                  FOR PUBLICATION
  UNITED STATES COURT OF APPEALS
       FOR THE NINTH CIRCUIT

CHRISTOPHER COOK; LEIDRA COOK,          
               Plaintiffs-Appellants,
                 v.                           No. 07-15088
AVI CASINO ENTERPRISES, INC., a                D.C. No.
                                            CV-04-01079-PGR
corporation; IAN DODD; JUAN
MAJIAS; STEPHANIE SHAIK; DEBRA                 OPINION
PURBAUGH; ANDREA CHRISTENSEN,
              Defendants-Appellees.
                                        
        Appeal from the United States District Court
                 for the District of Arizona
        Paul G. Rosenblatt, District Judge, Presiding

                  Argued and Submitted
       September 9, 2008—San Francisco, California

                  Filed November 14, 2008

   Before: Ferdinand F. Fernandez, Ronald M. Gould, and
               Carlos T. Bea, Circuit Judges.

                 Opinion by Judge Gould;
               Concurrence by Judge Gould;
Partial Concurrence and Partial Dissent by Judge Fernandez




                            15379
15382         COOK v. AVI CASINO ENTERPRISES


                       COUNSEL

Bradley L. Booke, Moriarity Badaruddin & Booke, Las
Vegas, Nevada, for the plaintiffs-appellants.

Theodore A. Julian, Jr., Burch & Cracchiolo, P.A., Phoenix,
Arizona, for the defendants-appellees.
                   COOK v. AVI CASINO ENTERPRISES                    15383
                               OPINION

GOULD, Circuit Judge:

   Plaintiff Christopher Cook (“Cook”), a California resident,
seeks recovery for damages suffered as a result of a motor
vehicle accident in which, while on a motorcycle, he was hit
by a drunk driver. The driver was an employee of defendant
Avi Casino Enterprises, Inc. (“ACE”), a tribal corporation,
and she allegedly became intoxicated at an Avi Casino func-
tion. Cook sued the tribal corporation and several of its
employees, alleging negligence and dram shop liability.
Defendants asserted defenses based on federal Indian law.
Defendants claim (1) that there is an absence of subject matter
jurisdiction because the Indian tribe that owns ACE is, like
Cook, a California citizen and (2) that tribal sovereign immu-
nity shields ACE and its employees from suit.

   We affirm the district court, in part on alternate grounds
supported by the record. We agree with Cook that we have
jurisdiction over ACE because there is diversity of citizen-
ship. However, we affirm the dismissal of Cook’s claims
against ACE on the alternate ground of tribal sovereign
immunity. We affirm the district court’s dismissal of defen-
dants Ian Dodd (“Dodd”) and Debra Purbaugh (“Purbaugh”)
on the same ground and do not reach Defendants’ other argu-
ments for dismissal.

                                     I

                                     A

  Christopher Cook seeks relief because employees of Avi
Casino gave an intoxicated fellow employee free drinks, then
drove her to her car; she drove her car into Cook minutes later.1
  1
   Facts regarding the accident are taken from Cook’s complaint. Because
the district court dismissed Cook’s claims pursuant to Federal Rule of
Civil Procedure 12(b)(1), alleged facts not relating to subject matter juris-
diction are assumed to be true. Wah Chang v. Duke Energy Trading and
Marketing, 507 F.3d 1222, 1224 n.1 (9th Cir. 2007).
15384            COOK v. AVI CASINO ENTERPRISES
Andrea Christensen (“Christensen”), a cocktail waitress at
Avi Casino, attended a nighttime birthday party at the casino
for another employee. Defendants Ian Dodd and Debra Pur-
baugh were among the casino employees at the party, during
which Dodd, the on-duty manager, announced that drinks
were “on the house.” Christensen was off-duty, and Purbaugh
served her alcoholic beverages after she was obviously intoxi-
cated.

