A group of Ecuadorian citizens (the “plaintiffs”) who have sued Chevron Corporation in Ecuador appeal from the district court’s order allowing Chevron to depose their consultant, 3TM. We affirm the district court’s order directing STM to submit to a foundational deposition, subject to the limitation described below.
I.
In 2003, the plaintiffs sued Chevron in Ecuador, seeking to hold Chevron liable as the successor to Texaco Petroleum Company. 1 The plaintiffs allege that Texaco polluted the Ecuadorian Amazon Rainforest over the course of several decades while engaging in oil extraction in the region. This appeal arises out of the plaintiffs’ Ecuadorian lawsuit against Chevron. Specifically, it concerns Richard Stalin Cabrera Vega (“Cabrera”), an individual appointed by the Ecuadorian court to serve as a neutral expert in the Ecuadorian proceedings. The Ecuadorian court ordered Cabrera to draft a report describing the effect of Texaco’s operations on Ecuador’s environment, accompanied by “all the documents that serve as support or a source of information” for the report. The court also ordered that these supporting documents “be provided to the parties” upon the report’s release. In 2008, Cabrera released a report recommending that Chevron be held liable for $27.3 billion in damages, but the Ecuadorian court has yet to render a judgment against Chevron.
Despite Cabrera’s professed impartiality, Chevron claims that Cabrera actually worked closely with the plaintiffs to produce his report, much of which Chevron alleges was secretly ghostwritten by the plaintiffs’ U.S. consultants. Consequently, Chevron has initiated a series of discovery proceedings in the United States under 28 U.S.C. § 1782(a), seeking evidence of collusion between Cabrera and the plaintiffs’ U.S. consultants. Section 1782(a) allows district courts to order discovery in the United States for use in foreign proceedings in certain circumstances.
See, e.g., In re Clerici,
In the proceedings below, Chevron filed a § 1782(a) application seeking discovery from 3TM, an environmental consultancy
*376
firm in Houston. The plaintiffs’ consultant Stratus retained 3TM to assist the plaintiffs in mediation and settlement discussions with Chevron in 2007, and Chevron alleges that 3TM and Stratus produced a report that Cabrera integrated into his report, without disclosing his reliance on it. After the plaintiffs intervened to quash Chevron’s subpoena of 3TM, the district court ordered 3TM to submit to limited discovery. The court concluded that discovery was appropriate based on the
Intel
factors that the Supreme Court has directed courts to consider in reviewing requests for discovery in aid of foreign proceedings.
See Intel Corp. v. Advanced Micro Devices, Inc.,
II.
We review de novo whether the statutory prerequisites for granting § 1782(a) relief are satisfied.
2
See Republic of Kazakhstan v. Biedermann Int’l,
In our view, the district court did not abuse its discretion. First, we find it senseless to require Chevron to seek 3TM documents from Cabrera, given the plaintiffs’ denial that they provided any such documents to Cabrera and Cabrera’s interest in denying receipt of 3TM material. As noted above, the Ecuadorian court ordered Cabrera to disclose all of the source material for his report. Consequently, if Cabrera relied on 3TM documents but did not disclose them, he is unlikely to turn them over now, as doing so would reveal he violated the Ecuadorian court’s order. Second, the record does not clearly demonstrate that Chevron is attempting to evade restrictions on discovery in Ecuador. It is not clear that Chevron ever sought 3TM documents from Cabrera in Ecuador.
4
In any event, even if a request for 3TM documents were pending before the Ecuadorian court, the district court’s decision to grant § 1782(a) relief would not be an abuse of discretion. The plaintiffs have not argued that Chevron’s request is unduly burdensome, and furthermore, there has been no “clear directive” from the Ecuadorian court that it “would reject evidence” produced in the United States.
Euromepa S.A v. R. Esmerian, Inc.,
III.
Even if it is proper to allow discovery under § 1782(a), Chevron may not discover information that is immune from discovery. Section 1782(a) provides that “[a] person may not be compelled to give his testimony or statement or to produce a document or other thing in violation of any legally applicable privilege.” 28 U.S.C. § 1782(a) (2006). Furthermore, the provision’s legislative history suggests that this protection extends to “privileges recognized by foreign law.” S.Rep. No. 88-1580 (1964),
reprinted in
1964 U.S.C.C.A.N. 3782, 3790. We review “factual findings underlying a privilege ruling for clear error and the application of legal principles de novo.”
United States v. Auster,
The plaintiffs argue that 3TM is shielded from discovery under the work product doctrine and the protection accorded non-testifying consultants by Federal Rule of Civil Procedure 26(b)(4)(B).
5
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However, the district court ruled that this protection would be waived for any 3TM documents that were passed to Cabrera. We agree. Although work product immunity is not automatically waived by disclosure of protected material to third parties, disclosure does waive protection if it “has substantially increased the opportunities for potential adversaries to obtain the information.” 8 Charles Alan Wright & Arthur R. Miller,
Federal Practice and Procedure
§ 2024 (3d ed.2010).
6
In this case, the disclosure of 3TM documents to Cabrera, a court-appointed expert, would waive immunity for disclosed documents and possibly others as well. Rule 26(a)(2)(B) provides that when experts testify before a court, they must submit a report disclosing “the data or other information” they have considered in reaching their conclusions. Fed R. Civ. P. 26(a)(2)(B)(ii). Relying on this rule, courts have held that when the work product of non-testifying consultants is provided to testifying experts, immunity is waived for disclosed work product.
