Montrose Chemical Corp. of Cal. v. Superior Court ( 2020 )


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  •     IN THE SUPREME COURT OF
    CALIFORNIA
    MONTROSE CHEMICAL CORPORATION
    OF CALIFORNIA,
    Petitioner,
    v.
    THE SUPERIOR COURT OF LOS ANGELES COUNTY,
    Respondent;
    CANADIAN UNIVERSAL INSURANCE
    COMPANY, INC., et al.,
    Real Parties in Interest.
    S244737
    Second Appellate District, Division Three
    B272387
    Los Angeles County Superior Court
    BC005158
    April 6, 2020
    Justice Kruger authored the opinion of the Court, in which
    Chief Justice Cantil-Sakauye and Justices Liu, Cuéllar,
    Groban, Elia,* and Brown** concurred.
    *
    Associate Justice of the Court of Appeal, Sixth Appellate
    District, assigned by the Chief Justice pursuant to article VI,
    section 6 of the California Constitution.
    **
    Associate Justice of the Court of Appeal, First Appellate
    District, Division Four, assigned by the Chief Justice pursuant
    to article VI, section 6 of the California Constitution.
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    S244737
    Opinion of the Court by Kruger, J.
    Montrose Chemical Corporation (Montrose) was sued for
    causing continuous environmental damage in the Los Angeles
    area between 1947 and 1982 and subsequently entered into
    partial consent decrees to resolve various claims. Montrose now
    seeks to tap its liability insurance to cover amounts it owes in
    connection with those claims. For each policy year from 1961 to
    1985, Montrose had secured primary insurance and multiple
    layers of excess insurance. This case concerns the sequence in
    which Montrose may access the excess insurance policies
    covering this period.
    Montrose argues it is entitled to coverage under any
    relevant policy once it has exhausted directly underlying excess
    policies for the same policy period. The insurers, by contrast,
    argue that Montrose may call on an excess policy only after it
    has exhausted every lower level excess policy covering the
    relevant years. Reading the insurance policy language in light
    of background principles of insurance law, and considering the
    reasonable expectations of the parties, we agree with Montrose:
    It is entitled to access otherwise available coverage under any
    excess policy once it has exhausted directly underlying excess
    policies for the same policy period. An insurer called on to
    provide indemnification may, however, seek reimbursement
    from other insurers that would have been liable to provide
    1
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    coverage under excess policies issued for any period in which the
    injury occurred.
    I.
    We have previously recounted the basic facts underlying
    this dispute. (See Montrose Chemical Corp. v. Superior Court
    (1993) 
    6 Cal. 4th 287
    , 292–294.) To summarize, Montrose
    manufactured the insecticide dichloro-diphenyl-trichloroethane
    (DDT) at its facility in Torrance from 1947 to 1982. In 1990, the
    United States and the State of California sued Montrose for
    environmental contamination allegedly caused by Montrose’s
    operation of this facility. Montrose entered into partial consent
    decrees in which it agreed to pay for environmental cleanup. To
    meet its obligations, Montrose has now expended millions of
    dollars—Montrose represents the total is more than $100
    million—and asserts that its anticipated future liability could
    approach or exceed this amount.
    Montrose purchased primary and excess comprehensive
    general liability insurance to cover its operations at the
    Torrance facility from defendant insurers between 1961 and
    1985. Primary insurance refers to the first layer of coverage,
    whereby “liability attaches immediately upon the happening of
    the occurrence that gives rise to liability.” (Olympic Ins. Co. v.
    Employers Surplus Lines Ins. Co. (1981) 
    126 Cal. App. 3d 593
    ,
    597.) Excess insurance, by contrast, “refers to indemnity
    coverage that attaches upon the exhaustion of underlying
    insurance coverage for a claim.” (County of San Diego v. Ace
    Property & Casualty Ins. Co. (2005) 
    37 Cal. 4th 406
    , 416, fn. 4.)
    An excess insurer’s coverage obligation begins once a certain
    level of loss or liability is reached; that level is generally referred
    to as the “attachment point” of the excess policy. (Rest., Liability
    2
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    Insurance, § 39, com. d, p. 338.) Here, 40 insurers collectively
    issued more than 115 excess policies during the 1961 to 1985
    period, which collectively provide coverage sufficient to
    indemnify Montrose’s anticipated total liability.
    Montrose and the insurers, which are the real parties in
    interest here,1 agree for purposes of this dispute that Montrose’s
    1
    The real party insurers are:     Continental Casualty
    Company and Columbia Casualty Company, joined by AIU
    Insurance Company; Allstate Insurance Company (solely as
    successor in interest to Northbrook Excess and Surplus
    Insurance Company); American Centennial Insurance
    Company; American Home Assurance Company; Federal
    Insurance Company; Employers Insurance of Wausau; Everest
    Reinsurance Company (as successor in interest to Prudential
    Reinsurance Company); Fireman’s Fund Insurance Company;
    General Reinsurance Corporation; Granite State Insurance
    Company; Lamorak Insurance Company (formerly known as
    OneBeacon America Insurance Company, as successor in
    interest to Employers Commercial Union Insurance Company of
    America, The Employers Liability Assurance Corporation, Ltd.,
    and Employers Surplus Lines Insurance Company); Employers
    Mutual Casualty Company; Landmark Insurance Company;
    Lexington Insurance Company; Mt. McKinley Insurance
    Company (as successor in interest to Gibraltar Casualty
    Company); Munich Reinsurance America, Inc. (formerly known
    as American Re-Insurance Company); National Surety
    Corporation; National Union Fire Insurance Company of
    Pittsburgh, PA; New Hampshire Insurance Company; North
    Star Reinsurance Corporation; Providence Washington
    Insurance Company (as successor by way of merger to Seaton
    Insurance Company, formerly known as Unigard Security
    Insurance Company, formerly known as Unigard Mutual
    Insurance Company); Transport Insurance Company (as
    successor in interest to Transport Indemnity Company);
    Westport Insurance Corporation (formerly known as Puritan
    Insurance Company, formerly known as The Manhattan Fire
    3
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    primary coverage has been exhausted.            Further, the parties
    have stipulated to the relevant language found in the excess
    policies.2 Specifically, each policy provides that Montrose must
    exhaust the limits of its underlying insurance coverage before
    there will be coverage under the policy. The policies describe
    the applicable underlying coverage in four main ways:
    1.   Some policies contain a schedule of underlying
    insurance listing all of the underlying policies in the same policy
    period by insurer name, policy number, and dollar amount.