   Defendants let Christensen board a casino-run shuttle bus
to the employee parking lot so that she could drive home.
Christensen headed north on Aztec Road, which was located
within the Fort Mojave reservation. Leading to the tragic acci-
dent, Cook was driving his motorcycle southbound on the
same road; he was heading home after visiting his mother-in-
law. Minutes after leaving the parking lot, Christensen
swerved across the center line and hit Cook’s motorcycle.2
Cook suffered catastrophic injuries, including the loss of his
left leg, resulting in more than $1,000,000 in medical
expenses. Christensen pled guilty to aggravated assault and
driving under the influence and was sentenced to four years
in Arizona prison. She is not a party to this appeal.

                                  B

   Avi Casino is owned and operated by Avi Casino Enter-
prises, Inc., a corporation organized under the Fort Mojave
Business Corporation Ordinance, which is a tribal law of the
Fort Mojave Indian Tribe (the “Tribe”). The Tribe is a feder-
ally recognized Indian tribe, and its reservation spans Califor-
nia, Nevada, and Arizona. The Tribe’s seat of government is
in Needles, California, but Avi Casino is located on reserva-
tion lands in Nevada, and ACE’s headquarters is in Laughlin,
Nevada. Avi Casino operates under an intergovernmental
agreement between the Tribe and the state of Nevada that per-
  2
   By 4:30 a.m. the following morning, Christensen had a blood alcohol
content of at least 0.25 percent.
                COOK v. AVI CASINO ENTERPRISES             15385
mits the Tribe to operate casinos on tribal lands within the
state.

   ACE is wholly owned and controlled by the Tribe. ACE
shareholder functions are performed by the Fort Mojave
Tribal Council on behalf of and for the benefit of the Tribe.
A majority of ACE’s board of directors must be Tribe mem-
bers. ACE’s articles of incorporation state that all capital sur-
plus not used for corporate development must be deposited in
the Tribe’s general fund.

                               C

  Cook sued ACE, Christensen, Dodd, Purbaugh, and other
casino employees in Arizona federal district court. Cook
sought compensatory and punitive damages for negligence
and dram shop liability under Arizona’s liquor liability statute
and Fort Mojave tribal law.

   All defendants but Christensen filed a motion to dismiss
under Federal Rule of Civil Procedure 12(b)(1), claiming a
lack of diversity jurisdiction. Cook argued that Dodd and Pur-
baugh were citizens of Arizona but conceded that the other
employees named in the complaint were, like Cook, Califor-
nia citizens. On Cook’s recommendation, the district court
dismissed all claims against these other employees, as well as
claims against 25 unnamed defendants. Defendants argued
that ACE was a citizen of California because it was incorpo-
rated under tribal law and the Tribe’s headquarters were in
Needles, California. The district court agreed, applying tradi-
tional corporate citizenship analysis under 28 U.S.C.
§ 1332(a). The court determined that ACE was a citizen of
Nevada because its principal place of business, the casino,
was located there; the court also ruled that ACE was a Cali-
fornia citizen because it was incorporated by the Tribe, and
the Tribe’s headquarters were in California.

   Dodd and Purbaugh then filed a second motion to dismiss,
alleging that as ACE employees they were shielded from lia-
15386           COOK v. AVI CASINO ENTERPRISES
bility by the Tribe’s sovereign immunity, which should
extend to ACE and Avi Casino. The district court granted the
motion, concluding that the Tribe’s sovereign immunity cov-
ered ACE because the corporation functioned as an arm of the
Tribe. It further held that the tribal sovereign immunity cov-
ered Dodd and Purbaugh as tribal employees acting within the
scope of their employment. Although Christensen remains a
defendant in the action, the district court entered a separate
judgment dismissing ACE, Dodd, and Purbaugh. Cook
appealed.

                                II

   We review de novo a district court’s dismissal for lack of
subject matter jurisdiction. Rattlesnake Coalition v. U.S.
Envtl. Prot. Agency, 509 F.3d 1095, 1100 (9th Cir. 2007).
Factual findings relevant to subject matter jurisdiction are
reviewed for clear error. Id. We also review de novo questions
of tribal sovereign immunity. Lineen v. Gila River Indian
Cmty., 276 F.3d 489, 492 (9th Cir. 2002). We may affirm a
district court’s judgment of dismissal on any grounds sup-
ported by the record. Alvarado v. Table Mountain Rancheria,
509 F.3d 1008, 1019 (9th Cir. 2007). Here, we may affirm the
district court’s dismissal on diversity jurisdiction or tribal sov-
ereign immunity grounds. We address both.

