Defendant-Appellant, a reinsurer, appeals from an order of the Southern District of New York (Swain, C.J.) granting summary judgment to Plaintiff-Appellee, its reinsured. On appeal, Appellant argues that the district court erroneously held that its reinsurance obligations to Appellee are co-extensive with Appellee’s separate insurance obligations to a third party and that it presented no triable issue of fact on its late-notice defense. We disagree. The district court correctly determined that English law, which governs the relevant reinsurance policy, would interpret that policy to provide coverage that is co-extensive with Appellee’s separate insurance obligations. The district court also correctly rejected Appellant’s late-notice defense because Appellant has not shown the sort of extreme facts that would be necessary under English law to support recognition of that defense where, as here, timely notice is not a condition precedent to coverage. We therefore AFFIRM the district court’s order granting summary judgment. GERARD E. LYNCH, C.J. This is a reinsurance dispute between Defendant-Appellant Equitas Insurance Limited (“Equitas”) and Plaintiff-Appellee the Insurance Company of the State of Pennsylvania (“ICSOP”). In the late 1960s, ICSOP provided umbrella insurance to a predecessor of Dole Food Company for a policy period from October 1968 to October 1971 (the “ICSOP-Dole policy”). Equitas then reinsured part of ICSOP’s exposure for the same three-year period. Many years later, in 2009, homeowners in Carson, California, sued Dole for polluting their soil and groundwater. Dole and ICSOP settled those claims and allocated $20 million of the settlement liability to the ICSOP-Dole policy, even though the Carson plaintiffs’ property damages and personal injuries continued to accrue after the ICSOP-Dole policy period had ended. In doing so, the settlement followed California law’s approach to allocation, known as the “all sums rule,” which treats any insurer whose policy was in effect during any portion of the time during which the continuing harm occurred as jointly and severally liable (up to applicable policy limits) for all property damages or personal injuries caused by a pollutant. ICSOP thereafter sought reinsurance coverage from Equitas for its liability, only for Equitas to deny its claim on the basis that English law, which governs the reinsurance policy, would not have allocated ICSOP’s liability on an all sums basis. Instead, Equitas asserted, English law would have prorated ICSOP’s liability based on the number of years it provided coverage to Dole. Accordingly, Equitas contended that its reinsurance obligations were similarly limited. Equitas also defended its denial on the theory that ICSOP had deliberately delayed notice of claim, and thus forfeited any claim under the reinsurance policy. ICSOP then brought this suit, claiming that Equitas was liable on the policy for the reinsured portion of ICSOP’s settlement liability. Rejecting both of Equitas’s arguments for denying coverage, the district court (Laura Taylor Swain, C.J.) granted summary judgment to ICSOP. We agree with the district court. Although the question is not without doubt, we conclude that under the better reading of English law, Equitas’s obligations under the reinsurance policy are co-extensive with ICSOP’s obligations under the ICSOP-Dole policy. The question is not whether English law would have allocated ICSOP’s liability on an all sums basis; English law does not govern ICSOP’s liability. Instead, the question is whether, once ICSOP’s liability was properly allocated, as Equitas concedes that it was, English law would then interpret the reinsurance policy as providing co-extensive coverage. Under English law, there is a strong presumption that facultative reinsurance policies provide back-to-back coverage, meaning that the liability of the insured is generally equivalent to the liability of the reinsured. Searching for a way around that presumption, Equitas urges that the United Kingdom Supreme Court would never apply the back-to-back presumption where, as here, a foreign jurisdiction’s law has the effect of avoiding a reinsurance policy’s coverage period. But the United Kingdom Supreme Court has never limited the presumption in that way, and it has in fact applied a version of the all sums rule in limited instances. Separately, English law has never recognized the defense of full repudiation based on late notice of claim where, as here, timely notice is not a condition precedent to coverage. While Equitas urges that English law would recognize such a defense on extreme facts, no such facts are present here. We therefore AFFIRM the judgment of the district court. BACKGROUND In the late 1960s, a subsidiary of Castle & Cooke Inc. purchased land in Carson, California, where Shell Oil Company had formerly operated an oil and petroleum containment facility. The Castle & Cooke subsidiary demolished the facility and developed a housing tract. Decades later, in 2008, the