeals.

With respect to whether the FSIA covers the type of

takings at issue here, the Supreme Court has held that “the

phrase ‘rights in property taken in violation of international

law,’ as used in the FSIA’s expropriation exception, refers to

violations of the international law of expropriation.” Federal

Republic of Germany v. Philipp, 592 U.S. 169, 187 (2021).

Plaintiffs invoking that exception must therefore identify a

violation of the international law of expropriation specifically

and cannot rest on contravention of other bodies of

international law, such as international human rights law. Id.

at 182. The international law of expropriation referenced in

section 1605(a)(3) “incorporates the domestic takings rule,”

under which a foreign sovereign’s taking of its own nationals’

property does not implicate the international legal system. Id.

at 176-80, 187. As a result, Philipp generally bars plaintiffs

who were nationals of the expropriating state at the time of the

alleged taking from invoking the FSIA’s expropriation

exception to establish jurisdiction in U.S. courts. See, e.g.,

Ivanenko v. Yanukovich, 995 F.3d 232, 237 (D.C. Cir. 2021).

6

In addition to exceptions the statute separately enumerates,

28 U.S.C. §§ 1605-1607, FSIA immunity is “[s]ubject to

existing international agreements to which the United States is

a party at the time of [the FSIA’s] enactment,” id. § 1604.

Thus, “if there is a conflict between the FSIA and such an

agreement regarding the availability of a judicial remedy

against a contracting state, the agreement prevails.” de Csepel

v. Republic of Hungary (de Csepel II), 714 F.3d 591, 601 (D.C.

Cir. 2013) (formatting modified). For a treaty to bar

jurisdiction otherwise available under the FSIA, the claims for

which jurisdiction is invoked must fall expressly within the

treaty’s scope. See id.

B.

We described the historical background of this case in

earlier opinions. See de Csepel II, 714 F.3d at 594-96; de

Csepel IV, 859 F.3d at 1097-98; de Csepel v. Republic of

Hungary (de Csepel VI), 27 F.4th 736, 739-41 (D.C. Cir. 2022).

For the convenience of the reader, we do so again here,

highlighting the most relevant context.

Baron Mór Lipót Herzog was a “passionate Jewish art

collector in pre-war Hungary” who had assembled before the

war a collection of more than two thousand paintings,

sculptures, and other artworks. Am. Compl. ¶ 37 (24-7045 J.A.

301).1 Known as the “Herzog Collection,” that body of artwork

was “one of Europe’s great private collections of art, and the

largest in Hungary,” and included works by renowned artists

such as El Greco, Velázquez, Renoir, and Monet. Id.

Following Herzog’s death in 1934 and his wife’s shortly

1

References to the appropriate brief or joint appendix are

preceded by the relevant case number.

7

thereafter, their daughter Erzsébet and two sons István and

András inherited the collection.

Then came World War II and Hungary’s alliance with the

Axis Powers under Nazi leadership. During the war, Hungary

intensified a program of Jewish persecution that had

commenced in earnest in the late 1930s. It restricted Jewish

employment, prohibited sexual relations between Jews and

non-Jews, pressed some Jews into forced labor, and exiled

others to territories under German control. Nonetheless,

Hungary’s Jews “were treated significantly better in

comparison to [Jews in] other parts of Nazi-controlled Europe”

and consequently became “firmly convinced that they would

survive the war under the continued protection” of the

Hungarian state. Kende Decl. ¶¶ 13, 15 (24-7045 J.A. 2373-

74) (internal quotation marks omitted). That all changed in

early 1944, “on the very eve of triumph over the barbarism

which their persecution symbolize[d].” Franklin D. Roosevelt,

Statement on Opening Frontiers to War Victims and Justice for

War Crimes, The American Presidency Project (Mar. 24,

1944). Frustrated by Hungary’s “lack of vigor” in persecuting

its Jewish population and fearing that the country would defect

in the final days of the war from its alliance with Germany,

Adolf Hitler sent German troops to occupy the country in

March of that year. Kende Decl. ¶ 17 (24-7045 J.A. 2374)

(internal quotation marks omitted). Commander Adolf

Eichmann of the German paramilitary force Schutzstaffel, or

SS, entered the country along with the occupying forces and

established headquarters at the Majestic Hotel in Budapest.

The occupiers established a pro-Nazi puppet government

under Hungarian prime minister Döme Sztójay, who acted

under German orders to “solv[e] the Jewish question and

supply[] Germany with desperately needed goods.” Id. ¶ 22

(J.A. 2376) (internal quotation marks omitted).

8

The arrival of the Germans marked a sharp deterioration

in the position of Hungary’s Jews. Indeed, “[n]owhere was the

Holocaust executed with such speed and ferocity as it was in

Hungary.” Simon v. Republic of Hungary (Simon I), 812 F.3d

127, 133 (D.C. Cir. 2016). Between mid-May and mid-July

1944, Hungarian authorities deported over fifty percent of the

country’s Jewish population. By war’s end, most were dead,

ninety percent of them having been “murdered upon arrival” at

Auschwitz and other death camps. Simon v. Republic of

Hungary (Simon II), 911 F.3d 1172, 1175 (D.C. Cir. 2018). As

an integral part of its genocidal program, “[t]he Hungarian

government, including the Hungarian state police, authorized,

fully supported and carried out a program of wholesale plunder

of Jewish property, stripping anyone ‘of Jewish origin’ of their

assets.” Am. Compl. ¶ 53 (24-7045 J.A. 305). Jews “were

required to register all of their property and valuables” above a

certain value, and the Hungarian government “inventoried the

contents of safes and confiscated cash, jewelry, and other

valuables belonging to Jews.” Id. ¶ 54 (24-7045 J.A. 305).

“[P]articularly concerned with the retention of artistic treasures

belonging to Jews,” the Hungarian government established “a

so-called Commission for the Recording and Safeguarding of

Impounded Art Objects of Jews . . . and required Hungarian

Jews promptly to register all art objects in their possession.”

Id. ¶ 55 (24-7045 J.A. 305). “These art treasures were

sequestered and collected centrally by the Commission for Art

Objects,” headed by the director of the Hungarian Museum of

Fine Arts. Id.

Faced with widespread looting of Jewish property, the

Herzogs “attempted to save their art works from damage and

confiscation by hiding the bulk of [them] in the cellar of one of

the family’s factories at Budafok.” Id. ¶ 57 (24-7045 J.A. 306).