                               III

                                A

   [1] We have jurisdiction only if Cook, a resident of Califor-
nia, has citizenship which is diverse from that of every defen-
dant. See Caterpillar, Inc. v. Lewis, 519 U.S. 61, 68 (1996)
(stating that diversity jurisdiction requires “complete diversity
of citizenship”). As the party asserting jurisdiction, Cook has
the burden of proving such diversity exists. Kokkonen v.
Guardian Life Ins. Co. of America, 511 U.S. 375, 377 (1994).
The parties agree that defendants Dodd and Purbaugh have
                COOK v. AVI CASINO ENTERPRISES             15387
citizenship diverse from Cook. The key question is whether
ACE, a tribal corporation, is like Cook a citizen of California.

   [2] An Indian tribe or an unincorporated arm of a tribe is
not a citizen of any state. American Vantage Cos. v. Table
Mountain Rancheria, 292 F.3d 1091, 1098 (9th Cir. 2002).
However, our case law offers little help in determining the cit-
izenship of an Indian corporation created under tribal law. In
Stock West, Inc. v. Confederated Tribes of the Colville Reser-
vation, we asserted in dictum that “[t]here is authority for the
proposition that for purposes of diversity jurisdiction, an
Indian corporation is a citizen of the state in whose borders
the reservation is located.” 873 F.2d 1221, 1226 (9th Cir.
1989). If so, then ACE would be a citizen of California, Ari-
zona, and Nevada because the Fort Mojave reservation spans
all three states. On closer inspection, however, we conclude
that there is no such “authority” for this principle as so
broadly stated. To support its reasoning, Stock West relied on
three decisions of our circuit, all of which held that a tribal
corporation is a citizen of the state where it has its principal
place of business. See R.J. Williams Co. v. Fort Belknap
Hous. Auth., 719 F.2d 979, 982 (stating that tribal corporation
had its “principal place of business in Montana”); R.C. Hed-
reen Co. v. Crow Tribal Hous. Auth., 521 F. Supp. 599, 602-
03 (D. Mont. 1981) (stating that tribal corporation “has its
principal and only place of business in the state of Montana”
and “[a]ccordingly, it is a citizen of the state for purposes of
diversity jurisdiction”); Parker Drilling Co. v. Metlakatla
Indian Cmty., 451 F. Supp. 1127, 1138 (D. Alaska 1978) (“As
[tribal corporation’s] only major business activities, and situs,
are located in Alaska it is an Alaskan corporation for diversity
purposes.”). The tribal reservation in each of those cases was
located in only one state, the same state as the tribal corpora-
tion’s principal place of business. We agree with the district
court’s rejection of the dictum of Stock West. If Stock West
stands for anything on this matter, it is that a tribal corpora-
tion is a citizen of the state where it has its principal place of
business. See William C. Canby, Jr., American Indian Law
15388           COOK v. AVI CASINO ENTERPRISES
223 (4th ed. 2004) (“A tribe may, however, charter a tribal
corporation that becomes a citizen of the state of its principal
place of business . . . .”). But the parties agree that ACE’s
principal place of business is in Nevada, which by itself does
not destroy diversity.

   [3] We are left with what the district court called “an abso-
lute dearth of case law” on this issue. District Court Order at
6. We find some guidance, however, in our decision in Ameri-
can Vantage. Although there we analyzed diversity jurisdic-
tion over an unincorporated casino, we stated that an entity
incorporated under tribal law “is the equivalent of a corpora-
tion created under state or federal law for diversity purposes.”
American Vantage, 292 F.3d at 1099 n.8. We conclude that a
corporation organized under tribal law should be analyzed for
diversity jurisdiction purposes as if it were a state or federal
corporation.