California Department of Toxic Substances Control tested a site adjacent to the housing tract and found hazardous levels of petroleum hydrocarbons, including benzene, a known carcinogen, in the soil and groundwater. Soon after that discovery, Carson homeowners sued Dole Food Company (with which Castle & Cooke had, by then, merged) and Shell in California state court. According to their complaint, long-term benzene exposure can cause various latent diseases, such as anemia and leukemia, that can manifest many years after exposure. Thus, the homeowners sued for personal injuries and property damage related to the environmental contamination. Shortly after suit was filed in October 2009, Dole notified its insurers. One insurer was ICSOP, a wholly-owned subsidiary of the American International Group, Inc. In 1968, ICSOP had issued umbrella insurance to Castle & Cooke (the “ICSOP-Dole policy”). The ICSOP-Dole policy covers up to $20 million for “all sums” for which Dole might be liable in damages “caused by or arising out of each occurrence happening during” a three-year policy period, from October 1, 1968, to October 1, 1971. J. App’x 754. Dole and its insurers settled the homeowners’ and other related lawsuits, assigning $20 million in liability to the ICSOP-Dole policy — even though that policy contained a three-year coverage period and even though the plaintiffs’ losses accrued over four decades. The parties do not dispute either the fact or the extent of ICSOP’s liability under the ICSOP-Dole policy. As for ICSOP’s liability in general, the ICSOP-Dole policy sets “occurrence” as the relevant thing that must happen during the policy period, id., and it defines occurrence to include “an event or a continuous or repeated exposure to conditions which result in Personal Injury or Property Damage,” id. at 755-56. As for the extent of ICSOP’s liability, the settlement followed the “all sums” rule, a rule that is followed by the State of California, whose laws governed the settlement. See Armstrong World Indus., Inc. v. Aetna Cas. & Sur. Co., 52 Cal. Rptr. 2d 690, 710-11 (Cal. Ct. App. 1996). While the ICSOP-Dole policy is governed by the laws of the State of Hawaii, neither party disputes that Hawaii, like California, follows that rule. See Sentinel Ins. Co., Ltd. v. First Ins. Co. of Hawai’i, Ltd., 875 P.2d 894, 917 (Haw. 1994), as amended (June 24, 1994). As discussed more fully below, the all sums rule applies in long-tail liability cases — cases that involve, for example, injuries that manifest many years after exposure to a pollutant — and holds insurers jointly and severally liable, up to applicable policy limits, for all property damages or personal injuries caused by the pollutant so long as some of the continuing harm occurred while each policy was in effect. See Montrose Chem. Corp. of Cal. v. Superior Ct. of L.A. County, 460 P.3d 1201, 1206-07 (Cal. 2020), as modified (May 27, 2020). To cover part of its losses, ICSOP notified Equitas, its reinsurance carrier, of Dole’s claim against the ICSOP-Dole policy. In 1969, ICSOP had obtained facultative reinsurance1 from underwriters at Lloyd’s of London to hedge some of the risk stemming from the ICSOP-Dole policy; Equitas later inherited those reinsurance obligations from Lloyd’s. The reinsurance policy spans the same three-year period as the ICSOP-Dole policy, and it covers up to $7,234,125 for each $20 million limit that ICSOP pays to Dole. It provides that reinsurance coverage is “[a]s [o]riginal,” J. App’x 779, 796, and it contains a follow-the-settlements clause, which reads: Now We the Underwriters hereby agree to reinsure against loss to the extent and in the manner hereinafter provided. Being a Reinsurance of and warranted same gross rate, terms and conditions as and to follow the settlements of the Company…. Id. at 777, 793. Equitas has refused to cover any portion of ICSOP’s part of the settlement and to pay ICSOP’s claim. In September 2017, ICSOP filed suit against Equitas for reinsurance coverage in the Southern District of New York. At the close of discovery, the parties cross-moved for summary judgment. Equitas principally argued that ICSOP is not entitled to indemnity under the reinsurance policy because, while it did not dispute ICSOP’s liability to Dole under the all sums rule, Equitas’s liability to ICSOP under the reinsurance policy is governed by English law, which does not follow that rule. Equitas also asserted a separate repudiation defense, contending that it may fully repudiate the reinsurance policy because ICSOP deliberately delayed notice of claim for about six years after becoming aware that a claim was likely, and misled Equitas into believing that ICSOP had no claim against the reinsurance policy. For its part, although it agreed that English law governed the reinsurance policy, ICSOP argued that English law would interpret the reinsurance policy as “back-to-back” — that is, providing co-extensive coverage — with the ICSOP-Dole policy. ICSOP also argued that English law