Truck Ins. Exchange v. Kaiser Cement & Gypsum Corp.

IN THE SUPREME COURT OF

CALIFORNIA

TRUCK INSURANCE EXCHANGE,

Plaintiff and Appellant,

v.

KAISER CEMENT AND GYPSUM CORP. et al.,

Defendants, Cross-complainants and Appellants;

LONDON MARKET INSURERS,

Defendant and Appellant;

INSURANCE COMPANY OF THE STATE OF PENNSYLVANIA,

Cross-defendant and Appellant;

GRANITE STATE INSURANCE COMPANY et al.,

Defendants and Respondents.

S273179

Second Appellate District, Division Four

B278091

Los Angeles County Superior Court

BC249550

June 17, 2024

Justice Groban authored the opinion of the Court, in which

Chief Justice Guerrero and Justices Corrigan, Liu, Kruger,

Jenkins, and Evans concurred.

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

S273179

Opinion of the Court by Groban, J.

This appeal requires us to decide when a first-level excess

insurer’s indemnity obligations attach in the context of a

continuous injury that triggers multiple policy periods. In

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

9 Cal.5th 215 (Montrose III),1 we addressed the sequence in

which an insured could access its excess insurance policies for

continuous environmental damage that had occurred over two

decades. The insured sought a rule of “vertical exhaustion,”

which would allow it to access an excess insurance policy as soon

as all the directly underlying insurance from that policy period

(i.e., any primary and any excess policies with a lower

attachment point) were exhausted. (See id. at p. 225.) The

insurer sought a rule of “horizontal exhaustion,” which would

not allow the insured to access an excess policy until it had

exhausted every excess policy with a lower attachment point

across all relevant policy periods. (See ibid.) The parties to

Montrose III did not dispute that all primary policies had been

exhausted. Thus, the only issue before us was whether, upon

exhaustion of all primary policies, the availability of excess

1

Because Montrose Chemical Corp. of California v.

Superior Court (2020) 9 Cal.5th 215, is the third and most recent

decision in a series of cases involving the Montrose litigation,

the Court of Appeal and the parties refer to it as “Montrose III.”

We will use the same short form here.

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

policies was governed by a rule of vertical or horizontal

exhaustion. (See id. at p. 226, fn. 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”].)

This case requires us to resolve the question that we left

open in Montrose III: whether standard language in commercial

general liability policies that are excess to primary insurance

policies should be interpreted to require vertical or horizontal

exhaustion. In other words, can an insured access a first-level

excess insurance policy upon exhaustion of underlying primary

insurance obtained for the same policy period (vertical

exhaustion), or is the insured required to exhaust all primary

policies issued during the continuous period of damage

(horizontal exhaustion)?

The appellant in this case is Truck Insurance Exchange

(Truck), a primary insurer for Kaiser Cement and Gypsum

Corporation (Kaiser). Truck filed an equitable contribution

claim against several insurers that had issued first-level excess

policies to Kaiser for policy years where the directly underlying

primary policy had been exhausted. Relying on our reasoning

in Montrose III, supra, 9 Cal.5th 215, Truck argued that the

excess insurers’ indemnity obligations were triggered

immediately upon exhaustion of the directly underlying primary

policies. Truck further reasoned that because the excess

insurers owed a coverage duty to Kaiser, they were effectively

responsible for indemnifying the same loss as Truck and should

therefore be required to contribute to Truck’s coverage costs.

The excess insurers, however, argued that they had no duty to

indemnify Kaiser until it had exhausted every primary policy

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

issued during the period of continuous damage (including the

policy Truck had issued), and thus there was no possible basis

for contribution. According to the excess insurers, Montrose III’s

analysis is limited to excess policies that sit over other excess

policies, not first-level excess policies that sit over primary

insurance. The Court of Appeal agreed that Montrose III did not

extend to excess policies that sit over primary insurance, which

has characteristics that are distinct from excess insurance

including immediate coverage and defense obligations. In so

ruling, the court rejected SantaFe Braun, Inc. v. Insurance Co.

of North America (2020) 52 Cal.App.5th 19 (SantaFe), which

held that Montrose III’s reasoning does apply in the context of

first-level excess policies. The court further concluded that

because the excess insurers had no coverage obligation under

their policies until all primary insurance had been exhausted

(including Truck’s primary policy), Truck was not entitled to

contribution.

Contrary to the Court of Appeal, we conclude that our

analysis in Montrose III applies equally here. The language of

the first-level excess policies at issue in this case is essentially

identical — and in some cases actually identical — to the policy

language in the higher-level excess policies that we considered

in Montrose III. The policies also share many of the same

characteristics that we found “strongly suggest[ive]” (Montrose

III, supra, 9 Cal.5th at p. 233) of vertical, rather than

horizontal, exhaustion. Thus, as in Montrose III, we believe the

first-level excess policies are most reasonably construed as

requiring only vertical exhaustion.

The excess insurers seem to concede — or at least do little

to dispute — that the language of their policies is substantially

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

identical to the policies at issue in Montrose III. They argue,

however, that such language should be assigned a different

meaning in the current context given the “qualitative

distinctions” between primary and excess insurance.

Specifically, they note that primary insurers generally receive

higher premiums and offer lower liability limits in exchange for

coverage that attaches immediately upon the happening of an

insurable occurrence and provide defense costs. We are not

persuaded that those distinctions justify adopting a different

interpretation of the exact same policy language that we

construed in Montrose III.

Our conclusion that the first-level excess policies only

require vertical exhaustion does not, however, fully resolve the

questions presented in this appeal. Unlike in Montrose III,

which involved an insurance coverage dispute between an

insured and its insurer, this case involves a contribution claim

between coinsurers. While coverage disputes between insureds

and their insurers are a form of contract action that turns on the

meaning of the policy language, “an equitable contribution claim

between coinsurers is not based upon contract, but instead

involves ‘ “equitable principles designed to accomplish ultimate

justice in the bearing of a specific burden.” ’ ” (Axis Surplus Ins.

Co. v. Glencoe Ins. Ltd. (2012) 204 Cal.App.4th 1214, 1227–1228

(Axis), quoting Signal Companies, Inc. v. Harbor Ins. Co. (1980)

27 Cal.3d 359, 369 (Signal).) Although the terms of the relevant

policies are an important factor when deciding whether

contribution is appropriate, courts may consider “a variety of

[other] factors” (Travelers Casualty & Surety Co. v. Century

Surety Co. (2004) 118 Cal.App.4th 1156, 1162), including “ ‘ “the

nature of the claim, the relation of the insured to the insurers

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

. . . and any other equitable considerations.” ’ ” (Truck Ins.

Exchange v. Unigard Ins. Co. (2000) 79 Cal.App.4th 966, 974

(Unigard); see Signal, at p. 369.) Thus, our finding that the

first-level excess policies do not require the insured to

horizontally exhaust primary insurance issued during different

policy periods does not resolve whether Truck is entitled to

contribution from the excess insurers.

In the proceedings below, the excess insurers and Kaiser

argued that even if the policy agreements were, as a matter of

contract interpretation, properly construed as authorizing the

insured (Kaiser) to access its first-level excess insurance upon

exhaustion of the directly underlying primary insurance, it

would nonetheless remain unfair as a matter of equity to allow

a primary insurer to obtain contribution from an excess insurer

given the distinct roles those two types of carriers play in

covering a loss. (See generally Dart Industries, Inc. v.