    2. Some policies reference a specific dollar amount of
    underlying insurance in the same policy period and a schedule
    of underlying insurance on file with the insurer.
    3. Some policies reference a specific dollar amount of
    underlying insurance in the same policy period and identify one
    or more of the underlying insurers.
    4. Some policies reference a specific dollar amount of
    underlying insurance that corresponds with the combined limits
    of the underlying policies in that policy period.
    and Marine Insurance Company); Zurich International
    (Bermuda), Ltd.
    Insurers Travelers Casualty and Surety Company
    (formerly known as Aetna Casualty and Surety Company) and
    The Travelers Indemnity Company opposed Montrose on
    independent grounds and filed a separate answering brief.
    2
    The record does not contain complete copies of every policy
    between Montrose and the insurers. Instead, the parties have
    identified the terms of these policies that they believe are
    sufficient to resolve this dispute. The parties agree the various
    policies use different language that all communicates the same
    exhaustion requirement in different ways.
    4
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    In a variety of ways, the excess policies also provide that
    “other insurance” must be exhausted before the excess policy
    can be accessed. Relevant examples include the following:
    • Some policies provide that they will “indemnify the
    insured for the amount of loss which is in excess of the
    applicable limits of liability of the [scheduled] underlying
    insurance,” and then define “loss” as “the sums paid as
    damages in settlement of a claim or in satisfaction of a
    judgment for which the insured is legally liable, after
    making deductions for all recoveries, salvages and other
    insurances (whether recoverable or not) other than the
    underlying insurance and excess insurance purchased
    specifically to be in excess of this policy.” (Italics added.)
    • Some policies state that the insurer is liable for “the
    ultimate net loss in excess of the retained limit” and define
    “retained limit” to mean, among other things, the “total of
    the applicable limits of the underlying policies listed in [a
    schedule] [and] the applicable limits of any other
    underlying insurance collectible by the insured.” (Italics
    added.)
    • Under a “Loss Payable” provision, one policy provides it
    will pay “any ultimate net loss,” which is separately
    defined as “the sums paid in settlement of losses for which
    the Insured is liable after making deductions for all
    recoveries, salvages and other insurance (other than
    recoveries under the underlying insurance, policies of co-
    insurance, or policies specifically in excess hereof).” (Italics
    added.)
    • Under a “Limits” provision, some policies provide that “the
    insurance afforded under this policy shall apply only after
    5
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    all underlying insurance has been exhausted.”        (Italics
    added.)
    • One policy states that “[i]f other valid and collectible
    insurance with any other insurer is available to the
    Insured covering a loss also covered by this policy, other
    than insurance that is in excess of the insurance afforded
    by this policy, the insurance afforded by this policy shall
    be in excess of and shall not contribute with such other
    insurance.” (Italics added.)
    Montrose and the insurers disagree whether these
    clauses—which we will collectively call “other insurance”
    clauses—require Montrose to exhaust other insurance coverage
    from other policy periods. This dispute dates to 1990, when
    Montrose first sued its insurers to resolve various coverage
    disputes, but the relevant filing for our purposes occurred in
    2015, when Montrose’s fifth amended complaint asserted a new
    cause of action seeking the following declaration:
    “a. In order to seek indemnification under the Defendant
    Insurers’ excess policies, Montrose need only establish that its
    liabilities are sufficient to exhaust the underlying policy(ies)
    in the same policy period, and is not required to establish that
    all policies insuring Montrose in every policy period (including
    policies issued to cover different time periods both before and
    after the policy period insured by the targeted policy) with limits
    of liability less than the attachment point of the targeted policy,
    have been exhausted; and
    “b. Montrose may select the manner in which [to] allocate
    its liabilities across the policy(ies) covering such losses.”
    6
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    The rule Montrose proposes in its amended complaint is a
    rule of “vertical exhaustion” or “elective stacking,” whereby it
    may access any excess policy once it has exhausted other policies
    with lower attachment points in the same policy period. The
    insurers, in contrast, each of which has issued an excess policy
    to Montrose in one of the triggered policy years, argue for a rule
    of “horizontal exhaustion,” whereby Montrose may access an
    excess policy only after it has exhausted other policies with
    lower attachment points from every policy period in which the
    environmental damage resulting in liability occurred. The
    parties filed cross-motions for summary adjudication of this
    issue.3
    The trial court denied Montrose’s motion and granted the
    insurers’ motion, holding that the excess policies required
    horizontal exhaustion in the context of this multiyear injury.
    The court concluded there is a “ ‘well-established rule that
    horizontal exhaustion should apply in the absence of policy
    language specifically describing and limiting the underlying
    insurance.’ ” Montrose filed a petition for a writ of mandate,
    3
    One set of insurers, Travelers Casualty and Surety
    Company and The Travelers Indemnity Company (collectively,
    Travelers), opposed Montrose’s motion for summary
    adjudication for two independent reasons. First, Travelers
    argued that Montrose’s requested declaration would entitle
    Montrose to indemnification without actually exhausting the
    relevant underlying insurance, as required by the terms of the
    Travelers policies. Travelers further argued that California law
    did not apply to their policies. Because the Court of Appeal
    concluded for other reasons that Montrose was not entitled to
    summary adjudication, it did not address the issues raised by
    Travelers. We did not grant review of either question, as
    discussed at part II.D., post.
    7
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    which the Court of Appeal summarily denied.            We granted
    Montrose’s petition for review and transferred the case to the
    Court of Appeal with instructions to issue an order to show
    cause why the relief Montrose sought should not be granted.
    The Court of Appeal affirmed the trial court’s denial of
    Montrose’s motion for summary adjudication and affirmed in
    part the trial court’s grant of the insurers’ parallel motion.
    (Montrose Chemical Corp. v. Superior Court (2017) 
    14 Cal. App. 5th 1306
    , 1321, 1338 (Montrose II).)         The court
    concluded that the plain language of many of the excess policies
    purchased by Montrose provide that they “attach not upon
    exhaustion of lower layer policies within the same policy period,
    but rather upon exhaustion of all available insurance.” (Id. at
    p. 1327.)