Despite the family’s efforts, “the Hungarian government and

their Nazi[] collaborators discovered the hiding place” and

9

confiscated the artworks. Id. ¶ 58 (24-7045 J.A. 306). The

collection was “taken directly to Adolf Eichmann’s

headquarters at the Majestic Hotel in Budapest for his

inspection,” where he “selected many of the best pieces” for

display near Gestapo headquarters and for eventual transport to

Germany. Id. ¶ 59 (24-7045 J.A. 306). “The remainder was

handed over by the Hungarian government to [its] Museum of

Fine Arts for safekeeping.” Id. After the seizure of the

collection, a pro-Nazi newspaper ran an article in which the

director of the Hungarian Museum of Fine Arts boasted that the

“Herzog collection contains treasures the artistic value of

which exceeds that of any similar collection in the

country. . . . If the state now takes over these treasures, the

Museum of Fine Arts will become a collection ranking just

behind Madrid.” Id. ¶ 58 (24-7045 J.A. 306).

“Fearing for their lives, and stripped of their property and

livelihoods, the Herzog family was forced to flee Hungary or

face extermination.” Id. ¶ 62 (24-7045 J.A. 307). Erzsébet

Herzog (Erzsébet Weiss de Csepel following her marriage) fled

Hungary with her children, first reaching Portugal and

eventually settling in the United States, where she became a

citizen in 1952. István Herzog was nearly sent to Auschwitz

but “escaped after his former sister-in-law’s

husband . . . arranged for him to be put in a safe house under

the protection of the Spanish Embassy.” Id. ¶ 41 (24-7045 J.A.

302). “He died in 1966, leaving his estate to his two sons,

Stephan and Péter Herzog, and his second wife, Mária

Bertalanffy.” Id. András Herzog had been “sent . . . into

forced labor in 1942 and he died on the Eastern Front in 1943.”

Id. ¶ 40 (24-7045 J.A. 302). His daughters, Julia Alice Herzog

and Angela Maria Herzog, fled to Argentina and eventually

settled in Italy, where they now live.

10

The seized artworks were dispersed. Most were never

physically returned to the family. They instead were scattered

across Nazi-occupied Europe, shipped back to Hungary after

the war, and eventually deposited at the defendant institutions.

The artworks that were returned to the Herzog siblings or their

families in the years immediately following World War II were

soon taken back by the government for various reasons,

including a criminal-forfeiture judgment against István’s

former wife, Ilona Kiss. In 1973, the United States and

Hungary agreed to permanently settle the claims of U.S.

nationals regarding expropriations that had occurred as of the

date of the agreement. See Agreement Between the

Government of the United States of America and the

Government of the Hungarian People’s Republic Regarding

the Settlement of Claims, Hung.-U.S., Mar. 6, 1973, 24 U.S.T.

522 (1973 Agreement).

C.

After World War II, the Herzog family began a seven-

decade effort to reclaim their art collection. de Csepel IV, 859

F.3d at 1098. They first sued in the Hungarian courts. Id.

When those efforts proved unsuccessful, three heirs to the

collection—Erzsébet’s grandson David L. de Csepel, along

with András’s daughters Julia Alice and Angela Maria

Herzog—filed suit in 2010 in U.S. district court. Asserting

jurisdiction under the FSIA’s expropriation exception, 28

U.S.C. § 1605(a)(3), and commercial activity exception, id.

§ 1605(a)(2), they brought various common-law claims against

the Republic of Hungary, three art museums (the Budapest

Museum of Fine Arts, the Hungarian National Gallery, and the

Budapest Museum of Applied Arts), and the Budapest

University of Technology and Economics. They claimed

principally that defendants had “breached certain bailment

agreements entered into after World War II when they refused

11

to return pieces of the Herzog Collection upon demand in

2008.” de Csepel v. Republic of Hungary (de Csepel I), 808 F.

Supp. 2d 113, 120 (D.D.C. 2011). Plaintiffs alleged that, of the

forty-four pieces from the Herzog Collection originally at

issue, twenty-four were owned by the heirs of András, twelve

by the heirs of Erzsébet, and eight by the heirs of István. de

Csepel v. Republic of Hungary (de Csepel III), 169 F. Supp. 3d

143, 148 (D.D.C. 2016). Forty-two of those artworks were

originally seized during the Nazi occupation of Europe, while

two were taken during the Communist era. Id. The heirs

sought imposition of a constructive trust, an accounting,

disgorgement, a declaration of their ownership of the Herzog

Collection, and, ultimately, either return of the artwork or $100

million in compensation. Compl. pt. V (24-7045 J.A. 83-84).

On Hungary’s motion, the district court dismissed claims

regarding eleven pieces of artwork on grounds of international

comity, de Csepel I, 808 F. Supp. 2d at 144-45, but it sustained

jurisdiction over the remaining thirty-one under the FSIA’s

expropriation exception, id. at 133. The court reasoned that the

domestic-takings bar posed no barrier to suit because Hungary

had de facto stripped Hungarian Jews of their citizenship and

because German Nazi officials had been “active[ly]

involv[ed]” in the alleged takings. Id. at 129-30. On appeal,

we reversed the international-comity dismissal and otherwise

affirmed the district court on different grounds. See de Csepel

II, 714 F.3d at 594, 598. Because the complaint focused on

alleged repudiation of bailment agreements with the Hungarian

defendants, we held that, regardless of whether the

expropriation exception applied, the case fit “comfortably

within the FSIA’s commercial activity exception.” Id. at

598-601.

On remand, following discovery, the district court

concluded it could no longer sustain jurisdiction under the

12

commercial activity exception but reaffirmed that the

expropriation exception applied. de Csepel III, 169 F. Supp.

3d at 147. In doing so, it relied on our intervening decision in

Simon I, 812 F.3d 127, which had concluded that

expropriations from Jews during the Holocaust constituted

genocidal “takings” in violation of international law that are

actionable under the FSIA’s expropriation exception, id. at

142. See de Csepel III, 169 F. Supp. 3d at 163-64. As for the

two artworks that were first confiscated years after the

Holocaust, however, the district court held that it lacked

jurisdiction for fact-bound reasons not relevant to the current

appeal. Id. at 165-67.