Commercial Union Ins. Co. (2002) 28 Cal.4th 1059, 1080 (Dart)

[“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”].) They further

contended that ordering contribution would be particularly

unfair under the specific circumstances of this case because it

would effectively allow Truck to pay less insurance than it had

promised to Kaiser, while leaving Kaiser and injured asbestos

claimants with less overall coverage.

Because the Court of Appeal rejected Truck’s contribution

claim based entirely on its erroneous interpretation of the excess

policies (i.e., that the excess insurers had no coverable obligation

under the policies until Kaiser horizontally exhausted all

primary insurance), it did not reach these alternative

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

arguments regarding the fairness of ordering the excess

insurers to contribute to Truck. Having now concluded that the

excess policies require only vertical exhaustion, we remand the

matter to allow the Court of Appeal to address these alternative

arguments in the first instance. (See Hamilton v. Asbestos Corp.

(2000) 22 Cal.4th 1127, 1149 (Hamilton) [“It is appropriate to

remand for the Court of Appeal to resolve . . . in the first

instance” issues that the court chose “not [to] reach because of

its holdings”].)

I. BACKGROUND

From 1944 through the 1970s, Kaiser manufactured

asbestos-containing products at numerous different facilities.

By 2004, more than 24,000 claimants had filed product liability

suits against Kaiser alleging that they had suffered bodily

injury (primarily asbestosis or cancer) as a result of exposure to

Kaiser’s asbestos products. (See London Market Insurers v.

Superior Court (2007) 146 Cal.App.4th 648, 652.) Kaiser

tendered these claims to Truck, one of several primary insurers

that had issued commercial general liability (CGL) policies to

Kaiser during the relevant time period.

In 2001, Truck initiated this insurance coverage action to

determine its indemnity and defense obligations to Kaiser.

Several years later, Truck amended its complaint to add a cause

of action for contribution against several of Kaiser’s excess

insurers. The litigation has generated multiple appellate

decisions that have addressed a wide range of complex questions

regarding insurance coverage and policy interpretation. In this

appeal, we review only one of the issues decided by the Court of

Appeal: Whether Truck is entitled to contribution from various

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

coinsurers that issued first-level excess policies to Kaiser during

the period in question.

A. The All Sums with Stacking Approach to

Continuous Injuries

Before turning to the procedural history of the parties’

current dispute, it is helpful to review general principles of

insurance law that govern “continuous or ‘long-tail’ injury . . .,

where damage occurs over multiple policy periods.” (Montrose

III, supra, 9 Cal.5th at pp. 226–227.) In the context of standard

“occurrence based” CGL insurance policies,2 California has

adopted what is known as the “all-sums-with-stacking”

approach to continuous injuries. This approach has three

primary components. First, in Montrose I, supra, 10 Cal.4th

645, we adopted the “continuous injury trigger of coverage”

principle (id. at p. 685), under which “bodily injury and property

damage that is continuous or progressively deteriorating

throughout several policy periods is potentially covered by all

policies in effect during those periods.” (Id. at p. 655.) In other

2

While the specifics of their language may vary, traditional

“occurrence based” CGL policies generally insure the

policyholder for “ ‘all sums which the insured shall become

legally obligated to pay as damages because of . . . bodily injury,

or . . . property damage to which this insurance applies, caused

by an occurrence.’ ” (Montrose Chemical Corp. v. Admiral Ins.

Co. (1995) 10 Cal.4th 645, 656 (Montrose I); see id. at pp. 669–

670 [discussing drafting history of standardized CGL policy

language].)

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

words, the insured may call upon any policy that was in effect

during the continuous period of injury.3

Second, in Aerojet-General Corp. v. Transport Indemnity

Co. (1997) 17 Cal.4th 38, we adopted “the ‘all sums’ rule” (State

of California v. Continental Ins. Co. (2012) 55 Cal.4th 186, 191

(Continental)), pursuant to which each policy triggered during a

long-tail injury is potentially liable for the total amount of the

loss, regardless of whether a portion of the loss occurred outside

the policy’s coverage period. The rule “envisions that each

successive insurer is potentially liable for the entire loss up to

its policy limits. When the entire loss is within the limits of one

policy, the insured can recover from that insurer, which may

then seek contribution from the other insurers on the risk

during the same loss.” (Id. at p. 200.)

Third, in Continental, supra, 55 Cal.4th 186, we construed

language in standard CGL policies to permit “stacking,” which

allows an insured “to add together the maximum limits of all

consecutive policies that [were] in place during the [period of

continuous injury].” (12 Couch on Insurance (3d ed. 2010)

§ 169:5; see Continental, at p. 200 [“ ‘stacking’ generally refers

to the stacking of policy limits across multiple policy periods

that were on a particular risk”].) In other words, “ ‘[w]hen the

3

In Armstrong World Industries, Inc. v. Aetna Casualty &

Surety Co. (1996) 45 Cal.App.4th 1, the court held that asbestos-

related bodily injury claims qualify as a form of continuing

injury that triggers all policies “ ‘in effect from [the claimant’s]

first exposure to asbestos or asbestos-containing products until

date of death or date of claim, whichever occurs first[.]’ ” (Id. at

p. 43.) The parties appear to assume (at least for the purposes

of this appeal) that Armstrong states the proper trigger rule for

asbestos-related injury claims. We will do the same.

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

policy limits of a given insurer are exhausted, [the insured] is

entitled to seek indemnification from any of the remaining

insurers [that were] on the risk [during the continuous period of

injury].’ ” (Continental, at p. 200.) If, for example, an insured

purchased 10 annual policies that each had a coverage limit of

$1 million, and all the policies were triggered by a continuous

injury, the insured would be permitted to stack all of the policies

to collect up to $10 million in total coverage. (See id. at p. 201

[the “all-sums-with-stacking indemnity principle . . . ‘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’ ”].)

In adopting this all-sums-with-stacking approach,

however, we have cautioned that “future . . . contracting parties

can write into their policies whatever language they agree upon,

including limitations on indemnity, equitable pro rata coverage

allocation rules, and prohibitions on stacking.” (Continental,

supra, 55 Cal.4th at p. 202.)

B. Summary of Kaiser’s Insurance Policies

Having summarized general principles of insurance law

relating to continuous injuries, we turn now to the specific facts

at issue in this appeal. During the relevant time period, Kaiser

purchased primary and excess CGL insurance from numerous

different insurers. “Primary insurance refers to the first layer

of coverage, whereby ‘liability attaches immediately upon the

happening of the occurrence that gives rise to liability.’ ”

(Montrose III, supra, 9 Cal.5th at p. 222.) “Primary insurers

generally have the primary duty of defense.” (Olympic Ins. Co.

v. Employers Surplus Lines Ins. Co. (1981) 126 Cal.App.3d 593,

597.) “Excess insurance, by contrast, ‘refers to indemnity

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

coverage that attaches upon the exhaustion of underlying

insurance coverage for a claim.’ [Citation.] 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.” (Montrose III, at pp. 222–223.)

Kaiser’s primary insurers included Fireman’s Fund

Insurance Company (Fireman’s Fund) (1947–1964), Truck (1964

to 1983), Home Insurance Company (1983–1985) and National

Union Fire Insurance Company (1985–1987). The primary

policy that Truck issued for the 1974–1975 period provided a

“per occurrence” limit of $500,000, meaning that Truck would

provide up to $500,000 of coverage for each claim alleging

injurious exposure to asbestos. However, the policy did not

include any aggregate limit of coverage. In contrast, all the

primary policies issued by non-Truck insurers did contain an

aggregate limit on coverage.