    Shortly after the Court of Appeal published its opinion in
    this case, another Court of Appeal disagreed with its reasoning
    in State of California v. Continental Ins. Co. (2017) 
    15 Cal. App. 5th 1017
    . The court in that case determined that
    vertical exhaustion was appropriate given the relevant policy
    language and our case law. (Id. at pp. 1031–1037.)
    We granted review in this case to determine whether
    vertical exhaustion or horizontal exhaustion is required when
    continuous injury occurs over the course of multiple policy
    periods for which an insured purchased multiple layers of excess
    insurance. Reading the relevant policy language in light of
    background principles of insurance law and considering the
    parties’ reasonable expectations, we conclude that a rule of
    vertical exhaustion is appropriate. Under that rule, the insured
    has access to any excess policy once it has exhausted other
    directly underlying excess policies with lower attachment
    8
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    points, but an insurer called upon to indemnify the insured’s loss
    may seek reimbursement from other insurers that issued
    policies covering relevant policy periods.4
    II.
    A.
    We begin our analysis with a few background insurance
    law principles specific to the continuous or “long-tail” injury at
    issue here, where damage occurs over multiple policy periods.
    (See State of California v. Continental Ins. Co. (2012) 
    55 Cal. 4th 186
    , 195–196 (Continental).) In a much earlier iteration of this
    case, we noted “the settled rule” is that “an insurer on the risk
    when continuous or progressively deteriorating damage or
    injury first manifests itself remains obligated to indemnify the
    insured for the entirety of the ensuing damage or injury,” up to
    the policy’s limit. (Montrose Chemical Corp. v. Admiral Ins. Co.
    (1995) 
    10 Cal. 4th 645
    , 686, italics added (Montrose I).) “There
    is no requirement that . . . the conditions giving rise to the
    damage or injury . . . themselves occur within the policy period
    in order for potential liability coverage to arise.” (Ibid.)
    Extending this logic to the continuous injury context, we held
    that “bodily injury and property damage which is continuous or
    progressively deteriorating throughout several policy periods is
    potentially covered by all policies in effect during those periods.”
    (Id. at p. 689.) This principle is also known as the “continuous
    injury trigger of coverage.” (Ibid.)
    4
    Because the question is not presented here, we do not
    decide when or whether an insured may access excess policies
    before all primary insurance covering all relevant policy periods
    has been exhausted.
    9
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    In Aerojet-General Corp. v. Transport Indemnity Co.
    (1997) 
    17 Cal. 4th 38
    , 57 (Aerojet), we illustrated the principle
    with an example: If an insured company discharges a hazardous
    substance that causes property damage in the amount of
    $100,000 each year for a span of 30 years, a $1 million insurance
    policy that is purchased for the first year of that 30-year span
    would be required to pay the insured the full $1 million limit for
    indemnification. Even though the damage traceable to the
    policy year in which the insurance policy was in effect only
    amounted to $100,000, the insurer is liable for all damages. As
    we explained, the insurer’s obligation to pay is “triggered if
    specified harm is caused by an included occurrence, so long as
    at least some such harm results within the policy period.” (Id.
    at p. 56, fn. omitted, citing Montrose 
    I, supra
    , 10 Cal.4th at
    pp. 669–673.) “It extends to all specified harm caused by an
    included occurrence, even if some such harm results beyond the
    policy period.” (Aerojet, at pp. 56–57.)
    This “all sums” rule, as we described it in Aerojet, means
    that “insurers [a]re responsible for defending the insured for all
    claims that involved the triggering damage” in a continuous
    injury case; “as long as the policyholder is insured at some point
    during the continuing damage period, the insurers’ indemnity
    obligations persist until the loss is complete, or terminates.”
    
    (Continental, supra
    , 55 Cal.4th at p. 197, citing 
    Aerojet, supra
    ,
    17 Cal.4th at p. 71; Continental, at p. 200 [under all sums
    allocation, insurers must “pay 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’ ”].) We adopted this
    rule because, contrary to Aerojet’s stylized example, “[i]t is often
    10
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    ‘virtually impossible’ for an insured to prove what specific
    damage occurred during each of the multiple consecutive policy
    periods in a progressive property damage case.” (Id. at p. 196.)
    “If such evidence were required, an insured who had procured
    insurance coverage for each year during which a long-tail injury
    occurred likely would be unable to recover.” (Ibid.) The all sums
    approach, we explained, “best reflects the insurers’ indemnity
    obligations under the respective policies, the insured’s
    expectations, and the true character of the damages that flow
    from a long-tail injury.” (Id. at p. 200.)
    Finally, recognizing that the limits of any one policy may
    be insufficient to cover the entire liability resulting from a
    continuous injury, we concluded in Continental that the insured
    may seek indemnification from every policy that covered a
    portion of the loss, up to the full limits of each policy.
    
    (Continental, supra
    , 55 Cal.4th at p. 200.) This “all-sums-with-
    stacking indemnity principle,” we said, “properly incorporates
    the Montrose [I] continuous injury trigger of coverage rule and
    the Aerojet all sums rule, and ‘effectively stacks the insurance
    coverage from different policy periods to form one giant “uber-
    policy” with a coverage limit equal to the sum of all purchased
    insurance policies.’ ” (Id. at p. 201.) “ ‘[T]his approach treats all
    the triggered insurance as though it were purchased in one
    policy period’ ” and recognizes “the uniquely progressive nature
    of long-tail injuries that cause progressive damage throughout
    multiple policy periods.” (Ibid.) Importantly, “the insured has
    immediate access to the insurance it purchased.” (Ibid.) The
    insurers can then sort out their proportional share through
    actions for equitable contribution or subrogation. (Id. at p. 200;
    11
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    see Continental Cas. Co. v. Zurich Ins. Co. (1961) 
    57 Cal. 2d 27
    ,
    37.)5
    Having adopted an all-sums-with-stacking approach to
    the coverage of long-tail injuries, we are now presented with a
    follow-on question: In what order may an insured access excess
    policies from different policy periods to cover liability arising
    from long-tail injuries? To illustrate the parties’ competing
    approaches, consider a hypothetical company that caused
    property damage over three years that resulted in $90 million of
    damage. Further imagine that in each of these three years, the
    company had purchased primary insurance with a $10 million
    limit and two layers of excess insurance, each providing an
    additional $10 million of coverage:
    5
    In a contribution action, an insurer that paid more than
    its share in the initial coverage action can seek reimbursement
    from other insurers that were obligated to indemnify or defend
    the same loss or claim. (Fireman’s Fund Ins. Co. v. Maryland
    Casualty Co. (1998) 
    65 Cal. App. 4th 1279
    , 1293.) The doctrine of
    equitable subrogation allows an insurer to stand in the shoes of
    the insured and recover from third parties that are liable to the
    insured for a loss that the insurer both insured and paid. (Id. at
    pp. 1291–1292.) As a general matter, these types of actions
    allow insurers to apportion liability for losses among themselves
    after the insured has been indemnified.