has never recognized a defense of full repudiation based on late notice of claim, and that in any event ICSOP’s conduct did not reflect untimely notice or the extreme bad faith that, on one reading of English law, might permit such a defense. The district court agreed with ICSOP, holding that the parties’ obligations are co-extensive and rejecting Equitas’s full repudiation defense. See Ins. Co. of State of Pennsylvania v. Equitas Ins. Ltd., No. 17-6850, 2020 WL 4016815, at *2-5 (S.D.N.Y. July 16, 2020). Consequently, it awarded ICSOP $7,234,125 in damages. Id. at *6. Equitas appeals from that judgment. DISCUSSION We review a grant of summary judgment de novo. Bey v. City of New York, 999 F.3d 157, 164 (2d Cir. 2021). We first consider the scope-of-coverage issue — whether Equitas’s obligations under the reinsurance policy are, as the district court held, co-extensive with ICSOP’s obligations under the ICSOP-Dole policy. We then consider Equitas’s repudiation defense. Because, as the parties agree, English law governs the reinsurance policy, our role is to predict how the United Kingdom Supreme Court would resolve those issues. See Terra Firma Invs. (GP) 2 Ltd. v. Citigroup Inc., 716 F.3d 296, 299-300 (2d Cir. 2013) (predicting that “a rebuttable presumption of reliance” that attaches to some claims for “fraudulent misrepresentation” is “a burden-shifting device” under English law).2 I. Scope of Coverage Under English law, a facultative reinsurance contract is “a separate contract” that “is not an insurance against liability.” Wasa Int’l Ins. Co. v. Lexington Ins. Co. [2010] 1 AC 180 (HL) 32 (Lord Mance); see also Delver v. Barnes [1807] 127 Eng. Rep. 748 (CP) 749-50 (Mansfield, C.J.). Thus, “an insurer seeking indemnity under a reinsurance must, in the absence of special terms, establish both [1] its liability under the terms of the insurance and [2] its entitlement to indemnity under the terms of the reinsurance.” Wasa [2010] 1 AC 180 (HL) 35 (Lord Mance) (emphasis added). To be entitled to indemnity, ICSOP therefore must show that its liability was properly allocated under the terms of the ICSOP-Dole policy and that it is entitled to indemnity for that liability under the reinsurance policy. A. Liability under the ICSOP-Dole Policy Equitas does not dispute ICSOP’s liability to Dole under the ICSOP-Dole policy or the settlement’s apportionment of damages. Nonetheless, because some of Equitas’s arguments against indemnity under the reinsurance policy concern whether English law is receptive to the all sums rule, it is helpful to outline some general principles of American and English law that inform those arguments. Those principles aid our prediction of how the United Kingdom Supreme Court would decide the contested question of indemnity in the reinsurance context. i. American Tort and Insurance Law As one commentator has put it, “[v]ery few developments have ever transformed either tort or insurance law,…and only one[] [development] has transformed both….” Kenneth S. Abraham, The Long-Tail Liability Revolution: Creating the New World of Tort and Insurance Law, 6 U. Pa. J.L. & Pub. Aff. 347, 349 (2021) (emphasis omitted). That development is the rise in tort and insurance litigation concerning “long-tail harms,” a term that “describes a series of indivisible harms, whether bodily injury or property damage, that are attributable to continuous or repeated exposure to the same or similar substances or conditions that take place over multiple years or that have a long latency period.” Restatement of the Law of Liability Insurance §33 cmt. f (Am. L. Inst. 2019) (identifying “asbestos-related bodily injuries and environmental property damage” as two “paradigmatic examples”). In tort law, long-tail harms present “quintessentially difficult causation questions, largely because of the length of time between the defendant’s allegedly tortious conduct and the manifestation of injury, disease, or damage that may have been caused by that conduct.” Abraham, supra, at 357-58. Those quandaries inspired judicial innovations regarding but-for causation. In the seminal case on market-share liability, for example, the Supreme Court of California addressed claims brought by the daughters of mothers who had ingested diethylstilbestrol (“DES”) during their pregnancies, which led to latent injuries manifesting in their daughters many years later. See Sindell v. Abbott Lab’ys, 607 P.2d 924, 925-26 (Cal. 1980). Ordinarily, the doctrine of but-for causation would have required the plaintiff-daughters to prove which of many manufacturers had produced the DES that their mothers had ingested. See id. at 927-28. But the Supreme Court of California relieved them of that near-impossible burden, holding that “[e]ach defendant will be held liable for the proportion of the judgment represented by its share of that market unless it demonstrates that it could not have made the product which caused plaintiff’s injuries.” Id. at 937. Similarly, when it comes to asbestos-related injuries, it