Kaiser also obtained first-level excess policies from

multiple insurers. The first-level excess policies that are the

subject of Truck’s contribution claim were issued for policy years

in which Truck was not the primary insurer. London Market

Insurers (LMI) provided first-level excess policies during the

years that Fireman’s Fund was the primary insurer (1947 to

1964), while First State (1983–1984) and Westchester Fire

(1984–1985) each provided a first-level excess policy during the

years that Home Insurance Company was the primary insurer.

Each of the first-level excess policies include language

stating that coverage will not attach until Kaiser has exhausted

underlying primary policies that are listed in a schedule of

underlying insurance. The policies require Kaiser to maintain

those scheduled primary policies during the relevant period of

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TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

coverage. Each excess policy also includes an “other insurance”

provision that states, in a variety of ways, that the insured must

also exhaust any “other insurance” or “other underlying

insurance” before the excess policy can be accessed.4

C. Procedural History

Kaiser assigned all asbestos-related bodily injury claims

that triggered Truck’s 1974 primary policy — which presumably

includes any claims alleging that the claimant’s initial exposure

to asbestos occurred in or before 1974 (see ante, p. 8, fn. 3) — to

the 1974 policy. According to the excess insurers, Kaiser

selected Truck’s 1974 policy because it “has no aggregate limit,

does not require Kaiser to pay an allocated share of defense (like

Truck’s other primary policies), and . . . has the lowest

deductible per occurrence ($5,000).” Truck subsequently

entered into agreements with the other primary insurers to

share defense and indemnity costs.

1. Kaiser Cement and Gypsum Corp. v. Insurance

Co. of Pennsylvania (Apr. 8, 2013, B222310)

(nonpub. opn.)

Truck initiated this litigation in 2001 to determine its

coverage obligations to Kaiser. In a prior appeal, Kaiser Cement

and Gypsum Corp. v. Insurance Co. of Pennsylvania (Apr. 8,

2013, B222310) (review den. and opn. ordered nonpub. July 17,

2013) (Kaiser Cement), the Court of Appeal decided two issues

4

The specific wording of these “other insurance” clauses is

explored in more detail below.

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

that have relevance to the current dispute.5 First, the court held

that Kaiser could not access a 1974 first-level excess policy that

sat over Truck’s 1974 primary policy until Kaiser had

horizontally exhausted every primary policy issued during the

claimant’s period of continuous damage. In support, the court

relied on language in the excess policy stating that the insurer’s

indemnity obligations would attach upon exhaustion of Truck’s

1974 primary insurance plus the “ ‘ “applicable limit(s) of any

other underlying insurance collectible by the insured.” ’ ”

(Italics omitted.) Following the reasoning of Community

Redevelopment Agency v. Aetna Casualty & Surety Co. (1996)

50 Cal.App.4th 329 (Community Redevelopment) — a case we

discuss in more detail below — the court explained that the

“policy’s reference to ‘any other underlying insurance’

necessarily means ‘whatever’ . . . primary insurance is available

to Kaiser — not, as Kaiser suggests, only that primary

insurance that expressly covers the 1974 policy year.”

Second, the court ruled that Truck’s 1974 primary policy

included an anti-stacking provision that prohibited Kaiser from

obtaining coverage from any of the other primary policies Truck

had issued between 1964 and 1983. Although the court

acknowledged that insureds are generally permitted to stack

successive policies (see Continental, supra, 55 Cal.4th at p. 200;

ante, at pp. 8–9), it reasoned that Truck’s 1974 policy contained

language that expressly prohibited Kaiser from receiving

5

An unpublished decision may be cited “[w]hen the opinion

is relevant under the doctrines of law of the case, res judicata,

or collateral estoppel.” (Cal. Rules of Court, rule 8.1115(b)(1).)

Kaiser Cement is relevant here as law of the case and we cite it

solely for that reason.

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AND GYPSUM CORP.

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indemnification from any other policy that Truck had issued. As

a result of the court’s ruling, Truck’s total indemnity obligation

for each asbestos claim triggering the 1974 policy was only

$500,000, which was substantially less than the $8.3 million per

claim that the excess insurers allege Truck would have been

obligated to pay if Kaiser was allowed to stack all 19 of its Truck

policies. In subsequent litigation, it was determined that all

primary policies issued by non-Truck insurers had been

exhausted as of 2004.

Thus, the Kaiser Cement decision had two important

effects on the insurance coverage litigation. First, the court’s

interpretation of the “other insurance” provision in Kaiser’s

1974 first-level excess policy effectively precluded Kaiser from

accessing any of its excess insurance until it had exhausted

every primary policy issued during the period of continuous

injury. Second, Kaiser could not obtain coverage from any of the

primary policies that Truck had issued other than the 1974

policy. As a result of those rulings, and the subsequent

exhaustion of all primary policies that had been issued by non-

Truck insurers, Truck’s 1974 policy is currently the only

primary insurance that remains available to Kaiser for any

asbestos-related bodily injury claim alleging initial exposure in

or before the 1974–1975 policy period. As noted, that policy

requires Truck to provide up to $500,000 for each asbestos claim,

with any amounts exceeding that level going to excess

insurance. Following Kaiser Cement, various excess insurers

entered into an agreement with Kaiser regarding the funding of

the excess portion of any individual claims that exceed Truck’s

$500,000 obligation.

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2. Current litigation

At some point after it was determined that Truck’s 1974

policy was the only remaining primary insurance (but before we

had decided Montrose III), Truck filed the current equitable

contribution claim against each of the first-level excess insurers

that sit above the now-exhausted primary policies that were

issued by non-Truck insurers. Presenting arguments that are

substantially similar to those that Kaiser had raised in Kaiser

Cement, Truck argued that the first-level excess insurers’

indemnity obligations to Kaiser attached upon exhaustion of the

directly underlying primary policies. Truck further contended

that because the excess insurers’ coverage obligations had been

triggered, they should be ordered to “contribute to Truck’s

indemnity and defense obligations under the 1974 policy.” The

excess insurers, however, argued there was no basis for

contribution because all of the applicable excess policies

contained “other insurance” provisions that conditioned

coverage on the exhaustion of all available underlying primary

insurance that had been issued during the continuous period of

damage, which necessarily included Truck’s 1974 primary

policy.

Following a bench trial in 2016, the trial court issued an

order denying Truck’s contribution request. Citing Community

Redevelopment, supra, 50 Cal.App.4th 329, and the Kaiser

Cement decision previously issued in this litigation (see ante, at

pp. 11–13), the trial court agreed with the excess insurers that

the “other insurance” provisions in the first-level excess policies

called for horizontal exhaustion of all primary insurance,

including Truck’s 1974 primary policy. The trial court further

reasoned that because the excess insurers’ policies did not

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

attach until Truck’s 1974 primary policy was exhausted, there

was no possible basis for Truck to receive contribution.