We affirmed in part and reversed in part. See de Csepel

IV, 859 F.3d at 1097. In the main, we concluded that “[t]his

case is just like Simon [I],” id. at 1102, and thus the

expropriation exception was appropriate, id. at 1102-04. We

remanded to the district court for it to reconsider whether the

exception applied to the pieces of art returned to the Herzog

family after the war but later retaken by Hungary’s communist

government. Id. at 1104-05. Over a partial dissent by Judge

Randolph, we also dismissed the Republic of Hungary as a

defendant because we read the relevant clause of the

expropriation exception’s commercial-nexus requirement to

support jurisdiction over Hungary’s agencies or

instrumentalities but not the state itself. Id. at 1104-08. And

we granted the heirs leave to amend their complaint in light of

the Holocaust Expropriated Art Recovery Act of 2016 (HEAR

Act), Pub. L. No. 114-308, 130 Stat. 1524, which preempted

previous statutes of limitations and instituted a new six-year

statute of limitations from the passage of the Act for people

seeking recovery of Nazi-confiscated art. See de Csepel IV,

859 F.3d at 1109-10.

13

On remand, the heirs amended their complaint to reference

the HEAR Act and add previously time-barred conversion

claims for wartime takings of the artworks. See Am. Compl.

¶¶ 87-98, 109-117 (24-7045 J.A. 312-15, 316-18). The current

complaint also adds as a defendant the state-owned corporation

Hungarian National Asset Management, Inc. (MNV), which

owns and manages certain Hungarian assets, including the

artworks at issue in this case. Id. ¶¶ 3, 14 (24-7045 J.A. 286,

289).

Hungary responded with a third motion to dismiss. As

relevant here, the district court held that it had jurisdiction over

claims relating to just five of nineteen pieces of art that had

been returned to the Herzogs following the war, including the

two pieces that had been retaken by Hungary after their postwar

return: József’s Borsos’s Portrait of the Architect Mátyás

Zitterbarth (which belonged to András) and Mihály

Munkácsy’s In the Studio (which belonged to Erzsébet). See

de Csepel v. Republic of Hungary (de Csepel V), 613 F. Supp.

3d 255, 286-300 (D.D.C. 2020). The district court certified that

order for immediate appellate review under 28 U.S.C.

§ 1292(b), but we declined to exercise our discretion to review

“those fact-bound determinations” at that stage, limiting our

review to legal questions of broader import. de Csepel VI, 27

F.4th at 753. At the conclusion of that third appeal, therefore,

claims regarding sixteen of the original forty-four artworks in

the litigation had been dismissed (two in de Csepel III and

fourteen in de Csepel V), leaving twenty-eight pieces in play.

Meanwhile, the Supreme Court decided Philipp, which, as

noted, held that the FSIA’s expropriation exception

encompasses only takings in violation of the international law

of expropriation—not those contrary to international

human-rights law—and thus incorporates the domestic-takings

bar. See 592 U.S. at 187. In light of Philipp, Hungary moved

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to dismiss for want of FSIA jurisdiction over all “artworks that

Hungary took from its own citizens.” Mot. to Dismiss 1

(24-7045 J.A. 2062). According to defendants, that defect

barred the family’s claims to twenty-seven of the remaining

twenty-eight artworks—all but an early sixteenth-century

German sculpture called Figure of Santa Barbara, for which

there was “some evidence” that it was “seized by [non-

Hungarian] officials and removed from Hungary to a salt mine

in Bad Ischl, Austria.” Id. at 19 (24-7045 J.A. 2080).2

After briefing on the motion was complete, we decided

Simon v. Republic of Hungary (Simon III), 77 F.4th 1077 (D.C.

Cir. 2023), vacated on other grounds by Simon IV, 604 U.S.

115. In that case, we declined to exercise jurisdiction over an

expropriation claim against Hungary brought by plaintiffs who

had argued that the domestic-takings bar did not prevent suit

because their predecessors—also survivors of the Hungarian

Holocaust—had been rendered de facto stateless by the time of

the taking. Id. at 1097-98. The district court requested

2

There is no direct evidence of a wartime taking for three

artworks at issue: József Borsos’s Girls with Garlands of Flowers,

Mihály Munkácsy’s The Afternoon Visit, and Jewelry Bowl,

attributed to Sebastianus Hann. Mot. to Dismiss 18-19 (24-7045 J.A.

2079-80); 24-7045 Hungary Br. 14 & n.43. The heirs asserted

below, however, that “documentary evidence” “strongly supports the

conclusion that at least two of the artworks” were taken by Hungary

during the Nazi occupation. Opp. 35 (24-7045 J.A. 2272). They thus

argued that these pieces should be treated “in the same manner as the

other artworks that were part of the war-time takings,” id. at 37

(24-7045 J.A. 2274), a contention they renew on appeal, see 24-7045

Heirs’ Br. 16 & n.6. The district court appears to have done so, de

Csepel V, 613 F. Supp. 3d at 286-300, and defendants do not object

to that treatment. We therefore treat these artworks as wartime

takings.

15

supplemental briefing on the impact of our Simon III decision

on plaintiffs’ claims.

In the opinion under review in No. 24-7045, the district

court granted Hungary’s motion to dismiss as to twenty-seven

artworks—twenty-five that Hungary took during the

Holocaust, and two (In the Studio and Portrait of the Architect)

that Hungary retook later. de Csepel v. Republic of Hungary

(de Csepel VII), 695 F. Supp. 3d 1, 28, 34, 37 (D.D.C. 2023).

It first rejected the heirs’ attempt to evade the domestic-takings

bar by arguing that Germany was actually responsible for the

expropriations. The district court held instead that Germany’s

occupation was not alone enough to render it responsible and

that the record did not otherwise show that Germany directed

or coerced the takings. Id. at 10-28. The court then held that,

as in Simon III, the plaintiffs had not shown that a state’s taking

of a de facto stateless person’s property violates the

international law of expropriation. Id. at 29-34. Finally, the

court accepted the defendants’ urging that it reconsider

jurisdiction over In the Studio and Portrait of the Architect,

concluding on the available evidence that neither piece fell

under the expropriation exception. Id. at 34-38. As for the

Santa Barbara—which evidence indicated German officers

had taken—the court instructed the parties to file additional

briefing. Id. at 38.

In the opinion under review in No. 24-7148, the district

court held that it could not exercise jurisdiction over the Santa

Barbara because “at the time of the FSIA’s enactment, the

international law of expropriation did not include takings in

violation of the international laws of war.” de Csepel v.