is nearly impossible to prove with “absolute certainty which particular exposure to asbestos dust resulted in injury to” a particular plaintiff, especially for an employee who was exposed to several different sources of asbestos from several different employers. Borel v. Fibreboard Paper Products Corp., 493 F.2d 1076, 1094 (5th Cir. 1973). In responding to that issue, courts developed more plaintiff-friendly causation rules. In Borel, for example, the Fifth Circuit (applying Texas law) held that it was enough for a victim of mesothelioma and asbestosis to show that he was tortiously “exposed to the [asbestos-contaminated] products of all the defendants on many occasions.” Id. (emphasis added). Mere tortious exposure was sufficient, the court held, because “[i]t was…established that the effect of exposure to asbestos dust is cumulative, that is, each exposure may result in an additional and separate injury.” Id. Similarly, in Rutherford v. Owens-Illinois, Inc., the Supreme Court of California held that “plaintiffs may prove causation in asbestos-related cancer cases by demonstrating that the plaintiff’s exposure to defendant’s asbestos-containing product in reasonable medical probability was a substantial factor in contributing…to the risk of developing asbestos-related cancer. 941 P.2d 1203, 1219 (Cal. 1997), as modified (Oct. 22, 1997) (first emphasis added; footnote omitted). Under that approach, a plaintiff need not “demonstrate that fibers from the defendant’s particular product were the ones, or among the ones, that actually produced the malignant growth.” Id. (emphasis omitted). Those judicial innovations and others like them expanded the universe of liable defendants, and thus spawned ever more difficult questions concerning how to allocate that liability. Those questions still remain. There appears to be no majority American rule, for instance, governing how to allocate liability when multiple defendants are liable for an indivisible injury — like mesothelioma or other cancers or property damage — flowing from environmental contamination; some jurisdictions appear to employ hybrid approaches to apportioning liability. See Restatement (Third) of Torts: Apportionment Liab. §17 cmt. a (Am. L. Inst. 2000) (collecting various approaches). On the one hand, eight years after Sindell, the Supreme Court of California rejected the imposition of joint-and-several liability in the context of market-share liability, confining liability instead to the defendants’ respective share of the market. See Brown v. Superior Court (Abbott Lab’ys), 751 P.2d 470, 485-87 (Cal. 1988). On the other, the Borel court (again applying Texas law) imposed joint-and-several liability. 493 F.2d at 1095-96. Related developments occurred in the world of insurance law as claims for long-tail harms made their way through the courts. With rising long-tail tort liability and a competitive American insurance market in the 1960s, comprehensive general liability insurance shifted from covering tort liability caused by an “accident,” which arguably covered only abrupt events that resulted in immediate harm, to covering tort liability caused by an “occurrence.” Abraham, supra, at 369-71.3 That change was “a recognition that the policy was to cover liability for harm caused by pollution and other similar, slowly-occurring processes.” Id. at 371. The ICSOP-Dole policy descends from that lineage. Executed in the late 1960s, it covers Dole for “all sums” that Dole “shall be obligated to pay by reason of liability imposed upon [Dole] by law,” and for “all damages, direct or consequential,…on account of personal injuries…and property damage, caused by or arising out of each occurrence happening during the policy period.” J. App’x 754 (emphases added). Notably, the ICSOP-Dole policy defines “occurrence” broadly to include “an event or a continuous or repeated exposure to conditions which result in Personal Injury or Property Damage.” Id. at 755-56 (emphasis added). That language appears to codify the so-called “continuous injury” trigger in insurance law. Whether insurance coverage is “triggered” refers to the question of “what events, from the point of exposure to the point of manifestation, trigger coverage.” Keene Corp. v. Ins. Co. of N. Am., 667 F.2d 1034, 1042 (D.C. Cir. 1981). In answering that question, courts within the United States have developed several approaches: (1) the manifestation theory, where coverage is triggered when an injury manifests, even if the injury occurred many years earlier; (2) the injury-in-fact theory, where coverage is triggered when an injury actually occurs, even if the injury might manifest many years later; (3) the exposure theory, where coverage is triggered when the injured person or property is exposed to the risk that later manifests into harm; and (4) the continuous injury trigger, where coverage is triggered throughout the progression of a disease or property damage, from initial exposure to the risk all the way to manifestation of harm. Restatement