   [4] Under the federal diversity statute, a corporation is a
citizen of (1) “any State by which it has been incorporated”
and (2) “the State where it has its principal place of business.”
28 U.S.C. § 1332(c)(1). ACE is a Nevada citizen because its
principal place of business is there. Defendants claim that
ACE is also a citizen of California because it was incorpo-
rated at the tribal seat of government in Needles, California.
The district court agreed, finding that under the Fort Mojave
Business Corporation Ordinance ACE was incorporated by
the tribal secretary, and Cook offered no evidence to indicate
that the tribal secretary performed these acts anywhere
besides tribal headquarters.

   [5] However, even if it is true that the tribal secretary per-
formed the acts of incorporation in California, ACE is not a
California citizen. The district court stated that a corporation
is a citizen of “any state where it was incorporated.” District
Court Order at 6 (emphasis added) But more precisely, under
28 U.S.C. § 1332(c)(1), a corporation is a citizen of the “state
by which it has been incorporated” (emphasis added). Cf.
                   COOK v. AVI CASINO ENTERPRISES                   15389
Thomson v. Gaskill, 315 U.S. 442, 446 (1942) (“The policy
of the statute conferring diversity jurisdiction upon the district
courts calls for its strict construction.”). We have not focused
on this difference in the past when analyzing non-tribal corpo-
rations. See Industrial Tectronics, Inc. v. Aero Alloy, 912 F.2d
1090, 1092 (9th Cir. 1990) (“For the purposes of diversity
jurisdiction, a corporation is a citizen of any state where it is
incorporated . . . .”) (emphasis added). Here, however, the dis-
tinction is critical. A corporation is a creature of a political
entity. As a tribal corporation, ACE was organized under the
laws of the Fort Mojave Tribe, which is a separate sovereign
independent from state control. See American Vantage, 292
F.3d at 1096 (“Rather than belonging to state political com-
munities, [tribes] are distinct independent political communi-
ties. Tribes also owe no allegiance to a state.”) (citations
omitted). ACE is governed by tribal, not state, corporate law,
and from the state’s perspective a tribal corporation is much
like a foreign corporation. Id. (“Indian tribes fall under nearly
exclusive federal, rather than state, control.”).3 ACE was not
incorporated by virtue of state law, nor does ACE owe its
continuing existence to the state law chartering corporations.
Instead, ACE’s creation and continuance is a function of tribal
law. Although ACE might have been physically present “in”
the state of California when it was created by the Tribe, it was
not created “by” California, as is required by the diversity
statute to establish citizenship. ACE instead was created by
the Tribe.

   There is no conflict between our analysis and the estab-
lished rule that a tribal corporation is a citizen of the state
where it has its principal place of business. While a corpora-
tion is a citizen of the state “by which” it was created, it is
also a citizen of the state “where” it has its principal place of
  3
   Our treatment of tribal corporations as distinct sovereign entities does
not imply that Indian tribes themselves are foreign states. See Allen v.
Gold Country Casino, 464 F.3d 1044, 1047 (9th Cir. 2006) (stating that
an Indian tribe is not a foreign state).
15390            COOK v. AVI CASINO ENTERPRISES
business. 28 U.S.C. § 1332(c)(1). The principal place of busi-
ness clause refers to location and does not require formative
action by or authority of a state leading to creation of a corpo-
ration. Avi Casino is located inside the state of Nevada, and
the business activities of ACE are primarily in Nevada. By
contrast, the incorporation of ACE, its creation and continua-
tion, is a tribal matter, an incident of tribal sovereignty.

   [6] We hold that, for diversity purposes, a tribal corporation
formed under tribal law is not a citizen of a state merely
because its incorporation occurred inside that state. ACE is
thus only a citizen of Nevada, the location of its principal
place of business. We therefore conclude that we have subject
matter jurisdiction over this case because none of the defen-
dants are citizens of California.4

                                 B

  [7] Even though we have diversity jurisdiction, we must
nonetheless dismiss any defendants who are protected by the
Fort Mojave Tribe’s sovereign immunity.