Republic of Hungary (de Csepel VIII), 752 F. Supp. 3d 147,

160 (D.D.C. 2024). The Santa Barbara “was taken, according

to plaintiffs, by Nazi officials during Germany’s wartime

occupation of Hungary,” making it a wartime taking for which

16

the heirs could not establish jurisdiction under the

expropriation exception. Id. at 162. The court held, in the

alternative, that based on forum non conveniens it would not

exercise jurisdiction over the Santa Barbara because the

parties agreed that an adequate alternative forum was available

in Hungary, and the relevant private- and public-interest factors

favored litigation there given that the remaining plaintiffs were

not American citizens. Id. at 162-64.

Plaintiffs timely appealed both decisions.

II.

We review the district court’s jurisdictional rulings on

questions of law de novo, Yanukovich, 995 F.3d at 236, and its

factual determinations for clear error, Price v. Socialist

People’s Libyan Arab Jamahiriya, 389 F.3d 192, 197 (D.C.

Cir. 2004).

A plaintiff seeking to sue a foreign sovereign under the

FSIA “bears the ‘initial burden’ of overcoming the Act’s

‘presumption of immunity’ by making out a legally sufficient

case that an exception does apply in the first place.” Helmerich

& Payne Int’l Drilling Co. v. Bolivarian Republic of Venezuela,

743 F. App’x 442, 449 (D.C. Cir. 2018) (quoting Bell

Helicopter Textron, Inc. v. Islamic Republic of Iran, 734 F.3d

1175, 1183 (D.C. Cir. 2013)). To do so under the expropriation

exception, a plaintiff must advance a “valid claim that

‘property’ has been ‘taken in violation of international law.’ A

nonfrivolous argument to that effect is insufficient.”

Bolivarian Republic of Venezuela v. Helmerich & Payne Int’l

Drilling Co., 581 U.S. 170, 178 (2017) (internal citation

omitted). Once a plaintiff has adequately shown that the

exception applies, “the burden shifts to [the foreign sovereign

defendant] to disprove that claim.” Helmerich, 743 F. App’x

at 449.

17

If a defendant challenges “the factual basis of the court’s

jurisdiction,” the court “must go beyond the pleadings and

resolve any disputed issues of fact” necessary to adjudicate the

motion. Phoenix Consulting, Inc. v. Republic of Angola, 216

F.3d 36, 40 (D.C. Cir. 2000). In such a case, “the plaintiffs will

bear the burden of production, and the defendants will bear the

burden of persuasion to establish the absence of the factual

basis by a preponderance of the evidence.” Simon I, 812 F.3d

at 147 (internal quotation marks omitted).

III.

We begin by considering whether we have jurisdiction

over the claim for the Santa Barbara, as our resolution of that

issue affects treatment of the others. Before we address the

parties’ legal contentions, two preliminary disputes bear

mention. First, despite having previously acknowledged that

“some evidence” suggested that the Santa Barbara had been

taken by “non-Hungarian forces,” Mot. to Dismiss 19 (24-7045

J.A. 2080), Hungary now asserts that the heirs have not met

their factual burden on that score, see 24-7148 Hungary Br.

27-29. We disagree. The heirs have met their burden by

producing evidence that non-Hungarian officials took that

sculpture. See de Csepel VIII, 752 F. Supp. 3d at 158. For its

part, Hungary points to no evidence—much less a

preponderance—showing otherwise. Cf. Simon I, 812 F.3d at

147. It has failed to “disprove” the heirs’ proffered factual

basis for the assertion of jurisdiction. Helmerich, 743 F. App’x

at 449.

Second, Hungary renews its argument that the heirs should

be estopped from relying on their forebears’ de jure Hungarian

nationality to avoid the domestic-takings bar for Germany’s

taking of the Santa Barbara because the heirs elsewhere have

maintained that those relatives were rendered de facto stateless

18

by the Holocaust. See 24-7148 Hungary Br. 24-26 & nn.5-6.

Courts have no occasion to apply the discretionary doctrine of

judicial estoppel absent a “clear[] inconsisten[cy]” between a

party’s earlier and later positions. Temple Univ. Hosp., Inc. v.

NLRB, 929 F.3d 729, 733 (D.C. Cir. 2019). As the very terms

“de facto” and “de jure” indicate, there is at least a formal—

and potentially legal—distinction between citizens who have

been officially denationalized and those who have simply been

treated as such. The heirs’ arguments from their forebears’ de

facto statelessness take as a premise that the Herzogs remained

de jure citizens of Hungary—the very same premise

undergirding their jurisdictional arguments as to the Santa

Barbara. We therefore conclude that the district court did not

abuse its discretion in declining to estop the heirs from relying

on their forebears’ de jure Hungarian nationality.

To determine whether the expropriation exception confers

jurisdiction here over plaintiffs’ claims regarding the Santa

Barbara, we “look to the law of property.” Philipp, 592 U.S.

at 180. The heirs rest their case on section 185 of the Second

Restatement of Foreign Relations Law, which lists three

independent conditions under which the “taking by a state of

property of an alien is wrongful” according to international

property law: lack of public purpose, discrimination with

respect to nationality, or absence of just compensation.

Restatement (Second) of Foreign Relations Law § 185 (A.L.I.

1965) (Second Restatement). According to plaintiffs,

Germany’s plunder of the Santa Barbara was an

“uncompensated, discriminatory taking of a foreign national’s

property” and thus squarely implicated one or more of the

conditions rendering an international taking wrongful.

24-7148 Heirs’ Br. 20.

As the operative Restatement at the time of the FSIA’s

enactment, the Second Restatement “bears authoritative weight

19

in interpreting the Act.” Simon III, 77 F.4th at 1097; see

Philipp, 592 U.S. at 180. Here, however, it cannot satisfy the

heirs’ burden. As the district court observed, the Second

Restatement expressly limits the applicability of its

commentary to “times of peace,” and it states more than once

that “[t]he effect of war or hostilities . . . is beyond the scope of

the Restatement of this Subject.” Second Restatement pt. IV,

Intro. Notes ¶ 1; see id. § 34, Reporters’ Note 2. Plaintiffs do

not dispute—indeed, they assert—that the Santa Barbara was

taken by Germany during its wartime military occupation of

Hungary. See 24-7148 Heirs’ Br. 9; Oral Arg. Rec. 0:52-1:07,

6:25-53. That sculpture’s taking is therefore “beyond the

scope” of the very Restatement on which the heirs rely to meet

their burden of presenting a “valid claim” that the expropriation

exception applies. Helmerich, 581 U.S. at 178.