    12
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    Year 1            Year 2              Year 3
    $50 million
    $40 million
    $30 million      Policy 2A         Policy 2B           Policy 2C
    $20 million      Policy 1A         Policy 1B           Policy 1C
    $10 million      Primary           Primary             Primary
    Insurance         Insurance           Insurance
    We are tasked with deciding between two proposed
    methods by which these six excess insurance policies might be
    stacked after the primary insurance has been exhausted to cover
    the $90 million liability in a way that “ ‘treats all the triggered
    insurance as though it were purchased in one policy period.’ ”
    
    (Continental, supra
    , 55 Cal.4th at p. 201.) Under the insurers’
    proposed rule of horizontal exhaustion, the insured would have
    to exhaust all of its lower layer excess coverage across all
    relevant policy periods before accessing any of its higher layer
    coverage:
    13
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    $90 million          Policy 2C
    $80 million          Policy 2B
    $70 million          Policy 2A
    $60 million          Policy 1C
    $50 million          Policy 1B
    $40 million          Policy 1A
    $30 million          Primary
    Insurance
    $20 million          Primary
    Insurance
    $10 million          Primary
    Insurance
    Under Montrose’s proposed rule of vertical exhaustion, in
    contrast, an insured would be permitted to access any higher
    layer excess policy once it has exhausted the directly underlying
    excess policy covering the same period:
    14
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    $90 million         Policy 2C
    $80 million         Policy 1C
    $70 million         Policy 2B
    $60 million         Policy 1B
    $50 million         Policy 2A
    $40 million         Policy 1A
    $30 million         Primary
    Insurance
    $20 million         Primary
    Insurance
    $10 million         Primary
    Insurance
    Which approach applies depends on the terms of the
    parties’ agreement. We therefore begin by looking, as we must,
    to the language of the insurance policies at issue. (Minkler v.
    Safeco Ins. Co. of America (2010) 
    49 Cal. 4th 315
    , 321 (Minkler);
    AIU Ins. Co. v. Superior Court (1990) 
    51 Cal. 3d 807
    , 822–823.)
    B.
    “The principles governing the interpretation of insurance
    policies in California are well settled. ‘Our goal in construing
    insurance contracts, as with contracts generally, is to give effect
    to the parties’ mutual intentions. [Citations.] “If contractual
    language is clear and explicit, it governs.” [Citations.] If the
    terms are ambiguous [i.e., susceptible of more than one
    reasonable interpretation], we interpret them to protect “ ‘the
    15
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    objectively   reasonable    expectations      of   the   insured.’ ” ’ ”
    
    (Minkler, supra
    , 49 Cal.4th at p. 321.) If these rules do not
    resolve an ambiguity, we may then “ ‘resort to the rule that
    ambiguities are to be resolved against the insurer.’ ” (Ibid.)
    The parties’ dispute centers on the meaning of the “other
    insurance” clauses in the excess insurance policies. These
    clauses provide, in a variety of ways, that each policy shall be
    excess to other insurance available to the insured, whether or
    not the other insurance is specifically listed in the policy’s
    schedule of underlying insurance. The insurers argue that these
    clauses call for a rule of horizonal exhaustion because they
    restrict indemnification from any excess policy until the insured
    has exhausted all other available insurance—which, in a case of
    long-tail injury, means every policy with a lower attachment
    point from every policy period triggered by the continuous
    injury.
    Although    the   insurers’     interpretation     is   not    an
    unreasonable one, it is not the only possible interpretation of the
    policy language.6 The “other insurance” clauses at issue clearly
    6
    Nor, contrary to the insurers’ suggestion, has this
    interpretation already been adopted in California cases. The
    insurers invoke various cases interpreting “other insurance”
    clauses in other settings, but none addresses the question here:
    whether “other insurance” clauses require horizontal
    exhaustion of excess insurance policies in cases involving long-
    tail injury. (See, e.g., Legacy Vulcan Corp. v. Superior Court
    (2010) 
    185 Cal. App. 4th 677
    , 689–690 [addressing defense
    obligations of a policy providing both excess and “umbrella”
    defense coverage]; Peerless Cas. Co. v. Continental Cas. Co.
    (1956) 
    144 Cal. App. 2d 617
    , 625–626 [excess insurer not required
    to contribute when insurance settlement was prorated across
    16
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    require exhaustion of underlying insurance, but none clearly or
    explicitly states that Montrose must exhaust insurance with
    lower attachment points purchased for different policy periods.
    Policies that disclaim coverage for amounts covered by “other
    underlying insurance,” or require exhaustion of “all underlying
    insurance,” for example, could fairly be read to refer only to
    other directly underlying insurance in the same policy period
    that was not specifically identified in the schedule of underlying
    insurance, anticipating that the scheduled underlying
    insurance may later be replaced or supplemented with different
    policies.
    Other formulations require deductions for, in the words of
    one set of representative policies, all “other insurances (whether
    recoverable or not) other than the underlying insurance and
    excess insurance purchased specifically to be in excess of this
    policy.” (Italics added.) If this language were read to apply to
    insurance purchased for other policy periods, it could fairly be
    understood to require the exhaustion of every other insurance
    policy at every attachment point—not merely, as the insurers’
    theory of horizontal exhaustion would have it, excess policies
    from other policy periods that contain lower attachment points.
    The insurers do not advance this expansive reading, however;
    they contend that the reference to “other insurance,” properly
    understood, means “other underlying insurance”—that is, only
    excess insurance with lower attachment points from all relevant
    policy periods. The insurers do not explain why the reference is
    not properly understood to mean “other directly underlying
    two primary insurers and at least one primary policy remained
    unexhausted].)
    17
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    insurance”—that is, a requirement that the insured exhaust
    only excess insurance with lower attachment points from the
    same policy period. This is one clue that the plain language of
    these clauses is not adequate to resolve the dispute in the
    insurers’ favor.