While Truck’s appeal of the order denying contribution

was pending, we issued our decision in Montrose III, supra,

9 Cal.5th 215. As discussed in more detail below, Montrose III

held that an insured’s excess insurance policies required only

vertical exhaustion, meaning that the insurers’ indemnity

obligations attached as soon as the insured had exhausted any

excess policies with lower attachment points that had been

issued for the same policy year. In reaching that conclusion, we

rejected the excess insurers’ contention that the policies’ “other

insurance” provisions required horizontal exhaustion of all

excess policies with lower attachment points that had been

issued during the period of continuous injury.

On appeal, Truck argued that Montrose III’s

interpretation of “other insurance” policies had effectively

rejected (and overruled) the Court of Appeal’s analysis in

Community Redevelopment and Kaiser Cement. Truck noted

that a recent appellate decision, SantaFe, supra, 52 Cal.App.5th

19, had reached exactly that conclusion in a coverage dispute in

which the insured had sought access to a first-level excess policy

immediately upon exhaustion of the directly underlying primary

policy. The SantaFe court held that Community Redevelopment

and other decisions that had embraced horizontal exhaustion

based on “other insurance” provisions had “rel[ied] on an

interpretation of policy language rejected by the Supreme Court

in Montrose III.” (SantaFe, at p. 30.)

The Court of Appeal, however, disagreed with Truck and

expressly rejected SantaFe’s application of Montrose III. In the

court’s view, Montrose III’s interpretation of “other insurance”

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AND GYPSUM CORP.

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provisions was limited to situations involving “multiple layers

of excess insurance” and had no application to “layers of primary

and excess insurance.” In support, the court noted the

“qualitative[]” distinctions between primary and excess

insurance. According to the court, whatever effect “other

insurance” clauses might have in other contexts, for purposes of

first-level excess policies that sit over primary insurance, such

provisions were most reasonably construed to include any

primary policies that had been issued during the relevant period

of continuous injury.

Having concluded that the first-level excess insurers did

not owe Kaiser any indemnity obligation until Kaiser had

exhausted every primary policy issued during the period of

continuous damage, the court concluded there was no possible

basis to award Truck contribution. We granted review.

II. DISCUSSION

A. Summary of Applicable Law

We begin our analysis by summarizing legal principles

and prior decisional law that relate to the complex questions of

insurance coverage presented in this appeal.

1. Insurance coverage actions versus contribution

action

We have previously distinguished between two forms of

insurance disputes: insurance coverage actions, which typically

involve a dispute between an insured and an insurer regarding

the insurer’s indemnity and defense obligations, and equitable

contribution claims, in which one insurer seeks recovery from

another insurer that allegedly covered the same risk and failed

to pay its proportionate share. (See, e.g., Dart, supra, 28 Cal.4th

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at p. 1080 [“the obligation of successive . . . insurers to cover a

continuously manifesting injury is a separate issue from the

obligations of the insurers to each other. . . . ‘[A]pportionment

among multiple insurers must be distinguished from

apportionment between an insurer and its insured’ ”].)

Insurance coverage claims between an insured and its

insurer are a form of contract dispute and thus focus on “the

language of the insurance policies at issue.” (Montrose III,

supra, 9 Cal.5th at pp. 229–230.) “ ‘ “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

objectively reasonable expectations of the insured.” ’ ” ’

[Citation.] If these rules do not resolve an ambiguity, we may

then ‘ “resort to the rule that ambiguities are to be resolved

against the insurer.” ’ ” (Id. at p. 230, bracketed text in

original.) “ ‘Because the insurer writes the policy, it is held

“responsible” for ambiguous policy language, which is therefore

construed in favor of coverage.’ ” (Montrose I, supra, 10 Cal.4th

at p. 667.)

“[A]n equitable contribution claim between coinsurers[, in

contrast,] is not based upon contract, but instead involves

‘ “equitable principles designed to accomplish ultimate justice in

the bearing of a specific burden” ’ ” (Axis, supra,

204 Cal.App.4th at pp. 1227–1228, quoting Signal, supra,

27 Cal.3d at p. 369.) “In the insurance context, the right to

contribution arises when several insurers are obligated to

indemnify or defend the same loss or claim, and one insurer has

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AND GYPSUM CORP.

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paid more than its share of the loss or defended the action

without any participation by the others. . . . The purpose of this

rule of equity is to accomplish substantial justice by equalizing

the common burden shared by coinsurers, and to prevent one

insurer from profiting at the expense of others.” (Fireman’s

Fund Ins. Co. v. Maryland Casualty Co. (1998) 65 Cal.App.4th

1279, 1293 (Fireman’s Fund).)

Under California law, there is no “definitive rule” that

governs equitable contribution. (Signal, supra, 27 Cal.3d at

p. 369.) Rather, when evaluating a contribution claim, courts

should consider a variety of factors, including “the particular

policies of insurance, the nature of the claim made, . . . the

relation of the insured to the insurers” (ibid.) and “ ‘any other

equitable considerations.’ ” (Unigard, supra, 79 Cal.App.4th at

p. 974.) Although equitable contribution claims are not

“ ‘controlled by the language of [the insurers’] contracts with the

respective policy holders’ ” (Signal, at p. 369), we have

emphasized that the policy language nonetheless remains an

important factor. (See ibid. [courts should not impose

contribution on an insurer that “contraven[es] . . . the provisions

of its policy” absent “some compelling equitable consideration”];

Unigard, at p. 978.) As explained by one court, “if [an] insurer

never had an obligation to provide coverage, it would be

extremely unfair to enforce a contribution action.” (Axis, supra,

204 Cal.App.4th at p. 1228.)

2. Contribution between primary and excess insurers

In the context of traditional “noncontinuous injury”

insurance claims — meaning a claim that implicates only a

single policy period — it has long been the rule that there is “no

contribution between a primary and excess carrier without a

18

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

specific agreement to the contrary.” (Reliance Nat. Indemnity

Co. v. General Star Indemnity Co. (1999) 72 Cal.App.4th 1063,

1080; see Fireman’s Fund, supra, 65 Cal.App.4th at p. 1294,

fn. 4.) The basis for that rule is rooted in the purpose of

contribution, which is to “equaliz[e] the common burden”

(Fireman’s Fund, at p. 1293) shared by coinsurers that “share

the same level of liability on the same risk as to the same

insured.” (Maryland Casualty Co. v. Nationwide Mutual Ins.

Co. (2000) 81 Cal.App.4th 1082, 1089 (Maryland); see Morgan

Creek Residential v. Kemp (2007) 153 Cal.App.4th 675, 684

[contribution applies only when there is a “ ‘common burden of

liability’ ”].) When a claim implicates only a single policy period,

and an excess policy provides that the insurer’s coverage

obligations attach upon exhaustion of the primary insurance

listed in the schedule of underlying insurance, the excess and

primary insurer cannot be said to “share the same level of

liability.” (Maryland, at p. 1089.)

That analysis becomes more complicated in the context of

continuous injuries, which extend over multiple policy periods.

In that circumstance, the question arises whether the excess

insurers’ indemnity obligations to the insured attach: (1) only

after the exhaustion of all primary layers of insurance issued

during the continuous period of injury (horizontal exhaustion);

or (2) whether attachment occurs upon exhaustion of the

directly underlying primary insurance that was issued during

the same policy year (vertical exhaustion). If the excess insurers

have no coverage obligation until all primary policies have

exhausted (horizontal exhaustion), it follows that the excess

insurer cannot be said to be on the same level of liability as any

of the primary insurers, thus precluding any basis for

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TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

contribution between the two types of insurers. In effect,

horizontal exhaustion results in the same situation between

excess and primary insurers that occurs where a claim

implicates only one policy period: the excess insurer and

primary insurer remain on distinct levels of liability, with the

excess insurer’s obligations being triggered only after the

primary coverage is exhausted, thus precluding contribution.