In response, plaintiffs insist that “a taking can[] violate

both the international law of war and the international law of

expropriation.” 24-7148 Heirs’ Br. 24; see 24-7148 Reply Br.

3-13. Even if that is theoretically true, parties must show that

the challenged taking violated the international law of

expropriation as such, regardless of whether it also violated

some other body of law. On that question, the heirs’ reliance

on the Second Restatement leaves them empty handed. Pressed

at oral argument for some source of international law that might

support their argument, plaintiffs mentioned only the Hague

Convention—itself a codification of the laws of war, not the

international law of property. Oral Arg. Rec. 17:47-18:53,

20:16-21:43. A cursory comparison of the two bodies of law,

moreover, places in doubt their suggestion that “the same

principles apply to the war-time taking of property belonging

to aliens” as to peacetime expropriations. 24-7148 Heirs’ Br.

22. The Second Restatement permits expropriations during

peacetime as long as none of the conditions in section 185 is

violated, see Second Restatement § 185, whereas the Hague

20

Convention states flatly that “[p]illage is forbidden” and

“[p]rivate property cannot be confiscated” during military

occupations, Hague Convention No. IV Respecting the Laws

and Customs of War on Land, arts. 43, 46-47, Oct. 18, 1907,

36 Stat. 2277. And even putting aside those incongruities, we

could not exercise jurisdiction under the FSIA on the mere

supposition that the principles articulated by the Second

Restatement might apply to wartime situations, despite its

explicit disclaimer that they may not.

Without any source establishing a violation of the

international law of expropriation, plaintiffs point to U.S.

judicial decisions that they assert have resolved this question in

their favor. If anything, however, the cases show only that this

issue has yet to be squarely decided by any court. The Supreme

Court in Philipp stated in dicta that “[c]laims concerning Nazi-

era art takings could be brought under the expropriation

exception where the claims involve the taking of a foreign

national’s property.” 592 U.S. at 185. But that case concerned

a 1935 forced art sale in prewar Nazi Germany, so the Court

had no occasion to consider the narrower question of wartime

Nazi takings. See id. at 174. The heirs point out that Philipp

cited the Supreme Court’s earlier decision in Republic of

Austria v. Altmann, 541 U.S. 677 (2004), which concerned a

suit brought under the expropriation exception to recover art

that Austria had taken from a Czechoslovakian national, see id.

at 680-82. Altmann, however, concerned only whether the

FSIA applies to pre-enactment conduct, see id. at 681, not

whether wartime takings establish jurisdiction under the

expropriation exception. And while Nazi Germany had

originally confiscated that art during its annexation of Austria,

the Court was clear that the basis for the expropriation claim—

and the locus of the Court’s review—was Austria’s postwar

conduct thwarting the claimant’s attempts to reassert

ownership of the art, not “the legal validity of title passed

21

through Nazi looting.” Id. at 706 (Breyer, J., concurring); see

id. at 683-87, 697 (majority opinion). Neither Altmann nor

Philipp, therefore, counsels us to accept the heirs’ theory of

jurisdiction.

Nor do any other authorities brought to our attention

support our jurisdiction. The Supreme Court in Altmann

reviewed only part of the Ninth Circuit’s decision, leaving

undisturbed the determination that the expropriation exception

applied to the Nazi-era taking. See Altmann v. Republic of

Austria, 317 F.3d 954, 968 (9th Cir. 2002). But no party there

asserted that the international law of expropriation is

inapplicable to wartime takings, so the Ninth Circuit had no

occasion to consider the point. See, e.g., id. (relying on non-

wartime precedent invoking the Second Restatement).

Plaintiffs also point to a case from our district court that

similarly held that challenges to Nazi wartime takings may

proceed under the expropriation exception. See Agudas

Chasidei Chabad of U.S. v. Russian Federation, 466 F. Supp.

2d 6, 19-20 (D.D.C. 2006). That case relied on other district

courts’ identification of principles of international law. See id.

(citing Altmann v. Republic of Austria, 142 F. Supp. 2d 1187

(C.D. Cal. 2001), and Bodner v. Banque Paribas, 114 F. Supp.

2d 117 (E.D.N.Y. 2000)). Like Agudas Chasidei itself, see id.

at 15-16, those cases invoked either the Restatement’s

approach to non-wartime takings, see Altmann, 142 F. Supp.

2d at 1202—which we have already explained does not support

the heirs’ position on wartime takings—or the international law

of war, see Bodner, 114 F. Supp. 2d at 134, an approach that

Philipp has since abrogated. In any event, we did not review

that holding on appeal, see Agudas Chasidei Chabad of U.S. v.

Russian Federation, 528 F.3d 934, 943 (D.C. Cir. 2008), so any

contrary conclusion does not bind us. And Cassirer v.

Kingdom of Spain, 616 F.3d 1019 (9th Cir. 2010) (en banc),

concerned only Germany’s pre-war confiscation of artwork

22

from plaintiffs’ de jure stateless Jewish forebears, see id. at

1023 & n.2; Cassirer v. Kingdom of Spain, 461 F. Supp. 2d

1157, 1165-66 (C.D. Cal. 2006); Compl. ¶¶ 21-24, Cassirer v.

Kingdom of Spain, No. 05-3459 (C.D. Cal. May 10, 2005),

ECF No. 1 (alleging that the taking occurred in 1939 shortly

before the war began).

Finally, the heirs point to a 1949 State Department press

release and various Holocaust-related statutes in support of

their general contention that “the United States has long

recognized the invalidity of Nazi war time seizures of

property.” 24-7148 Heirs’ Br. 26-29. Each of those statutes,

however, was raised in Philipp, where the Court held that they

“do not speak to sovereign immunity.” 592 U.S. at 186. And

a State Department letter, however indicative of the stance of

the Executive at the time, does not control the jurisdiction of

the federal courts—especially when that letter addressed a case

involving only the act-of-state doctrine and did not mention

foreign sovereign immunity. See Bernstein v. N. V.