of the Law of Liability Insurance §33 cmt. f; see also Sentinel Ins. Co., 875 P.2d at 914-15.4 There is no consensus rule. Importantly for our purposes, California and Hawaii have adopted the continuous injury trigger when interpreting occurrence-based policies like the ICSOP-Dole policy. See Montrose Chem. Corp. of Cal., 460 P.3d at 1206-07; Sentinel Ins. Co., 875 P.2d at 917 (Hawaii law; adopting an “injury-in-fact” theory in general, but adopting the continuous injury theory where the “injury-in-fact occurs continuously over a period covered by different insurers or policies, and actual apportionment of the injury is difficult or impossible to determine”). Hence, there is no dispute that ICSOP was liable to Dole. The extent of ICSOP’s liability to Dole presents a different, though also undisputed, question. The continuous injury trigger implicates distinct allocation issues because that trigger presents circumstances where multiple insurers, like multiple defendants in a tort action, might be liable. It also presents circumstances where, as here, a single insurer is liable even though that insurer provided coverage during only a short part of the period of exposure to the risk that later evolved into harm.5 In those circumstances, some jurisdictions, like California and Hawaii, follow the all sums rule. That rule resolves the allocation issue in favor of the insured by holding the insurer jointly and severally liable for “all sums for property damage attributable to the polluted site, up to their policy limits, if applicable, as long as some of the continuous property damage occurred while each policy was on the loss.” Montrose Chem. Corp. of Cal., 460 P.3d at 1207 (internal quotation marks, citation, and brackets omitted); see also Sentinel Ins. Co., 875 P.2d at 915 (similar under Hawaii law). That rule reflects the understanding that an insurer’s duty to the insured is an issue distinct from apportionment and allocation between multiple insurers. See Armstrong World Indus., Inc., 52 Cal. Rptr. 2d at 710-11, 742. In other words, once an insurer is on the hook for “all sums,” the dispute between the insured and insurer ends, and a contribution dispute between co-insurers begins. In light of that understanding, a policyholder may obtain full recovery from one insurer even if it was insured by several successive insurers or uninsured for part of when the damages accrued. Id. Courts have applied the all sums rule where language in the policy required the insurer to pay “all sums” for which the insured becomes liable on account of an event during the policy period. California v. Cont’l Ins. Co., 281 P.3d 1000, 1007-08 (Cal. 2012), as modified (Sept. 19, 2012); see also Keene Corp., 667 F.2d at 1047-50. The ICSOP-Dole policy contains that language. See J. App’x 754. Thus, Equitas does not dispute the extent of ICSOP’s liability to Dole under California law. An alternative approach is to prorate responsibility “by year among triggered policy years.” Abraham, supra, at 380. For example, “[i]f a $200 million liability triggered twenty policy years, then each policy year would be potentially responsible for its pro-rata share of $10 million.” Id. “There is some disagreement over the precise number of jurisdictions that have adopted each position” — the all sums rule or the pro rata approach — “in part because of variation in policy language and in part because of differing possible interpretations of the holdings in some cases.” Restatement of the Law of Liability Insurance §41 cmt. c. What seems to be clear, however, is that “a significant number of courts” have adopted the all sums rule, “a clear majority” have adopted the pro rata approach, and “many courts have not yet taken a position.” Id.; see also Rossello v. Zurich Am. Ins. Co., 226 A.3d 444, 451 nn.12-13 (Md. 2020) (collecting some of the divide). Whether to relax causation in tort, set a default rule that more expansively triggers insurance coverage, or allocate liability on a pro rata or all sums basis, are quintessentially public policy questions. As a federal court sitting in alienage jurisdiction, it is not our role to answer those questions. Instead, our role is to determine how English law would resolve those issues in the context of reinsurance. How English law has approached those issues in the context of tort liability and insurance is therefore helpful to understanding the parties’ arguments. ii. English Tort and Insurance Law As with American law, we begin our discussion of English law with torts. In Fairchild v. Glenhaven Funeral Services Ltd., the House of Lords heard an appeal involving three claimants whose long-term and substantial exposure to asbestos caused them to develop mesothelioma. [2003] 1 AC 32 (HL)
3-5 (Lord Bingham). The Lords considered whether there were “special circumstances,” in light of the medical uncertainty concerning how asbestos exposure causes mesothelioma, that would justify deviating from the ordinary rule of but-for causation. Id. 9; see also id.