Under vertical exhaustion, however, the excess insurer

owes an indemnity obligation to the insured as soon as the

directly underlying primary policy has exhausted. That is true

even if primary insurance issued for a precedent or subsequent

policy period remains unexhausted (and thus available to the

insured). Thus, unlike the situation with horizontal exhaustion,

under a rule of vertical exhaustion, a first-level excess insurer

from one policy period and a primary insurer from a different

policy period might simultaneously owe coverage to the same

insured for the same injury. In that situation, it becomes less

clear that the excess insurer remains on a different “level of

liability” (Maryland, supra, 81 Cal.App.4th at p. 1089) than

primary insurers that issued unexhausted policies during

different periods of the continuous injury.

Prior to our decision in Montrose III, supra, 9 Cal.5th 215,

the leading case addressing contribution between primary and

excess injuries in the continuous injury context was Community

Redevelopment, supra, 50 Cal.App.4th 329. The insured in

Community Redevelopment obtained annual primary policies

from United between 1982–1985. For the 1985–1986 period, the

insured obtained a primary policy from State Farm and a first-

level excess policy from Scottsdale. The Scottsdale policy stated

that its indemnity obligations would attach upon exhaustion of

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TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

the underlying State Farm policy “ ‘plus the applicable limits of

any other underlying insurance collectible by the insured.’ ” (Id.

at p. 335, italics and capitalization omitted.)

State Farm entered a settlement on behalf of the insured

that exhausted the limits of its 1985–1986 primary policy.

United thereafter brought a contribution action against

Scottsdale, contending “that Scottsdale had a duty to . . .

contribute to the primary coverage burden as soon as State

Farm’s underlying primary policy was exhausted. According to

United, Scottsdale’s policy was expressly excess to State Farm’s

policy; as soon as the latter was exhausted, Scottsdale’s duty

arose and the existence of other primary coverage was

irrelevant.” (Community Redevelopment, supra, 50 Cal.App.4th

at p. 337.)

The court rejected that argument, explaining that “[i]t is

settled under California law that an excess or secondary policy

does not cover a loss, nor does any duty to defend the insured

arise, until all of the primary insurance has been exhausted.”

(Community Redevelopment, supra, 50 Cal.App.4th at p. 339.)

In support, the court cited case law that addressed excess

coverage in the context of noncontinuous injury claims (i.e.,

injuries that triggered only one policy period). The courts in

those cases ruled that first-level excess policies containing

“other insurance” provisions required not only the exhaustion of

the primary insurance expressly listed in the excess policy, but

also any other primary insurance the insured had obtained for

that period. (See ibid.)

The Community Redevelopment court concluded that

“other insurance” provisions should apply the same way in the

context of a continuous injury that triggers multiple policy

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

periods. According to the court, the “other insurance” provision

in Scottsdale’s excess policy made clear that the coverage was

purchased “as excess to the . . . primary policy issued by State

Farm” and “ ‘any other underlying insurance collectible by the

[insured parties].’ ” (Community Redevelopment, supra,

50 Cal.App.4th at p. 338, italics omitted.) In the court’s view,

“[t]he only reasonable interpretation of this policy language is

that the term ‘underlying insurance’ must be read to include all

available primary insurance, not just the policy expressly listed

on the schedule of underlying insurance.” (Id. at p. 341.) The

court reasoned that because Scottsdale’s excess policy called for

horizontal exhaustion of all primary insurance, Scottsdale

remained on a different level of liability than United’s primary

policy, thus precluding contribution.

As noted above, the Court of Appeal in this case (and in its

prior Kaiser Cement decision) chose to follow the reasoning of

Community Redevelopment, concluding both that: (1) the “other

insurance” provisions unambiguously compelled a rule of

horizontal exhaustion; and (2) because the first-level excess

insurers owed no coverage obligation to the insured until all

primary insurance had exhausted, there was no possible basis

for Truck to obtain contribution.6

6

Although the Court of Appeal’s decision denying

contribution in the instant matter did not rely on its prior ruling

regarding horizontal exhaustion set forth in the Kaiser Cement

appeal, the excess insurers nonetheless contend that Kaiser

Cement’s ruling on horizontal exhaustion is now “law of the

case” and cannot be relitigated here. The law of the case

doctrine generally “precludes a party from obtaining appellate

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

3. Montrose III

In Montrose III, supra, 9 Cal.5th 215, we addressed the

application of “other insurance” provisions in the context of

excess policies issued during successive periods of a continuous

injury. The insured was sued for causing continuous

environmental contamination between 1947 and 1982. During

that period, the insured obtained annual policies for primary

insurance and multiple layers of excess insurance. The parties

stipulated that all primary insurance had been exhausted. The

question we had to decide was “the sequence in which [the

insured could] access the excess insurance policies covering this

period.” (Id. at p. 222.) The insured sought a rule of vertical

exhaustion, which would allow it to access an excess insurance

policy upon the exhaustion of any excess policies with lower

attachment points that had been issued for the same policy

review of the same issue more than once in a single action.”

(Katz v. Los Gatos-Saratoga Joint Union High School Dist.

(2004) 117 Cal.App.4th 47, 62.) It is well-settled, however, that

the doctrine may be disregarded where the “controlling rules of

law have been altered or clarified by a decision intervening

between the first and second appellate determinations.” (People

v. Stanley (1995) 10 Cal.4th 764, 787.) Even assuming that

application of law of the case would otherwise be appropriate,

we are satisfied — as apparently was the Court of Appeal —

that our intervening decision in Montrose III, supra, 9 Cal.5th

215, justifies departure from the doctrine here.

We also find no merit in the excess insurers’ contention

that various arguments and admissions Truck made in the

Kaiser Cement appeal regarding the anti-stacking issue

judicially estop Truck from now arguing that under Montrose

III, supra, 9 Cal.5th 215, the first-level excess policies should be

construed as attaching upon exhaustion of the directly

underlying primary policy.

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

period. The insurer sought a rule of horizontal exhaustion,

which would not allow the insured to access an excess policy

until it had exhausted every excess policy with a lower

attachment point that had been issued during the continuous

period of injury. (See id. at p. 229.)

The dispute centered on the meaning of “other insurance”

clauses in the excess insurance policies. Those clauses provided,

in varying ways, that the policies shall be excess to “other

insurance” or “ ‘other underlying insurance’ ” (Montrose III,

supra, 9 Cal.5th at pp. 224–225, italics omitted) available to the

insured, “whether or not the other insurance is specifically listed

in the policy’s schedule of underlying insurance.” (Id. at p. 230.)

Citing Community Redevelopment, supra, 50 Cal.App.4th 329,

the insurers argued that the “other insurance” clauses “call[ed]

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.” (Montrose III, at p. 230.) The insureds, however,

argued that the “other insurance” clauses were intended to refer

only to “other insurance” policies with lower attachment points

that were in effect during the same policy period as the

overlaying excess policy. (See id. at pp. 230–231.)