Nederlandsche-Amerikaansche, Stoomvaart-Maatschappij,

210 F.2d 375, 375-76 (2d Cir. 1954); see also First Nat’l City

Bank v. Banco Nacional de Cuba, 406 U.S. 759, 764 (1972)

(plurality opinion) (referring to the “so-called Bernstein

exception to the act of state doctrine”). The heirs, in short, must

establish that Congress in the FSIA has authorized federal

courts to exercise jurisdiction in circumstances like these,

which requires showing that the international law of

expropriation reaches them. It is not enough that postwar U.S.

policy generally favored restitution for Nazi-era takings.

In holding that the FSIA’s expropriation exception

incorporates “the international law governing property rights”

as such, the Supreme Court approvingly quoted the

International Court of Justice, which declared that “a State is

not deprived of immunity by reason of the fact that it is accused

23

of serious violations of international human rights law or the

international law of armed conflict.” Jurisdictional Immunities

of the State (Germany v. Italy), Judgment, 2012 I.C.J. 99, ¶ 91

(Feb. 3); see Philipp, 592 U.S. at 182. The Supreme Court read

the expropriation exception more narrowly than we and other

lower courts had done, expressly warning against

“transforming the expropriation exception into an all-purpose

jurisdictional hook for adjudicating human rights violations.”

Philipp, 592 U.S. at 183.

We heed that directive here. Because we conclude that the

heirs have not met their burden, we need not decide whether

the FSIA’s expropriation exception ever establishes

jurisdiction over claims of wartime property confiscation. It

suffices that the authorities the heirs have presented to the court

do not make out a “valid claim,” Helmerich, 581 U.S. at 178,

that wartime takings violate the international law of

expropriation. The FSIA’s expropriation exception thus does

not support jurisdiction over plaintiffs’ claims relating to the

Santa Barbara.

IV.

A.

The foregoing obviates the need to adjudicate the heirs’

theory that Germany, as the occupying power at the time, is

legally responsible for all wartime takings of the Herzog

Collection, including the twenty-five works for which the

available evidence points only to Hungarian involvement. See

24-7045 Heirs’ Br. 38-52; de Csepel VII, 695 F. Supp. 3d at

10-28. Plaintiffs press several versions of that theory on

appeal, each of which asks us to avoid the domestic-takings bar

by looking beyond the Hungarian actors to attribute

responsibility for the takings to Germany. 24-7045 Heirs’ Br.

24

42-43. That analytic step leads to a dead end. To the extent

the heirs succeed on any of their theories of German

responsibility, those artworks would then be in the same

position as the Santa Barbara sculpture vis-à-vis the wartime-

takings question—as plaintiffs themselves admitted at oral

argument. See Oral Arg. Rec. 10:34-12:00. It would thus make

little difference whether plaintiffs could show that Germany

was legally responsible for the takings of artworks other than

the Santa Barbara. Even assuming that it was, the heirs would

run up against the same inability to make out a legally sufficient

case that wartime takings fall within the ambit of the

expropriation exception. See 24-7045 Hungary Br. 37.

We resolve plaintiffs’ German-responsibility theories on

this basis even though it was not a ground for dismissal that

Hungary pressed before the district court for these artworks.

“[W]hen an issue or claim is properly before the court, the court

is not limited to the particular legal theories advanced by the

parties, but rather retains the independent power to identify and

apply the proper construction of governing law.” U.S. Nat.

Bank of Ore. v. Indep. Ins. Agents of Am., Inc., 508 U.S. 439,

446 (1993). These appeals arise from the same case between

the same parties. The wartime-takings question was

extensively litigated before the district court in the related

appeal concerning the Santa Barbara. And, to the extent

Germany is ultimately responsible for the takings, all the art in

question is positioned the same with regard to the relevant legal

question. We therefore do not confront a scenario in which

“[e]normous confusion . . . would result” by permitting

counsel “to appeal upon points not presented to the court

below.” Keepseagle v. Perdue, 856 F.3d 1039, 1053-54 (D.C.

Cir. 2017) (internal quotation marks omitted). We see no point

in untangling the thicket of state responsibility for takings

during a military occupation when a deeper jurisdictional

defect bars the claim either way.

25

B.

That leaves only the heirs’ alternative theory in support of

jurisdiction, premised on the asserted de facto statelessness of

the Herzogs when Hungary took their property. In Simon III,

we addressed a question left open by Philipp: whether

descendants of individuals who were rendered de facto

stateless by the Holocaust can evade the domestic-takings bar

on the theory that their forebears should be considered “aliens”

for the purposes of the international law of expropriation. 77

F.4th at 1094-98. We held that Philipp might accommodate

such a theory, see id. at 1094-96, but we nonetheless concluded

that the plaintiffs had not demonstrated that such a theory had

“jelled into a binding rule of customary international law,” id.

at 1098. The Simon III plaintiffs had relied on the fact that the

term “alien” in the Second Restatement denotes both foreign

nationals and stateless persons “for purposes of the

responsibility of a state for injury” to an individual, Second

Restatement § 171, thus seeming to encompass stateless

persons within international expropriations law. But, we noted,

the Second Restatement also provides that stateless aliens are

“without remedy” under international law for takings claims

against an expropriating state, with certain exceptions not

relevant to the case. Simon III, 77 F.4th at 1097-98 (quoting

Second Restatement § 175 cmt. d). And we found no support

in the plaintiffs’ secondary sources for the contention that the

taking of a de facto stateless person’s property is otherwise a

remediable violation of the international law of expropriation.

See id. at 1098.

The heirs aim to pick up where the Simon III plaintiffs left

off. Rather than identify new “sources of international law not

before us” in that case, id., they also rely on the Second

Restatement and instead argue that neither it nor the FSIA

“mandates that the injured party have a particular international

26

law remedy available at the time of the taking in order for the

conduct at issue to be wrongful and constitute a violation of

international law.” 24-7045 Heirs’ Br. 34. We may assume,

like the district court, that Hungary’s persecution of the

Herzogs indeed rendered them de facto stateless, see de Csepel

VII, 695 F. Supp. 3d at 31; 24-7045 Heirs’ Br. 29; see also

Simon III, 77 F.4th at 1097 (taking this approach), and proceed

to examine whether that fact would enable plaintiffs to

establish jurisdiction.