   A sovereign can assert immunity “at any time during judi-
cial proceedings.” In re Jackson, 184 F.3d 1046, 1048 (9th
Cir. 1999). We have occasionally considered the issue sua
sponte. See id. Yet even when a party does not invoke sover-
eign immunity until appeal, it does not waive immunity
unless it voluntarily invokes jurisdiction or makes “a ‘clear
declaration’ that it intends to submit itself to jurisdiction.”
Coll. Sav. Bank v. Fla. Prepaid Postsecondary Educ. Expense
Bd., 527 U.S. 666, 670 (1999). We will entertain a sovereign
immunity defense so long as a defendant provides “fair warn-
ing . . . before the parties and the court have invested substan-
tial resources in the case.” Hill v. Blind Industries and
Services of Maryland, 179 F.3d 754, 758 (9th Cir. 1999).
  4
    We need not address Cook’s claims that ACE was actually incorpo-
rated in Arizona.
                COOK v. AVI CASINO ENTERPRISES             15391
   ACE has objected to our jurisdiction since the beginning.
The tribal corporation did not raise a tribal immunity defense
initially and chose instead to pursue a dismissal on diversity
jurisdiction grounds. Nonetheless, Cook has had fair warning
of ACE’s tribal immunity argument because that immunity is
central to the defense of Dodd and Purbaugh, which on appeal
was argued together with ACE’s diversity claims. See id. at
758. For this reason, we treat the issue as having been fairly
raised.

  [8] Tribal sovereign immunity protects Indian tribes from
suit absent express authorization by Congress or clear waiver
by the tribe. Kiowa Tribe of Oklahoma v. Manufacturing
Technologies, Inc., 523 U.S. 751, 754 (1998). This immunity
applies to the tribe’s commercial as well as governmental
activities. Id. at 754-55. The parties do not dispute that the
Fort Mojave Tribe itself is protected by sovereign immunity,
but they disagree on whether ACE enjoys immunity as a tribal
corporation.

   Cook insists that tribal corporations competing in the eco-
nomic mainstream should not enjoy the same immunity from
suit given to Indian tribes themselves. Cook claims it is unfair
to allow tribes to create commercial corporations that can
compete in the marketplace while enjoying immunity from
the legal liability that all other corporations must face, and he
asserts that granting tribal corporations immunity is unneces-
sary to protect tribal autonomy and self-government. Cook
cites language used by district courts in our circuit and others
showing a reluctance to extend immunity to tribal business
enterprises. See, e.g., Parker Drilling Co. v. Metlakatla Indian
Cmty., 451 F. Supp. 1127, 1137 (D. Alaska 1978) (“Only with
the potential for imposition of tort liability are Indian corpora-
tions truly equal, regardless of the desirability of certain
aspects of that status.”); Namekagon Dev. Co. v. Bois Forte
Reservation Hous. Auth., 395 F. Supp. 23, 29 (D. Minn. 1974)
(“It is repugnant to the American theory of sovereignty that
an instrumentality of the sovereign shall have all the rights
15392             COOK v. AVI CASINO ENTERPRISES
and advantages of a trading corporation, and the ability to sue,
and yet be itself immune from suit . . . .” (quoting Fed. Sugar
Ref. Co. v. U.S. Sugar Equalization Bd., 258 F. 575, 587
(S.D.N.Y. 1920))).