    Consideration of the traditional use of “other insurance”
    clauses reinforces our doubts about the insurers’ interpretation.
    As we have previously explained, “ ‘[h]istorically, “other
    insurance” clauses were designed to prevent multiple recoveries
    when more than one policy provided coverage for a particular
    loss.’ ” (Dart Industries, Inc. v. Commercial Union Ins. Co.
    (2002) 
    28 Cal. 4th 1059
    , 1079 (Dart).) They have not generally
    been understood as dictating a particular exhaustion rule for
    policyholders seeking to access successive excess insurance
    policies in cases of long-tail injury.
    In Dart, we considered the meaning of an “other
    insurance” clause in a different context. There, the policyholder
    had acquired successive primary policies covering multiple
    decades and subsequently sought defense and indemnity from
    one of its primary insurers for a continuous injury during that
    time even though the policy provided by that insurer had been
    lost or destroyed. 
    (Dart, supra
    , 28 Cal.4th at pp. 1064–1065.)
    The policyholder was able to prove the material terms of the
    policy, but the insurer argued that its contractual obligations
    may have been relieved or reduced by an “other insurance”
    clause in the lost policy, pointing to the other policies purchased
    for the period during which the injury occurred. (Id. at p. 1078.)
    We rejected this argument, explaining that reliance on an “other
    insurance” clause could not be used to “defeat the insurer’s
    obligations altogether.” (Id. at p. 1079.) In other words, the
    18
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    insurer in Dart could not simply invoke the possibility of an
    “other insurance” clause to escape its coverage obligations. We
    reasoned, in a passage the parties have focused on here:
    “ ‘[A]pportionment among multiple insurers must be
    distinguished from apportionment between an insurer and its
    insured. When multiple policies are triggered on a single claim,
    the insurers’ liability is apportioned pursuant to the “other
    insurance” clauses of the policies [citation] or under the
    equitable doctrine of contribution [citations].                   That
    apportionment, however, has no bearing upon the insurers’
    obligations to the policyholder. . . . The insurers’ contractual
    obligation to the policyholder is to cover the full extent of the
    policyholder’s liability (up to the policy limits).’ ” (Id. at p. 1080,
    quoting Armstrong World Industries, Inc. v. Aetna Casualty &
    Surety Co. (1996) 
    45 Cal. App. 4th 1
    , 105–106.)
    The parties dispute whether Dart meant to set out a
    categorical view of the meaning of “other insurance” clauses in
    cases of continuous injury and whether that view forecloses the
    insurers’ proposed interpretation of the “other insurance”
    clauses in the distinct context we confront here. Citing Dart,
    Montrose asserts that the “other insurance” clauses are relevant
    to contribution actions between insurers but not to coverage
    actions between insurers and policyholders. (See State of
    California v. Continental Ins. 
    Co., supra
    , 15 Cal.App.5th at
    p. 1032.) We need not rely on any such categorical rule in this
    case, however; it is enough to observe that Dart undermines the
    insurers’ claim that the “other insurance” clauses clearly and
    explicitly call for a rule of horizontal exhaustion.
    In rejecting the insurer’s claim in Dart, we emphasized
    that “other insurance” clauses have not traditionally been used
    19
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    to address questions concerning the obligation of successive
    insurers to indemnify policyholders for a continuously
    manifesting injury (a question which, as Dart reminds us, “is a
    separate issue from the obligations of the insurers to each other”
    
    (Dart, supra
    , 28 Cal.4th at p. 1080)). (Id. at p. 1078, fn. 6.)
    Elaborating on the same point, the Restatement explains that
    “other insurance” clauses have generally been used to address
    “[a]llocation questions with respect to overlapping concurrent
    policies.” (Rest., Liability Insurance, supra, § 40, com. c, p. 345,
    italics added.) Consistent with this understanding, most courts
    to address the issue have found that “other insurance” clauses
    are not aimed at governing the proper allocation of liability
    among successive insurers in cases of long-tail injury or the
    appropriate sequence in which a policyholder may access its
    insurance across several policy periods. (Id., § 41, com. j, p. 361;
    see In re Viking Pump, Inc. (2016) 
    27 N.Y.3d 244
    , 266 [
    52 N.E.3d 1144
    , 1157] [holding that “other insurance” clauses do not
    mandate horizontal exhaustion under all sums allocation, and
    explaining that “ ‘other insurance’ clauses ‘apply when two or
    more policies provide coverage during the same period, and they
    serve to prevent multiple recoveries from such policies’ . . . .
    [O]ther insurance clauses are not implicated in situations
    involving successive—as opposed to concurrent—insurance
    policies”]; see also Steadfast Insurance Co. v. Greenwich Ins.
    (2019) 
    385 Wis. 2d 213
    , 228 [
    922 N.W.2d 71
    , 79] [“ ‘The accepted
    meaning of “other insurance” provisions does not include
    application to successive insurance policies.’ ”]; Ohio Cas. Ins.
    Co. v. Unigard Ins. Co. (Utah 2012) 
    268 P.3d 180
    , 184 [“ ‘[O]ther
    insurance’ provisions do not apply to successive insurers.”];
    Boston Gas Co. v. Century Indem. Co. (2009) 
    454 Mass. 337
    , 361
    20
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    [
    910 N.E.2d 290
    , 308] [“ ‘[O]ther insurance’ clauses simply
    reflect a recognition of the many situations in which concurrent,
    not successive, coverage would exist for the same loss.”];
    Benjamin Moore & Co. v. Aetna Cas. (N.J. 2004) 
    843 A.2d 1094
    ,
    1101 [“ ‘[O]ther insurance’ clauses, which are provisions
    typically designed to preclude a double recovery when multiple,
    concurrent policies provide coverage for a loss[,] . . . [are] not
    generally applicable in the continuous-trigger context where
    successive rather than concurrent policies [are] at issue.”].)
    Given the generally understood purpose of “other insurance”
    clauses, it is difficult to read the clauses here as a clear and
    explicit direction to adopt a requirement of horizontal
    exhaustion in cases of long-tail injury.