While finding that both parties had offered reasonable

interpretations of the “other insurance” provisions (see Montrose

III, supra, 9 Cal.5th at pp. 230, 234), we ultimately concluded

that when read “in light of background principles of insurance

law, and considering the reasonable expectations of the parties”

(id. at p. 222), the policy language was “most naturally read to

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

mean that [the insured] may access its excess insurance

whenever it has exhausted the other directly underlying excess

insurance policies that were purchased for the same policy

period” (id. at p. 234).

Turning first to the text of the “other insurance”

provisions, we found that certain characteristics weighed

against the excess insurers’ assertion that such language

unambiguously mandated a rule of horizontal exhaustion.

First, none of the policies contained any language “clearly or

explicitly stat[ing] that [the insured] must exhaust insurance

with lower attachment points purchased for different policy

periods.” (Montrose III, supra, 9 Cal.5th at p. 230.) Second, we

noted that some formulations of the “other insurance” clauses

included broad language that, “[i]f . . . read to apply to

insurance purchased for other policy periods, . . . 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.”

(Id. at p. 231.) Third, we explained that contrary to the excess

insurers’ proposed interpretation, our prior decisions (and the

decisions of several other jurisdictions) made clear that “other

insurance” provisions “have not traditionally been used to

address questions concerning the obligation of successive

insurers to indemnify policyholders for a continuously

manifesting injury.” (Id. at p. 232.) Instead, such clauses have

historically been understood to “address ‘[a]llocation questions

with respect to overlapping concurrent policies.’ ” (Ibid.)

Looking next to the text of the excess policies as a whole,

we found that “other aspects of the insurance policies strongly

25

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

suggest[ed] that the exhaustion requirements were meant to

apply to directly underlying insurance and not to insurance

purchased for other policy periods.” (Montrose III, supra,

9 Cal.5th at p. 233.) First, we noted that many of the 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.” (Ibid.) We explained

that under the “insurers’ theory of horizontal exhaustion,” there

would be no coverage until the insured had exhausted that

attachment amount “for every relevant policy period” (ibid.),

thus substantially increasing the “operative attachment point”

well beyond what the terms of the policy suggested.

Second, and “[r]elatedly” (Montrose III, supra, 9 Cal.5th at

p. 234), we noted that the excess policies “regularly include or

reference schedules of underlying insurance — all for the same

policy period” (ibid.). We explained that under the insured’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. [Citation.] 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.” (Ibid.)

Looking beyond the language of the parties’ policies, we

further concluded that “[c]onsideration of the parties’

reasonable expectations favors a rule of vertical exhaustion

rather than horizontal exhaustion.” (Montrose III, supra,

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TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

9 Cal.5th at p. 234.) First, we noted that “applying the

horizontal exhaustion rule would be far from straightforward”

given the lack of “standardization” between the excess policies

on issues such as attachment points, level of coverage and

specific terms and conditions. (Ibid.) To illustrate the

complexity, we noted that “the first layer of excess insurance in

1984 . . . 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 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.” (Id. at p. 235.)

We also noted that because “exclusions, terms, and

conditions may vary from one policy to another, a rule of

horizontal exhaustion would create significant practical

obstacles to securing indemnification. . . . 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.’ ” (Montrose III, supra, 9 Cal.5th at p. 235.)

We rejected the excess insurers’ contention that a rule of

vertical exhaustion would frustrate the parties’ reasonable

expectations by unfairly requiring “a single insurer to shoulder

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TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

the burden” of indemnifying “ ‘decades’ worth of environmental

damage.’ ” (Montrose III, supra, 9 Cal.5th at p. 236.) We noted

that this argument was “not different in kind from arguments

we have already considered and rejected in adopting the all-

sums-with-stacking approach to the coverage of long-tail

injuries” (ibid.), explaining that “[t]here is no evident unfairness

to insurers when their insureds incur liabilities triggering

indemnity coverage under the negotiated policy contract” (ibid.).

We further explained that a rule of vertical exhaustion “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.”

(Ibid.)

We also rejected the insurers’ reliance on Community

Redevelopment, supra, 50 Cal.App.4th 329, explaining that a

contribution action between a primary insurer and an excess

insurer presented “a meaningfully different scenario” than a

coverage action between an insured and its excess insurers, and

thus “offer[ed] no real lessons for resolving the question now

before us.” (Montrose III, supra, 9 Cal.5th at p. 237.) In a

footnote, we emphasized that because the question had not been

presented, we need not “decide when or whether an insured may

access excess policies before all primary insurance covering all

relevant policy periods has been exhausted.” (Id. at p. 226,

fn. 4.)

B. Analysis

As in Montrose III, we are faced with questions regarding

whether language in standard CGL excess insurance policies

impose a rule of vertical or horizontal exhaustion in the context

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

of continuous injury insurance claims. The Court of Appeal

concluded that because the excess policies at issue in this case

sat above primary insurance, they were most reasonably

construed as requiring the insured (Kaiser) to horizontally

exhaust all primary insurance, including Truck’s 1974 policy.

The court further reasoned that because the excess policies did

not create any coverage obligation until Truck’s policy was

exhausted, there was no possible basis for Truck to receive

contribution.

Given that the court’s contribution analysis turns entirely

on its interpretation of the first-level excess policies, we will

begin our review by assessing the court’s construction of those

contracts, which is “a question of law” to which we apply

independent review. (E.M.M.I. Inc. v. Zurich American Ins. Co.

(2004) 32 Cal.4th 465, 470.)7

7

The excess insurers argue that because this case involves

a claim for equitable contribution, we should apply an abuse of

discretion standard of review. While it is true that our courts

have applied a deferential standard to some aspects of equitable

contribution awards that are not at issue in this case (such as

the trial court’s chosen method for allocating a loss among

insurers), the Court of Appeal’s interpretation of the excess

policies remains a question of law to which we apply de novo

review. (Compare Fireman’s Fund, supra, 65 Cal.App.4th at

p. 1308 [“trial court’s determination of the correct allocation

[method] . . . for purposes of contribution” is reviewed for abuse

of discretion] with Truck Ins. Exchange v. AMCO Ins. Co. (2020)

56 Cal.App.5th 619, 629 [applying de novo review where

contribution claim turned on interpretation of insurance

policies]; Certain Underwriters at Lloyds, London v. Arch

Specialty Ins. Co. (2016) 246 Cal.App.4th 418, 429 [“Although

equitable contribution may call for judicial discretion, here the

29

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

1. The Court of Appeal erred in interpreting the

policy language

As was the case in Montrose III, the Court of Appeal’s

interpretation of the excess policies centered on the meaning of

the “other insurance” clauses in the excess insurance policies.

The text of those clauses are as follows:

• The LMI policies in effect from 1953–1958 provide that

liability shall attach only after the primary insurers

listed in the schedule of underlying insurance have paid

“the full amount of their respective ultimate loss,” and

then define “ultimate net loss” as “the sums paid in

settlement of losses for which the Assured is liable after

making deductions for all recoveries, salvages and

other insurances (other than recoveries under the

policy/ies of the [scheduled primary insurers]), whether

recoverable or not” (italics added);

• The LMI policies in effect from 1958–1964 include an

independent “Other Insurance” clause that provides:

“If other valid and collectible insurance with any other

insurer is available to the Assured 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 other insurance”;

• The First State policy in effect from 1983–1984

provides that the Company shall be liable for loss in

excess of “an amount equal to the limits of liability

trial court expressly stated it decided the matter as a question

of law, and our review is de novo”].)