   [9] Cook’s policy arguments are not without some insight
but are foreclosed by our precedent. The Supreme Court has
somewhat grudgingly accepted tribal immunity in the com-
mercial context. Kiowa, 523 U.S. at 758 (“There are reasons
to doubt the wisdom of perpetuating [tribal immunity] . . . .
[T]ribal immunity extends beyond what is needed to safe-
guard tribal self-governance. This is evident when tribes take
part in the Nation’s commerce.”). However, the Court has
also stated that restrictions on tribal immunity are for Con-
gress alone to impose. Id. at 760. And the settled law of our
circuit is that tribal corporations acting as an arm of the tribe
enjoy the same sovereign immunity granted to a tribe itself.
We reaffirmed this rule in Allen, which involved very similar
facts to those raised here. 464 F.3d 1044. In that case, a for-
mer tribal casino employee sued the casino for various
employment violations. We held that whether tribal immunity
extends to a tribal business entity depends not on “whether the
activity may be characterized as a business, which is irrele-
vant under Kiowa, but whether the entity acts as an arm of the
tribe so that its activities are properly deemed to be those of
the tribe.” Id. at 1046. We noted that the tribe authorized the
casino through a tribal ordinance and interstate gaming con-
tract, that the economic advantages created by the casino “in-
ure[d] to the benefit of the Tribe,” and that “[i]mmunity of the
casino directly protect[ed] the sovereign Tribe’s treasury.” Id.
at 1046-47. We concluded that the casino functioned as “an
arm of the Tribe” and accordingly enjoyed tribal immunity.
Id. at 1047.

  [10] The record supports the district court’s conclusion that
ACE and Avi Casino function as an arm of the Fort Mojave
Tribe.5 As in Allen, here the Tribe created ACE pursuant to
  5
   We see no importance in the distinction that here ACE is a tribal cor-
poration while the casino in Allen may have been unincorporated. See
                   COOK v. AVI CASINO ENTERPRISES                    15393
a tribal ordinance and intergovernmental agreement, and the
tribal corporation is wholly owned and managed by the Tribe.
Cook does not contend otherwise. Also as in Allen, the eco-
nomic benefits produced by the casino inure to the Tribe’s
benefit because ACE’s articles of incorporation state that all
capital surplus from the casino shall be deposited in the
Tribe’s treasury and because the Tribe, as the sole share-
holder, enjoys all of the benefits of an increase in the casino’s
value. A majority of ACE’s board must be Tribe members,
and the Tribe’s council performs corporate shareholder func-
tions for the benefit of the Tribe.

   Despite his vigorous arguments that, as a matter of policy,
tribal corporations should be held to lack sovereign immunity,
Cook does not persuasively distinguish Allen’s holding that
these entities already do have sovereign immunity, an issue
squarely presented and decided in Allen. Cook does not dis-
cuss Allen in his brief, and his response at oral argument was
that he was prevented from finding factual distinctions from
Allen by an incorrect discovery order. But we see no evidence
in the record of Cook’s objection to the discovery order, nor
was the issue preserved for appeal. Moreover, the cases Cook
cites in support of his position acknowledge a tribal entity’s
sovereign immunity and concern only whether the entity had
waived that immunity. See, e.g., Parker Drilling, 451 F. Supp.
at 1137. Cook does not contend that ACE has waived tribal
immunity.6

American Vantage, 292 F.3d at 1099 (“A tribe that elects to incorporate
does not automatically waive its tribal sovereign immunity by doing so.”).
See also Canby, supra, at 101-02 (“Incorporation by itself does not waive
immunity.”).
   6
     In a decision subsequently vacated in pertinent part, we once held that
a “sue and be sued” clause in a tribal enabling ordinance may waive tribal
immunity in entities created under that ordinance. Marceau v. Blackfeet
Hous. Auth. (Marceau I), 455 F.3d 974, 978-83 (9th Cir. 2006). Although
we later vacated that holding on tribal exhaustion grounds, so as to facili-
15394              COOK v. AVI CASINO ENTERPRISES
  [11] Allen controls this case and we hold that as a tribal
corporation and an arm of the Fort Mojave Tribe, ACE enjoys
sovereign immunity from Cook’s suit.

                                    C

   [12] The final question is whether ACE’s tribal immunity
extends to two of its employees, defendants Dodd and Pur-
baugh. We conclude that it does. Tribal sovereign immunity
“extends to tribal officials when acting in their official capac-
ity and within the scope of their authority.” Linneen v. Gila
River Indian Community, 276 F.3d 489, 492 (9th Cir. 2002).
In these cases the sovereign entity is the “real, substantial
party in interest and is entitled to invoke its sovereign immu-
nity from suit even though individual officials are nominal
defendants.” Regents of the University of California v. Doe,
519 U.S. 425, 429 (1997). Applying this principle to tribal
rather than state immunity, we have held that a plaintiff can-
not circumvent tribal immunity “by the simple expedient of
naming an officer of the Tribe as a defendant, rather than the
sovereign entity.” Snow v. Quinalt Indian Nation, 709 F.2d
1319, 1322 (9th Cir. 1983). Cook alleges in each substantive
count of his complaint that Dodd and Purbaugh acted in the
course and scope of their authority as casino employees.