    While the “other insurance” clauses do not speak clearly
    to the question before us, other aspects of the insurance policies
    strongly suggest that the exhaustion requirements were meant
    to apply to directly underlying insurance and not to insurance
    purchased for other policy periods. First and most obviously,
    the excess policies explicitly state their attachment point,
    generally by referencing a specific dollar amount of underlying
    insurance in the same policy period that must be exhausted. For
    example, certain Fireman’s Fund Insurance Company policies
    provide: “It is a condition of this policy that the insurance
    afforded under this policy shall apply only after all underlying
    insurance has been exhausted.” The policies then list the
    “Underlying Insurance Limit of Liability”—for example,
    “$30,000,000 each occurrence $30,000,000 aggregate.” In other
    words, this policy agrees to indemnify Montrose once it has
    exhausted $30 million of underlying insurance. But under the
    insurers’ theory of horizontal exhaustion, Montrose would not
    21
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    be permitted to access this policy until it has exhausted $30
    million of underlying insurance for every relevant policy period—
    which would add up to substantially more than $30 million.
    Indeed, here, where the continuous injury occurred over the
    course of a quarter century, such a rule would increase the
    operative attachment point for this policy from $30 million to
    upwards of $750 million. Thus, where aggregate liability
    amounts to approximately $200 million, Montrose would not be
    able to access an insurance policy that, by its terms, kicks in
    after $30 million of underlying insurance is exhausted.
    Relatedly, the excess policies regularly include or
    reference schedules of underlying insurance—all for the same
    policy period. Under Montrose’s reading, these schedules
    provide a presumptively complete list of insurance coverage that
    must be exhausted before the excess policy may be accessed,
    with the “other insurance” clauses serving as a backstop to
    prevent double recovery in the rare circumstance where
    underlying coverage changes after the excess policy is written.
    (See 
    Dart, supra
    , 28 Cal.4th at p. 1079.) But under the insurers’
    rule of horizontal exhaustion, these schedules would represent
    only a fraction—perhaps only a small fraction—of the insurance
    policies that must be exhausted before a given excess policy may
    be accessed.
    In sum, the “other insurance” clauses do not clearly specify
    whether a rule of horizontal or vertical exhaustion applies here.
    Read in isolation, the “other insurance” clauses might plausibly
    be read to perform the function the insurers ascribe to them.
    But read in conjunction with the actual language of other
    provisions in the policies, and in light of their historical role of
    governing allocation between overlapping concurrent policies,
    22
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    the insurers’ reading becomes less likely. Rather, in the absence
    of any more persuasive indication that the parties intended
    otherwise, the policies are most naturally read to mean that
    Montrose may access its excess insurance whenever it has
    exhausted the other directly underlying excess insurance
    policies that were purchased for the same policy period.
    C.
    To the extent any of the language of these policies remains
    ambiguous, we resolve these ambiguities to protect “ ‘ “ ‘the
    objectively reasonable expectations of the insured.’ ” ’ ”
    
    (Minkler, supra
    , 49 Cal.4th at p. 321.) Consideration of the
    parties’ reasonable expectations favors a rule of vertical
    exhaustion rather than horizontal exhaustion.
    For starters, applying the horizontal exhaustion rule
    would be far from straightforward. The insurers describe the
    rule in simple terms: as a matter of traveling across “layers” of
    stacked “blocks” of excess insurance coverage before the insured
    may travel upwards. But this depiction suggests a degree of
    standardization across policies that does not exist. The policies
    Montrose purchased come in all shapes and sizes, each covering
    different periods of time, providing different levels of coverage,
    and setting forth distinct exclusions, terms, and conditions.
    Given all of these variations across the relevant dimensions,
    how would a rule of horizonal exhaustion apply? If one were to
    stack the excess policies on a graph based on their coverage
    limits or attachment points, the first layer of excess insurance
    in 1984, for example, would appear to reach as high as the 13th
    layer of excess coverage in 1974. To which horizontal layer does
    the 1984 policy belong? The policies do not say. Nor does
    anything in the text of these policies tell us how an “other
    23
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    insurance” clause in a policy from one period ought to apply to a
    policy from another period that contains both a lower
    attachment point and a higher coverage limit. The policies’
    silence on these basic, foundational questions tends to
    undermine the idea the parties expected such a rule to apply.
    But perhaps more importantly, because the exclusions,
    terms, and conditions may vary from one policy to another, a
    rule of horizontal exhaustion would create significant practical
    obstacles to securing indemnification. As the Court of Appeal
    stated in State of California v. Continental Ins. 
    Co., supra
    , 15
    Cal.App.5th at page 1033, “if a lower-layer insurer for a different
    policy period happened to claim that some exclusion in its policy
    applied, a court could not determine whether Continental’s
    policies were triggered without first determining that exclusion
    claim.” Such a rule would put the insured to the considerable
    expense of establishing a right to coverage under the definitions,
    terms, conditions, and exclusions from policies in every policy
    period triggered by the continuous injury. Coverage under less
    restrictive policies would be delayed until more restrictive policy
    terms are adjudicated. In sum, “[h]orizontal exhaustion would
    create as many layers of additional litigation as there are layers
    of policies.” (Westerport Ins. Corp. v. Appleton Papers Inc.
    (Wis.Ct.App. 2010) 
    787 N.W.2d 894
    , 918.) What is more,
    requiring a policyholder to litigate the terms and conditions of
    all policies with lower attachment points in every policy period
    before accessing policies with higher attachment points would
    effectively    increase    the    attachment     point—thereby
    undermining the policyholder’s reasonable expectation that
    coverage would be triggered upon the exhaustion of the amount
    listed as the policy’s stated attachment point. Objectively
    24
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    speaking, the parties could not have intended to require the
    insured to surmount all these hurdles before the insured may
    access the excess insurance it has paid for.
    The insurers counter that the rule of horizontal
    exhaustion is logically compelled by our adoption of an all-sums-
    with-stacking approach to liability for long-tail injuries. They
    argue that if the insured is to have access to all policies across
    all relevant policy periods, it only makes sense that the insured
    must seek indemnification based on its excess coverage across
    all relevant policy periods; to do otherwise, the insurers assert,
    would “artificially break[]” the long-tail injury into distinct
    periods, contrary to our holding in Continental. 
    (Continental, supra
    , 55 Cal.4th at p. 201.) But the insurers’ conclusion does
    not follow. A rule of vertical exhaustion does not restrict the
    insured from accessing excess coverage from other policy periods
    if the terms and conditions are otherwise met; it merely relieves
    the insured of the obligation of establishing whether all of the
    applicable terms and conditions at any given “layer” of excess
    coverage are met before it accesses the next “layer” of coverage.