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TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

indicated beside the underlying insurance listed in the

Schedule A of underlying insurance, plus the applicable

limits of any other underlying insurance collectible by

the insured”; “[i]f other collectible insurance with any

other insurer is available to the insured covering in loss

covered here [sic], except insurance purchased to apply

in excess of the sum of [this policy], the insurance

hereunder shall be in excess of and not contribute with

such other insurance” (italics added).8

Following the analysis in Community Redevelopment,

50 Cal.App.4th 329, the court interpreted these “other

insurance” provisions as unambiguously requiring Kaiser to

exhaust all primary policies that it had purchased for every

policy period triggered by the continuous injury. Truck,

however, contends that our core holding in Montrose III — that

standard “other insurance” provisions appearing in excess

policies are only intended to refer to insurance purchased for the

same policy period — applies equally in the context of excess

policies that sit over primary insurance. As discussed in more

detail below, we agree with Truck that the policy language at

issue here cannot be meaningfully distinguished from the

policies that we addressed in Montrose III. We also agree that

the qualitative distinctions between primary and excess

insurance do not justify assigning an entirely different meaning

to standardized “other insurance” clauses merely because the

excess policy sits over primary insurance rather than another

level of excess insurance.

8

The Westchester policy in effect from 1984–1985 includes

language that is essentially identical to the First State policy.

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TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

The Court of Appeal made no attempt to differentiate the

text of the “other insurance” provisions at issue here and those

at issue in Montrose III. Nor have the excess insurers attempted

to do so in their briefing. That is not particularly surprising

given that the provisions are substantially identical, and in

several formulations exactly identical,9 each providing in

various ways that the excess policy shall be excess to the

underlying primary policy identified in the schedule of

underlying insurance along with any “other insurance” or “other

underlying insurance” available to the insured. As in Montrose

III, none of the provisions explicitly reference “other insurance”

purchased for different policy periods.

Our observations in Montrose III regarding the historical

use of “other insurance” provisions also weigh against the excess

9

For example, one of formulations at issue in Montrose III

provided 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.’ ” (Montrose III, supra, 9 Cal.5th at

pp. 224–225.) Several of the LMI policies at issue in this case

include an identically worded provision. (See ante, at p. 30.) A

second formulation in Montrose III defined the excess insurer’s

attachment point as the total of the liability limits set forth in

the excess policy listed in the schedule of underlying insurance

plus “ ‘the applicable limits of any other underlying insurance

collectible by the insured.’ ” (Montrose III, at p. 224.) The First

State policy at issue in this case likewise defines the attachment

point as the total of the liability limit set forth in the primary

policy listed in the schedule of underlying insurance plus “the

applicable limits of any other underlying insurance collectible by

the insured.” (See ante, at pp. 30–31.)

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

insurers’ contention that such language is most reasonably

interpreted as requiring the insured to exhaust primary

insurance that was issued during precedent or successive policy

periods of a continuous injury. As we explained there, such

provisions have historically been understood as referring only to

“other insurance” that was issued for the same policy period, not

(as the excess insurers suggest) other insurance issued “for

different policy periods.” (Montrose III, supra, 9 Cal.5th at

p. 230; see id. at p. 234.) Indeed, as Montrose III noted and we

reiterate here, most jurisdictions that have addressed analogous

arguments have concluded that “ ‘other insurance’ clauses” do

not mandate horizontal exhaustion nor are they otherwise

relevant to policies issued during different periods of coverage.

(Id. at pp. 232–233.) The Restatement of Liability Insurance

likewise explains that “ ‘ “other insurance” ’ clauses have

generally been used to address ‘[a]llocation questions with

respect to overlapping concurrent policies.’ ” (Montrose III, at

p. 232, quoting Rest., Liability Insurance, § 40, com. c, p. 345.)

The excess insurers have presented no argument as to why the

historical understanding of “other insurance” clauses, which is

generally supportive of vertical rather than horizontal

exhaustion, is inapplicable when the excess policy sits over a

primary policy.

The first-level excess policies also share the same general

characteristics that we found in Montrose III to be “strongly

suggest[ive]” of requiring only vertical, not horizontal

exhaustion. (Montrose III, supra, 9 Cal.5th at p. 233.) For

example, the excess policies “include or reference schedules of

underlying insurance — all for the same policy period.” (Id. at

p. 234.) Indeed, every single policy at issue in this case describes

33

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

its attachment point by directly referencing primary insurance

that was issued for the same policy period. As in Montrose III,

we believe these schedules are most reasonably construed as 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.” (Ibid.)10

Moreover, several of the policies not only refer to

underlying primary insurance issued during the same policy

period, but also “referenc[e] a specific dollar amount of

underlying insurance in the same policy period that must be

exhausted.” (Montrose III, supra, 9 Cal.5th at p. 233.) Under

the excess insurers’ theory of horizontal exhaustion, however,

this attachment would not occur until Kaiser had exhausted

that amount, plus the limits of every other primary policy it had

obtained for every relevant policy period.

Furthermore, the same practical concerns with

administering a rule of horizontal exhaustion that we discussed

in Montrose III are likewise implicated here. We explained, for

example, that applying horizontal exhaustion would be “far from

straightforward” given that the attachment points of the

insured’s layers of excess insurance did not align from policy

year to policy year. (Montrose III, supra, 9 Cal.5th at p. 234.)

10

The first-level excess policies also include provisions

stating that upon exhaustion of those scheduled underlying

policies, the excess policy shall “continue in force as underlying

insurance.” Again, these express references to the directly

underlying primary policies tend to support a view of vertical,

rather than horizontal exhaustion.

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AND GYPSUM CORP.

Opinion of the Court by Groban, J.

The Court of Appeal concluded this rationale was inapplicable

in the current context because “there is only one underlying

layer of insurance, namely, primary insurance and it is easy to

ascertain whether that insurance has been exhausted.” That

reasoning, however, overlooks that the plain text of the first-

level excess policies’ “other insurance” provisions is not limited

to other underlying primary insurance. Rather, the provisions

speak generally to “any other insurance” or “any other

underlying insurance.” (Italics added.) If the excess insurers

are correct that these provisions were intended to apply to

insurance purchased for different policy periods, their plain

language indicates that Kaiser would have to exhaust any other

underlying insurance — i.e., any policy with a lower attachment

point — not merely any other underlying primary insurance.

While that might not create any particular administrative

complications if the attachment points of Kaiser’s first-level

excess policies were standardized across policy years, the record

shows that is not the case. Rather, as in Montrose III, the first-

level excess policies appear to come in different “shapes and

sizes.” (Montrose III, supra, 9 Cal.5th at p. 234.) For example,

in the 1983 policy year, Kaiser obtained primary insurance for

the first $2 million of liability and obtained a first-level excess

policy that attaches above that amount. In 1958, however,

Kaiser obtained only $1 million in primary insurance with a

first-level excess policy for the next $2 million. If the “other

insurance” provisions truly apply across all policy periods, does

Kaiser’s 1983 first-level excess policy (with an attachment point

of $2 million) require Kaiser to exhaust the 1958 primary policy

(with an attachment point of $1 million) and the first $1 million

of the 1958 first-level excess policy? Or can Kaiser access the

35

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

1983 first-level excess policy as soon as the $1 million 1958

primary policy is exhausted? Stated more simply, if the $1

million 1958 primary policy qualifies as “other underlying

insurance” to the 1983 first-level excess policy, why wouldn’t the

initial $1 million of the 1958 first-level excess policy likewise

qualify as underlying insurance that would have to be

exhausted prior to accessing the 1983 policy? As noted in

Montrose III, “[t]he policies’ silence on these basic, foundational

questions tends to undermine the idea the parties expected . . .

a rule [of horizontal exhaustion] to apply.” (Id. at p. 235.)