tate an initial review of the issue by tribal court, we did not disavow or
reject our initial and now vacated analysis. Marceau v. Blackfeet Hous.
Auth. (Marceau III) 540 F.3d 916, 921 (9th Cir. 2008). Accordingly, the
issue whether a “sue and be sued” clause in a tribe’s enabling ordinance
effectuates a waiver of tribal sovereign immunity remains a live issue for
determination in this circuit. ACE’s enabling ordinance states that corpo-
rations formed by the Tribe may “sue and be sued” in their corporate
name. Writing while Marceau I was still in effect, the district court noted
that ACE might have waived sovereign immunity but declined to analyze
the issue because Cook did not raise it. Cook has not raised this issue on
appeal either, and so we will not decide the issue. See Smith v. Marsh, 194
F.3d 1045, 1052 (9th Cir. 1999) (“[O]n appeal, arguments not raised by
a party in its opening brief are deemed waived.”).
                COOK v. AVI CASINO ENTERPRISES            15395
   [13] We have not yet addressed whether tribal immunity
extends beyond tribal officials to employees of a tribe acting
in their official capacity and within the scope of their author-
ity, but we have extended federal sovereign immunity to
employees of the United States. See Gilbert v. DaGrossa, 756
F.2d 1455, 1458 (9th Cir. 1985) (“[S]overeign immunity can-
not be avoided by naming officers and employees of the
United States as defendants.”). The Second Circuit addressed
this issue and saw no relevant difference between tribal
employees and officials. Chayoon v. Chao, 355 F3d 141, 143
(2d Cir. 2004) (“[Plaintiff] cannot circumvent tribal immunity
by merely naming officers or employees of the Tribe when
the complaint concerns actions taken in defendants’ official or
representative capacities and the complaint does not allege
they acted outside the scope of their authority.”). We reach
the same conclusion. The principles that motivate the immu-
nizing of tribal officials from suit—protecting an Indian
tribe’s treasury and preventing a plaintiff from bypassing
tribal immunity merely by naming a tribal official—apply just
as much to tribal employees when they are sued in their offi-
cial capacity. Here, Cook has sued Dodd and Purbaugh in
name but seeks recovery from the Tribe; his complaint alleges
that ACE is vicariously liable for all actions of Dodd and Pur-
baugh. Plaintiffs such as Cook cannot circumvent tribal
immunity through “a mere pleading device.” Will v. Michigan
Dept. of State Police, 491 U.S. 58, 70-71 (1989). Accord-
ingly, we hold that tribal immunity protects tribal employees
acting in their official capacity and within the scope of their
authority. Cook has sued Dodd and Purbaugh in their official
capacity only, and thus the district court correctly dismissed
them from this suit.

                              IV

   Our conclusion that Cook has established diversity jurisdic-
tion does not change the outcome. The district court properly
dismissed Cook’s claims against ACE and individual defen-
dants Dodd and Purbaugh because all these defendants are
15396           COOK v. AVI CASINO ENTERPRISES
protected by tribal sovereign immunity. Each party shall bear
its own costs on appeal.

  AFFIRMED.



GOULD, Circuit Judge, concurring:

   I am sorry to say that the austerity of our jurisprudence
concerning tribal sovereign immunity leaves me with the con-
clusion that an unjust result is reached that our law might bet-
ter preclude. As the case comes to us, we see Christopher
Cook, catastrophically injured as the result allegedly of gross
and culpable negligence of Avi Casino’s employees. How-
ever, our precedent under Allen makes clear that so long as
Avi Casino Enterprises was acting as an arm of the Tribe,
which appears to be the case, it gains a tribal sovereign immu-
nity commensurate with that of the Tribe itself. From this, it
follows in logic that involved casino employees, when sued
in corporate capacity for torts committed in the course of
employment, also gain immunity. This leaves Mr. Cook with-
out a remedy against Avi Casino for his grave injuries under
our law, even if his assertions of negligence by casino
employees are correct.