    There is no evident inconsistency between an all sums approach
    and one that avoids placing this burden on the insured, with its
    associated delays, before the insured may access its excess
    insurance.
    But if horizontal exhaustion imposes a heavy burden on
    the insured, the insurers claim that vertical exhaustion is
    “totally unfair” to them because “decades’ worth of
    environmental damage [could] fall on the shoulders of
    disfavored insurers who happened to provide excess insurance
    . . . during that single unlucky year or two.” This argument is
    not different in kind from arguments we have already
    25
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    considered and rejected in adopting the all-sums-with-stacking
    approach to the coverage of long-tail injuries. (See, e.g.,
    
    Continental, supra
    , 55 Cal.4th at pp. 199–200;
    id. at pp.
    201–
    202.) What we have said in prior cases applies here as well:
    There is no evident unfairness to insurers when their insureds
    incur liabilities triggering indemnity coverage under the
    negotiated policy contract.7 Just as the all-sums-with-stacking
    approach allows the insured “immediate access to the insurance
    it purchased,” so, too, does vertical exhaustion in a continuous
    injury case. (Continental, at p. 201.)
    Equally to the point, nothing about the rule of vertical
    exhaustion requires a single insurer to shoulder the burden of
    indemnification alone. As we explained in the context of
    primary insurance, “the obligation of successive primary
    insurers to cover a continuously manifesting injury is a separate
    issue from the obligations of the insurers to each other.” 
    (Dart, supra
    , 28 Cal.4th at p. 1080.) Even though a rule of vertical
    exhaustion permits Montrose to access excess insurance from
    any given policy period, provided the directly underlying
    insurance has been exhausted, insurers may seek contribution
    from other excess insurers also liable to the insured. The
    exhaustion rule does not alter the usual rules of equitable
    contribution between insurers. An insurer required to provide
    excess coverage for a long-tail injury may lessen its burden by
    seeking reimbursement from other insurers that issued policies
    during the relevant period. Once again, the critical difference
    7
    Whether losses may be partially allocated to the insured
    for policy periods in which the insured chose to self-insure is a
    question not presented here.
    26
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    between a rule of vertical exhaustion and horizontal exhaustion
    thus is not whether a single disfavored excess insurer will be
    made to carry a disproportionate burden of indemnification, but
    instead whether the administrative task of spreading the loss
    among insurers is one that must be borne by the insurer instead
    of the insured. There is no obvious unfairness to insurers from
    a rule that requires them to bear this administrative burden.
    The insurers lean heavily on Community Redevelopment
    Agency v. Aetna Casualty & Surety Co. (1996) 
    50 Cal. App. 4th 329
    , but that case addresses a meaningfully different scenario
    and thus offers no real lessons for resolving the question now
    before us. In Community Redevelopment, a primary insurer
    sought contribution from an excess insurer for defense costs on
    behalf of the insured in a case involving continuous loss. To
    resolve the conflict, the court applied what it termed a
    “horizontal exhaustion rule”; under that rule, the court held, an
    excess insurer in a continuous injury case is not required “to
    ‘drop down’ and provide a defense to a common insured before
    the liability limits of all primary insurers on the risk have been
    exhausted.” (Id. at p. 332.) In adopting that rule, the court
    explained: “Absent a provision in the excess policy specifically
    describing and limiting the underlying insurance, a horizontal
    exhaustion rule should be applied in continuous loss cases
    because it is most consistent with the principles enunciated in
    Montrose [
    I, supra
    , 
    10 Cal. 4th 645
    ]. . . . Under the principle of
    horizontal exhaustion, all of the primary policies must exhaust
    before any excess will have coverage exposure.” (Community
    Redevelopment, at p. 340.)
    This case differs from Community Redevelopment in
    fundamental    respects.       This    case,    unlike   Community
    27
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    Redevelopment, is not a contribution action between primary
    and excess insurers; it is, rather, a coverage dispute between
    excess insurers and their insured. Regardless of whether
    Community Redevelopment was correct to apply a rule of
    horizontal exhaustion in that distinct context—a question not
    presently before us—we are unpersuaded that the reasoning of
    Montrose I requires us to apply a rule of horizontal exhaustion
    that would limit Montrose’s ability to access the excess
    insurance coverage it has paid for.
    In sum, we conclude that in a case involving continuous
    injury, where all primary insurance has been exhausted, the
    policy language at issue here permits the insured to access any
    excess policy for indemnification during a triggered policy period
    once the directly underlying excess insurance has been
    exhausted. Parties to insurance contracts are, of course, free to
    write their policies differently to establish alternative
    exhaustion requirements or coverage allocation rules if they so
    wish. (See 
    Continental, supra
    , 55 Cal.4th at p. 202.)
    D.
    As noted earlier, Travelers opposes Montrose’s motion for
    summary adjudication on two independent grounds. First,
    Travelers argues that Montrose’s requested declaration, which
    would permit Montrose to “seek indemnification” from an excess
    policy upon establishing that “its liabilities are sufficient to
    exhaust the underlying policy(ies) in the same policy period,” is
    directly contrary to the terms of the Travelers policies, which
    require actual exhaustion before a policyholder may access
    excess coverage. Second, Travelers argues that its policies with
    Montrose must be construed under Connecticut or New York
    law, rather than California law as assumed by Montrose’s
    28
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    petition, given Montrose’s principal place of business at the time
    the Travelers policies were issued. The lower court did not reach
    either of these issues because it determined for other reasons
    that Montrose is not entitled to summary adjudication.
    (Montrose I
    I, supra
    , 14 Cal.App.5th at p. 1336, fn. 9.)
    These arguments are not properly before us. We granted
    Montrose’s petition to determine whether Montrose may seek
    coverage from its excess policies under a rule of vertical
    exhaustion rather than horizontal exhaustion. The choice
    between these two rules does not alter any of the remaining
    prerequisites Montrose must satisfy to obtain indemnification,
    including actual exhaustion of directly underlying insurance,
    according to the specific terms of its excess policies. And because
    the lower courts have not addressed the competing claims about
    choice of law, we decline to resolve the matter in the first
    instance. (See Guz v. Bechtel National Inc. (2000) 
    24 Cal. 4th 317
    , 348.) Whether California law governs the construction of
    Montrose’s policies with Travelers is a question for the Court of
    Appeal on remand.
    III.