See, e.g., Reg’l Airport Auth. of Louisville v. LFG, LLC,
The plaintiffs also contend that 3TM is protected from discovery under Ecuadorian law. As noted above, the legislative history of § 1782(a) suggests that parties may rely on foreign privileges to shield information from discovery in the United States. In our view, however, to avoid “ ‘speculative foray[s] into legal territories unfamiliar to federal judges,’ ” parties must provide “ ‘authoritative proof ” that a foreign tribunal would reject evidence “because of a violation of [an] alleged [foreign] privilege.”
In re Application for an Order Permitting Metallgesellschaft AG to take Discovery,
Even if the disclosure of 3TM documents to Cabrera would waive immunity from discovery, the plaintiffs protest that there is no direct evidence that such a waiver took place.
9
Chevron bears the burden of demonstrating that a waiver of work product protection occurred,
10
and we agree with the plaintiffs that clear evidence of a waiver is lacking.
11
Nevertheless, we believe it was appropriate for the district court to order a foundational deposition in these circumstances, as such a deposition may be used to determine whether any waiver took place. Courts have previously held that “ ‘foundational’ matters,” such as “the date, recipients, and the ‘general nature’ of [a] communication” are not protected by immunity from discovery.
Preferred, Care Partners Holding Corp. v. Humana, Inc.,
Although we approve of the course chosen by the district court, we believe the terms that the court set for the deposition should be further refined. As already explained, the court ordered that 3TM’s deposition be limited to “whether 3TM collaborated with Cabrera” and “the extent to which 3TM recognizes its work in the Cabrera report.” However, the district court did not clearly specify the level of similarity between the Cabrera report and 3TM work product necessary to show that a waiver of immunity from discovery occurred. Depending on 3TM’s interpreta *380 tion of the district court’s order, it could conceivably “recognize” material in the Cabrera report as its own that actually has another provenance. As such, for remand, we stress that similarities between the Cabrera report and 3TM work product are only relevant to the extent that they collectively show that Cabrera more likely than not incorporated 3TM work product into his report. We also note that if disputes between the parties persist after the foundational deposition, the district court may review the Cabrera report and any relevant 3TM work product in camera to help it determine whether a waiver occurred. 13
IV.
Thus, we AFFIRM the district court’s order requiring 3TM to submit to a foundational deposition, and REMAND this case for further proceedings consistent with this opinion.
Notes
. Chevron and Texaco merged in 2001. We note that the nature of the relationship between Chevron and the former Texaco appears to be disputed in the Ecuadorian proceedings.
. One of these statutory prerequisites is that evidence sought in a § 1782(a) application must be “for use” in a foreign proceeding.
Clerici,
. The Supreme Court has suggested that district courts should consider (i) whether "the person from whom discovery is sought is a participant in the foreign proceeding,” since "nonparticipants in the foreign proceeding may be outside the foreign tribunal’s jurisdictional reach” and therefore their evidence may be “unobtainable absent § 1782(a) aid,” (ii) "the nature of the foreign tribunal, the character of the proceedings underway abroad, and the receptivity of the foreign government or the court or agency abroad to U.S. federal-court judicial assistance,” (iii) “whether the § 1782(a) request conceals an attempt to circumvent foreign proof-gathering restrictions or other policies of a foreign country or the United States,” and (iv) whether the § 1782(a) request is "unduly intrusive or burdensome.”
Intel,
. In February 2008, Chevron did request that the Ecuadorian court provide it with copies of documents that the plaintiffs had filed with the court for submission to Cabrera and that the plaintiffs had alleged came from "various Ecuadorian public institutions.” The Ecuadorian court has apparently not yet ruled on this request. However, Chevron’s February 2008 request does not appear to have included a demand for documents created by the plaintiffs' U.S. consultants.
.
See
Fed.R.Civ.P. 26(b)(4)(B) (providing that in most circumstances, "a party may not, by interrogatories or deposition, discover facts known or opinions held by an expert who has been retained or specially employed by another party in anticipation of litigation or to prepare for trial and who is not expected to be called as a witness at trial”);
Shields v. Sturm, Ruger & Co.,
.
See also Fox v. Taylor Diving & Salvage Co.,
. We note that there is some dispute concerning whether Rule 26 mandates the disclosure of "attorney work product” that has been "provided to a testifying expert.”
In re Teleglobe Commc'ns Corp.,
.Chevron has also argued that Cabrera is the equivalent of a court, in that he is similar to a special master, and that consequently 3TM is itself a testifying expert. If this were accepted, the provision of 3TM documents to Cabrera would also waive immunity from discovery, since testifying experts must disclose "the data or other information” they consider in reaching their conclusions. See Fed R. Civ. P. 26(a)(2)(B)(ii).
. The district court seems to have concluded that the plaintiffs conceded in their briefing that Cabrera received documents from 3TM, but this is incorrect. As such, there is no finding of fact that a waiver took place, to which we would defer absent clear error. See
Auster,
. See
Johnson v. Gmeinder,
. Chevron’s motion to supplement the record on appeal is DENIED. Before oral argument, Chevron filed a motion to supplement the record with newly obtained video evidence concerning Cabrera’s contacts with the plaintiffs and Stratus, the consulting firm that retained 3TM. In
Gibson v. Blackburn,
we indicated that typically we will not "enlarge the record to include material not before the district court."
.
See also Ed Tobergte Assocs. Co. v. Russell Brands, LLC,
. Chevron has asked us to rule that discovery need not be limited to the specific 3TM documents that Cabrera received. We leave this issue to be resolved on remand. The district court has not yet definitively ruled on the scope of discovery; it explained that it would return to this issue after the foundational deposition. Furthermore, any decision we reach on the scope of discovery would be mooted if the foundational deposition reveals that no waiver occurred. The district court can determine the proper scope of discovery once it has established whether any waiver took place.