Even if plaintiffs’ interpretation of the Second

Restatement is correct, their exclusive reliance on it

nonetheless leaves them shorthanded once again. For one, they

fail to show that the Second Restatement refers to de facto,

rather than only de jure, stateless persons. As the district court

explained and Hungary argues here, if the Second Restatement

refers only to persons officially denaturalized, then it provides

no support for the contention that de facto stateless persons

constitute a distinct category of alien protected by international

law. See de Csepel VII, 695 F. Supp. 3d at 33 n.20; 24-7045

Hungary Br. 38-39. In the absence of authority for distinct

international-law protection as de facto stateless, plaintiffs

retain their de jure Hungarian nationality so presumably would

be subject to the domestic-takings bar. Plaintiffs never address

this lacuna in their argument, instead relying on a district court

case involving only de jure denationalization. See 24-7045

Heirs’ Br. 37 (citing Ambar v. Federal Republic of Germany,

596 F. Supp. 3d 76, 84 (D.D.C. 2022)). The Second

Restatement, ambiguous on this point, does not support the

conclusion that the heirs’ position had “crystallized into an

international norm that bears the heft of customary law.”

Helmerich, 743 F. App’x at 449.

Assuming, moreover, that the Second Restatement could

plausibly be interpreted to refer to de facto stateless persons,

27

“its pronouncements are useful only if they flow from sources

of positive law such as judicial authority or reasoned scholarly

commentary.” Id. at 453. Plaintiffs point to no source of

international law supporting their interpretation of the Second

Restatement. Conversely, many such sources posit that the

opposite rule flows from the fact that international law treats a

state’s injury to an alien as, ordinarily, an injury to the alien’s

state rather than to the alien herself. See Philipp, 592 U.S. at

176-77; Mezerhane v. Republica Bolivariana de Venezuela,

785 F.3d 545, 551 (11th Cir. 2015) (agreeing with Fifth Circuit

that “injuries to individuals have been cognizable only where

they implicate two or more different nations” (formatting

altered)). That conceptualization poses a difficult problem for

those who, like plaintiffs, would premise a violation of

international law on their forebears’ statelessness.

Early in the last century, renowned international-law

theorist L.F.L. Oppenheim reported that “stateless

individuals . . . lack any protection whatever as far as”

international law is concerned because, by dint of having no

nationality, “the link by which they could derive benefits from”

that law “is missing.” 1 Oppenheim, International Law: A

Treatise § 312 (2d ed. 1912). Thus, “as a point of international

legality there is no restriction whatever upon a State’s

maltreating them to any extent.” Id. His 1955 update to that

treatise restated that basic principle, while noting the important

exception of human-rights law. Id. (8th ed. 1955). So, too, a

seminal 1931 claims-commission arbitral decision observed

that a state “does not commit an international delinquency in

inflicting an injury upon an individual lacking nationality.”

Dickson Car Wheel Co. (U.S.A.) v. United Mexican States, 4

R.I.A.A. 669, 678 (Mex.-U.S. Gen. Claim Comm’n, July

1931). And modern scholars have written that, “in general,

stateless persons cannot be classified as or treated like aliens.”

Kay Hailbronner & Jana Gogolin, Aliens, Max Planck

28

Encyclopedias of International Law, ¶ 3 (July 2013). As one

commentator puts it, the “substantive guarantees of the law of

aliens developed hand-in-hand with the exercise of diplomatic

protection, which, at least from a historical perspective,

referred only to nationals of other states.” Sebastián Mantilla

Blanco, Full Protection and Security in International

Investment Law 172 (2019).

Tellingly, the Third Restatement of Foreign Relations Law

entirely abandons the language on statelessness in its

predecessor Restatement that provided a potential opening for

plaintiffs. The Third Restatement clarifies that the

international law of expropriation protects only “a national of

another state” or a “foreign national,” Restatement (Third) of

Foreign Relations Law, § 712 & cmt. a (1987), and “provide[s]

no protection for persons who have no nationality,” id. § 713

cmt. d. Instead, it notes, such persons are covered by “general

human rights law.” Id. As the Supreme Court has made clear,

however, the expropriation exception is not concerned with

violations of international human-rights law. Philipp, 592 U.S.

at 180. That customary international law has come to protect

the human rights of stateless persons as individuals does not

mean that the international law of property, as a branch of the

law of nations, extends to them similar protections. See

Blanco, supra, at 175-76 (making this point). And, as Philipp

itself pointed out, even international human-rights law itself

traditionally remained “silent . . . on the subject of property

rights.” 592 U.S. at 178. The heirs’ references to various

human-rights treaties that protect the rights of stateless persons,

see 24-7045 Reply Br. 12-13, are therefore beside the point.

In sum, the heirs have not met their burden to show that

we may exercise jurisdiction over these claims on the basis of

the FSIA’s expropriation exception. Philipp requires us to look

only to the international law of property to identify the legal

29

violation for purposes of the expropriation exception. We have

seen no evidence of that body of law’s accommodating the

claims of those who, de facto or otherwise, belong to no state.

C.

That leaves only two remaining claims: the postwar

retakings of In the Studio and Portrait of the Architect. The

district court had earlier sustained jurisdiction over the heirs’

claims to these pieces in de Csepel V, 613 F. Supp. 3d at 289,

300, but, in one of the decisions on appeal before us (de Csepel

VII), the district court reconsidered that determination at

Hungary’s urging and reversed, see 695 F. Supp. 3d at 34-37.

The heirs object to that reconsideration, arguing that there was

no basis for it and that the evidence supports the continued

exercise of jurisdiction.

Assessing these claims requires a fair bit of background on

each painting and the basis for the earlier determinations.

Recall that Hungary regained possession of several pieces of

art in the postwar years as part of a criminal forfeiture. See

supra Section I.B. In de Csepel V, the district court held that

those pieces were taken as part of the Hungarian government’s

criminal proceeding against István’s ex-wife Ilona Kiss for

attempting to smuggle the artworks out of Hungary, and

therefore that any connection to their Holocaust-era taking was

“severed.” 613 F. Supp. 3d at 288. But five of the pieces had

apparently been forfeited to Hungary by mistake, according to

a March 1951 letter from the then-director of the Museum of

Fine Arts, who requested termination of the criminal

attachment. Id. at 288-89; see No. 10-1261, ECF No. 106-6 at

ECF p. 38 (letter). Although no evidence demonstrated

whether the requested termination occurred, the court reasoned

that it could not conclude that those five pieces—still in

defendants’ possession—actually passed to the state in 1950 as

30

part of the forfeiture, rather than at some later point in time for

unknown reasons.