    California law permits Montrose to seek indemnification
    under any excess policy once Montrose has exhausted the
    underlying excess policies in the same policy period. Montrose
    is not required to exhaust excess insurance at lower levels for
    all periods triggered by continuous injury before obtaining
    29
    MONTROSE CHEMICAL CORPORATION OF CALIFORNIA
    v. SUPERIOR COURT
    Opinion of the Court by Kruger, J.
    coverage from higher level excess insurance in any period. We
    reverse the judgment of the Court of Appeal and remand for
    further proceedings consistent with this opinion.
    KRUGER, J.
    We Concur:
    CANTIL-SAKAUYE, C. J.
    LIU, J.
    CUÉLLAR, J.
    GROBAN, J.
    ELIA, J.*
    BROWN, J.**
    *
    Associate Justice of the Court of Appeal, Sixth Appellate
    District, assigned by the Chief Justice pursuant to article VI,
    section 6 of the California Constitution.
    **
    Associate Justice of the Court of Appeal, First Appellate
    District, Division Four, assigned by the Chief Justice pursuant
    to article VI, section 6 of the California Constitution.
    30
    See next page for addresses and telephone numbers for counsel who argued in Supreme Court.
    Name of Opinion Montrose Chemical Corp. v. Superior Court
    __________________________________________________________________________________
    Unpublished Opinion
    Original Appeal
    Original Proceeding
    Review Granted XXX 
    14 Cal. App. 5th 1306
    Rehearing Granted
    __________________________________________________________________________________
    Opinion No. S244737
    Date Filed: April 6, 2020
    __________________________________________________________________________________
    Court: Superior
    County: Los Angeles
    Judge: Elihu Berle
    __________________________________________________________________________________
    Counsel:
    Latham & Watkins, Brook B. Roberts, John M. Wilson and Drew T. Gardiner for Petitioner.
    Morgan Lewis & Bockius, Michel Y. Horton, Jeffrey S. Raskin, Thomas M. Peterson, Paul A. Zevnik
    and David S. Cox for ITT LLC and Santa Fe Braun, Inc., as Amici Curiae on behalf of Petitioner.
    No appearance for Respondent.
    Gibson, Dunn & Crutcher, Theodore J. Boutrous, Jr., Julian W. Poon, Jeremy S. Smith and Madeleine F.
    McKenna for Real Parties in Interest Continental Casualty Company, Columbia Casualty Company,
    American Centennial Insurance Company and Lamorak Insurance Company.
    Sinnott, Puebla, Campagne & Curet, Kenneth H. Sumner and Lindsey A. Morgan for Real Parties in
    Interest AIU Insurance Company, American Home Assurance Company, Granite State Insurance
    Company, Landmark Insurance Company, Lexington Insurance Company, National Union Fire Insurance
    Company of Pittsburgh, PA, and New Hampshire Insurance Company.
    Sinnott, Puebla, Campagne & Curet, Randolph P. Sinnott, Mary E. Gregory; Cozen O'Conner and John
    Daly for Real Party in Interest Zurich International (Bermuda) Ltd.
    Duane Morris, Max H. Stern and Jessica E. La Londe for Real Party in Interest American Centennial
    Insurance Company.
    Craig & Winkelman and Bruce H. Winkelman for Real Party in Interest Munich Reinsurance America, Inc.
    Selman & Breitman, Ilya A. Kosten, Kelsey C. Start; Barbanel & Treuer and Alan H. Barbanel for Real
    Parties in Interest Transport Insurance Company and Lamorak Insurance Company.
    Selman & Breitman and Elizabeth M. Brockman for Real Party in Interest Federal Insurance Company.
    Berkes, Crane, Robinson & Seal, Steven M. Crane and Barbara S. Hodous for Real Parties in Interest
    Continental Casualty Company and Columbia Casualty Company.
    Lewis Brisbois Bisgaard & Smith, Peter L. Garchie and James P. McDonald for Real Party in Interest
    Employers Mutual Casualty Company.
    Barber Law Group and Bryan M. Barber for Real Party in Interest Employers Insurance of Wausau.
    McCurdy & Fuller, Kevin G. McCurdy and Vanci Y. Fuller for Real Parties in Interest Everest Reinsurance
    Company and MT. McKinley Insurance Company.
    Chamberlin & Keaster, Chamberlin Keaster & Brockman, Kirk C. Chamberlin, Michael
    Denlinger and Kevin J. Schettig for Real Party in Interest Providence Washington Insurance Company.
    Tressler, Linda Bondi Morrison and Ryan B. Luther for Real Party in Interest Allstate Insurance Company.
    Archer Norris, Andrew J. King, GailAnn Y. Stargardter; Tressler and Charles R. Diaz for Real Parties in
    Interest Fireman's Fund Insurance Company and National Surety Corporation.
    Lewis, Brisbois, Bisgaard & Smith, Jordon E. Harriman, Shannon L. Santos; Budd Larner and Michael J.
    Balch for Real Parties in Interest General Reinsurance Corporation and North Star Reinsurance
    Corporation.
    Hinshaw & Culbertson, Thomas R. Beer and Peter J. Felsenfeld for Real Party in Interest Gerling Konzern
    Allgemeine Versicherungs-Aktiengesellschaft.
    O'Melveny & Myers, Richard B. Goetz, Zoheb P. Noorani and Michael Reynolds for Real Party in Interest
    TIG Insurance Company.
    McCloskey, Waring, Waisman & Drury and Andrew McCloskey for Real Party in Interest
    Westport Insurance Corporation.
    Simpson Thacher & Bartlett, Peter R. Jordon, Andrew T. Frankel, Deborah Lynn Stein and Tyler Z.
    Bernstein for Real Parties in Interest Travelers Casualty and Surety Company and The Travelers Indemnity
    Company.
    Covington & Burling, David B. Goodwin, Reynold L. Siemens, Jeffrey A. Kiburtz and Heather W. Habes
    for United Policyholders as Amicus Curiae on behalf of Petitioner.
    Counsel who argued in Supreme Court (not intended for publication with opinion):
    John Wilson
    Latham & Watkins LLP
    12670 High Bluff Drive
    San Diego, CA 92130
    (858) 523-5400
    Theodore J. Boutrous, Jr.
    Gibson, Dunn & Crutcher, LLP
    333 South Grand Avenue
    Los Angeles, CA 90071
    (213) 229-7500