   In my view it would be desirable if (1) the United States
Supreme Court on review were to establish a new rule limit-
ing tribal sovereign immunity in this gaming context; or (2)
the Congress were to pass new legislation limiting the sover-
eign immunity of tribal entities involved in ubiquitous com-
mercial gaming activities across the United States; (3) the
Tribe itself were to take responsibility for its casino employ-
ees’ actions, and affirmatively waive sovereign immunity in
this case permitting Cook’s action to be resolved under a liti-
gated adversarial process. Alternatively, my concerns would
be alleviated if one were to hold that the “sue and be sued”
clause in a tribal enabling ordinance effectuated a waiver of
                COOK v. AVI CASINO ENTERPRISES             15397
tribal sovereign immunity (an issue we think not raised on
Cook’s appeal).

   Lest it appear that I am offering a general challenge to the
concept of sovereign immunity for Indian tribes, I clarify that
is not my aim. I have no disagreement with applying the doc-
trine of sovereign immunity to any important actions of
Indian tribes, their officials, corporate arms, and employees
when those actions are aimed at matters of governance of the
Indian nation or policy matters that are critical to their contin-
uation as a tribe. However, I question whether that doctrine
can sensibly be applied to actions wholly commercial in the
gaming area where the tribe has undertaken to compete and
to provide services for the general public. In this sphere our
law can be modified to ensure that the needs of justice for
injured individuals limit the scope of the sovereign immunity
doctrine for Indian tribes engaged in gaming commercial
activities.



FERNANDEZ, Circuit Judge, concurring and dissenting:

   I concur in parts IIIB and C of the majority opinion and in
the result.

   I do not concur in part IIIA. To the extent that it is neces-
sary to opine on diversity jurisdiction, which it probably is
not, I do not agree that there is diversity. We know that a tribe
is not a foreign state. See Stock W., Inc. v. Confederated
Tribes of the Colville Reservation, 873 F.2d 1221, 1226 (9th
Cir. 1989). We know that a tribe is neither a state nor a citizen
of a state, but we treat tribal corporations that way for diver-
sity purposes. See Am. Vantage Cos., Inc. v. Table Mountain
Rancheria, 292 F.3d 1091, 1094 n.1 (9th Cir. 2002); R.J. Wil-
liams Co. v. Fort Belknap Housing Auth., 719 F.2d 979,
982-83 (9th Cir. 1983). We also know that corporations are
usually citizens of the state of incorporation and of the state
15398           COOK v. AVI CASINO ENTERPRISES
where their principal place of business is located. See 28
U.S.C. § 1332(c)(1); Indus. Tectronics, Inc. v. Aero Alloy, 912
F.2d 1090, 1092 (9th Cir. 1990). We also know that this court
has further indicated that, in general, a tribal corporation is a
citizen of the state (here three states) within whose boundaries
the reservation is located. See Stock W., 873 F.2d at 1226.
While the majority rejects the latter proposition, it is one sim-
ple way to resolve the question before us and is no more fic-
tional than the approach adopted by the majority. Finally, if
we are going to apply the usual corporate diversity rule, I see
no principled basis for accepting the fiction that for diversity
purposes a corporation that has its principal place of business
(here its only place of business) on tribal property has its prin-
cipal place of business in a state (Nevada), while rejecting the
fiction that for diversity purposes a state “where” the corpora-
tion was incorporated (here the tribal headquarters in Califor-
nia) is a corporation “of” that state even though it was not
incorporated by that state (California). See Indus. Tectronics,
912 F.2d at 1092 (“a corporation is a citizen of any state
where it is incorporated.”). Especially is that true where the
corporation, as here, is an arm of the tribe.

  Therefore, I respectfully concur in part and dissent in part.