That ambiguity mattered because one of these pieces,

Portrait of the Architect, belonged to András, whose heirs

eventually became Italian citizens—so a later taking from

Italian heirs might avoid the domestic-takings bar. de Csepel

V, 613 F. Supp. 3d at 289. For that piece, the court relied on a

December 1973 letter from the Hungarian Ministry of Culture

that asserted that all of the pieces in the Kiss forfeiture, “insofar

[as] they ha[d] not already passed into the ownership of the

State,” had become state property. Id. Because András’s

daughters were by then Italian citizens and no other evidence

indicated when Portrait of the Architect was taken, the district

court apparently dated the taking to December 1973 and

concluded that it was “an expropriation in violation of

international law over which the Court has jurisdiction.” Id.

As for In the Studio, a piece that belonged to Erzsébet (who

became a U.S. citizen), the district court noted in de Csepel V

that the piece had apparently been deposited with the Museum

of Fine Arts in the 1950s and was mentioned in a May 10, 1966,

letter to that museum from a state political department asking

whether it and several other artworks were indeed in the

museum’s possession. The Museum of Fine Arts’ response did

not confirm its possession of In the Studio. Id. at 299-300.

And, while the December 1973 letter from the Ministry of

Culture listed the piece as having passed to the Hungarian state

by virtue of the 1973 Agreement settling claims with U.S.

citizens, the court observed that as of 2020 the artwork was still

listed as “on deposit” with the Museum, suggesting that at that

point it had not yet been taken. Id. at 300. Because “any taking

after 1973 would be a taking in violation of international law

not settled by the 1973 Agreement,” the court retained

jurisdiction over In the Studio. Id.

31

In their motion to dismiss takings claims as to

twenty-seven of the remaining artworks, defendants challenged

de Csepel V’s determinations in that regard, see Mot. to

Dismiss 11 n.4 (24-7045 J.A. 2072), which the district court

treated as a request for reconsideration, see de Csepel VII, 695

F. Supp. 3d at 34-35. An order denying sovereign immunity is

interlocutory, Exxon Mobil Corp. v. Corporacion CIMEX, S.A.,

111 F.4th 12, 22 (D.C. Cir. 2024), and the district court may

reconsider an interlocutory order “at any time before the entry

of a judgment adjudicating all the claims and all the parties’

rights and liabilities,” Fed R. Civ. P. 54(b); see Langevine v.

District of Columbia, 106 F.3d 1018, 1023 (D.C. Cir. 1997);

United States v. LoRusso, 695 F.2d 45, 53 (2d Cir. 1982). In

the FSIA context, we have further explained that a district

court’s conclusion that it may exercise jurisdiction over a

foreign sovereign “is not a conclusive determination but is

instead subject to change in light of further development of the

facts.” Price, 389 F.3d at 197 (internal quotation marks and

citations omitted); see also Wye Oak Tech., Inc. v. Republic of

Iraq, 24 F.4th 686, 699 (D.C. Cir. 2022) (law-of-the-case

doctrine does not require or permit ignoring jurisdictional

defects). On appeal, the court’s legal conclusions are subject

to de novo review and its findings of fact are reviewed for clear

error. Wye Oak Tech., 24 F.4th at 700.

We see no clear error in the district court’s determination

that it could no longer exercise jurisdiction over either of these

two pieces. As for Portrait of the Architect, the court relied on

a May 1951 letter—not discussed in de Csepel V—that states

that the painting was by that date “transferred to the ownership

of the Museum.” de Csepel VII, 695 F. Supp. 3d at 35-36; see

May 8, 1951 Letter (24-7045 J.A. 2106). Plaintiffs complain

that the May letter itself relies on a document that predates the

March 1951 letter requesting termination of the criminal

attachment, and it is thus not proof that the termination request

32

was not later granted and the painting returned. 24-7045 Heirs’

Br. 54-55. But the court did not clearly err in determining that

documentary evidence plainly indicating that ownership had

“transferred” by May 1951 trumped plaintiffs’ conjecture that

the painting was somehow later returned in response to the

March 1951 letter and then retaken after András’s daughters

became Italian citizens.

Nor did the court clearly err in concluding that In the

Studio was likely taken when it would have been subject to the

1973 Agreement settling all claims of U.S. nationals for pre-

1973 takings. Indeed, the Hungarian government listed the

piece as one of the artworks covered by that agreement, see de

Csepel VII, 695 F. Supp. 3d at 36; de Csepel V, 613 F. Supp.

3d at 300, and the court reasonably credited that clear

documentary proof of transfer over an assertion by plaintiffs’

expert that the piece was still “on deposit” with defendants, see

No. 10-1261, ECF No. 148-2 (Scholl-Tatevosyan Decl.) at

ECF pp. 12-13 & n.4. In addition, Erzsébet had sought

compensation for the painting in 1959 from an earlier claims

commission set up by the United States, and her claim was

“approved and paid in full.” de Csepel VII, 695 F. Supp. 3d at

36. Under U.S. law, determinations of that earlier commission

are “final and conclusive on all questions of law and fact and

not subject to review by any other official of the United States

or by any court by mandamus or otherwise.” 22 U.S.C.

§ 1641m. The fact that Erzsébet successfully claimed In the

Studio as taken by that point means, from the perspective of

U.S. courts, that it has been finally determined that the painting

was taken as of 1959—regardless of what other evidence might

suggest. That, in turn, means that the remaining claims based

on that painting are either subject to the 1973 Agreement or, if

the painting was taken before Erzsébet became a U.S. citizen,

barred by the domestic-takings bar. In either case, we may not

exercise jurisdiction over them.

33

V.

For the foregoing reasons, we affirm the district court’s

dismissals of the family’s claims in its 2023 and 2024 decisions

and thus affirm the dismissal of the de Csepel litigation in its

entirety. We do so cognizant that our ruling will be a

disappointment to a family that has spent decades seeking

redress for the plunder of its property. The Herzogs were

innocent victims of war and genocide, some of the millions of

people for whom no measure of justice has ever been granted.

Their family heirlooms now hang on the walls of public

institutions in Hungary that, to date, have shown no real interest

in atoning for the depredations of that country’s World War

II−era government. The only question we face today, however,

is not whether these plaintiffs deserve justice—they surely

do—but whether Congress has granted U.S. courts the

jurisdiction to provide it. As explained above, it has not.

Unless and until it does, the responsibility for redressing such

historic wrongs must lie elsewhere.

So ordered.