Finally, Montrose III expressed concern that “because the

exclusions, terms, and conditions may vary from one [excess]

policy to another” (Montrose III, supra, 9 Cal.5th at p. 235), a

rule of horizontal exhaustion 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” (ibid.).

Again, neither the Court of Appeal nor the excess insurers have

provided any explanation as to why those concerns are

inapplicable in the context of primary insurance. During the

relevant time frame Kaiser bought dozens of primary policies

from multiple insurers. While the parties have not provided

detailed information regarding the specific terms of those

policies, the excess insurers’ own briefing indicates that the

terms of the primary policies vary with respect to coverage

amounts, aggregate limits, allocation of defense costs and

deductible requirements. Moreover, as discussed above, Kaiser,

Truck and the excess insurers previously spent years litigating

whether a specific provision in Truck’s 1974 policy barred Kaiser

from accessing any of Truck’s other 18 primary policies (a

36

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

provision apparently absent in the non-Truck primary policies).

Thus, based on the limited record before us, it is reasonable to

assume that the same concerns regarding the amount of

litigation a rule of horizontal exhaustion would create due to

variations in policy terms and conditions are equally present in

the context of primary insurance.11

Despite the textual overlap between the policy language

at issue here and in Montrose III, and the similar practical

complications that a rule of horizontal exhaustion would present

to the insured in the context of primary insurance, the Court of

Appeal concluded that “other insurance” provisions should

nonetheless be assigned a different meaning when the excess

policy sits over primary insurance. The sole reason the court

provided in support of this conclusion was the “qualitative[]”

distinctions between primary and excess insurance. As

explained by the court, primary policies receive higher

premiums because they “attach as first-dollar coverage and have

an immediate obligation to respond,” whereas excess policies

may never be called upon to indemnify. Moreover, primary

insurers generally have the right to control defense and

settlement without input from excess insurers and “do not use

11

Although Kaiser has joined the excess insurers in arguing

that Truck’s contribution claim should be denied on unfairness

grounds, it has notably declined to take a position as to whether

the Court of Appeal properly interpreted the first-level excess

policies as requiring horizontal exhaustion. In the prior Kaiser

Cement appeal, however, Kaiser specifically argued against

such a rule, contending that it was “objectively reasonable” to

expect that its 1974 first-level excess policy would become

available immediately upon exhaustion of the underlying 1974

Truck primary policy.

37

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

defense costs to reduce limits.” The court provided no further

discussion or explanation as to why it believed these distinctions

warranted a departure from the interpretation of “other

insurance” provisions that we adopted in Montrose III. We find

the Court of Appeal’s reasoning unavailing.

In SantaFe, supra, 52 Cal.App.5th 19, the First District

reached a contrary conclusion, reasoning that the distinctions

between primary insurance and excess insurance “provide little

justification for construing the policy language interpreted in

Montrose III differently.” (Id. at p. 28.) Regarding the

differences in the premiums paid for primary and excess

insurance, the court explained that “the evaluation of risk based

on the assumption of vertical exhaustion is straightforward and

can be made based on known parameters. However, if the risk

assessment were to be made based on the assumption of

horizontal exhaustion, the evaluation would be speculative and

unpredictable” as the “level of liability at which the excess

coverage would attach would be unascertainable. . . . The

difference between premiums paid for excess and for primary

policies does not justify an interpretation that renders the point

of attachment so unpredictable and unascertainable when the

policy is issued.” (Id. at p. 29.)

Regarding “the differing defense obligations” between

primary and excess insurance (SantaFe, supra, 52 Cal.App.5th

at p. 29), the court explained that requiring the insured to

exhaust only the directly underlying primary policy does not

alter the “well settled [rule] that an excess insurer [generally]

has no duty to defend unless the underlying primary insurance

is exhausted” (ibid.). The court noted that “[f]rom the

perspective of the insured, one would reasonably expect the

38

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

excess insurer to contribute to the defense once the scheduled

primary policies have been exhausted and the attachment

points reached.” (Ibid.)12

We believe that SantaFe has the better view. We are not

persuaded that the differences in characteristics between

primary and excess insurance is sufficient to demonstrate that

“other insurance” provisions are meant to require horizontal

exhaustion when used in first-level excess policies. As noted,

Montrose III concluded that identical language appearing in

higher-level excess policies is most reasonably construed as

applying only to underlying insurance that covers the same

policy period. We do not believe that the meaning of the

language is transformed to say exactly what we concluded it did

not say in Montrose III merely because the policy sits over

primary insurance rather than another level of excess

insurance.

Furthermore, as SantaFe explained, even under the rule

of vertical exhaustion that we adopted in Montrose III, the

differences in premiums between primary and excess insurance

continue to reflect the fact that the excess insurer still has no

indemnity obligations unless and until the insured exhausts the

limits of the directly underlying primary policy. Given that

these excess policies were written long before we adopted the

all-sums-with-stacking approach to continuous injuries (see

ante, at pp. 7–9), we are dubious that the excess insurers priced

12

The specific defense obligations that a first-level excess

insurer owes to the insured, and whether defense costs are

included in the aggregate limits of the excess policy, will of

course turn on the specific terms of each excess policy.

39

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

their premiums on the assumption that their policies would not

attach until the insured had exhausted the directly underlying

primary policies along with any other primary insurance the

insured might acquire in later years. Were that truly the

insurers’ intent, we would expect a clearer statement than a

mere reference to “other insurance.” (See Montrose I, supra,

10 Cal.4th at p. 647 [“ ‘Because the insurer writes the policy, it

is held “responsible” for ambiguous policy language, which is

therefore construed in favor of coverage’ ”].) While the excess

insurers may not have anticipated the coverage and allocation

rules that have emerged from the Montrose, Aerojet, and

Continental line of decisions, we cannot now rewrite what they

promised to the insured.

We are also dubious that even after our adoption of the all-

sums-with-stacking approach, excess insurers would choose to

price premiums — or that the insured would agree to pay

premiums — based on a horizontal exhaustion approach that

carries the inherent uncertainty of what other primary

insurance the insured might acquire in later years. By raising

the excess policy’s attachment point with each subsequent

primary policy that the insured acquires during the period of

continuous injury, a rule of horizontal exhaustion effectively

operates to penalize the insured for obtaining more insurance.

It is not clear why the insured would agree to such an approach.

Thus, absent clear policy language to that effect, we decline to

read “other insurance” language to reflect such an agreement

between the insured and excess insurer.

In sum, we believe that the language of the first-level

excess policies, when considered in conjunction with the

insured’s reasonable expectations and the historical role of

40

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

“other insurance” provisions, is most naturally read to mean

that the insured may access the policies upon exhaustion of the

directly underlying policies that were purchased for the same

period. Excess insurers do, however, remain free to write their

future excess policies in a manner that expressly requires

horizontal exhaustion. (See Montrose III, supra, 9 Cal.5th at

p. 237 [“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”].)

As noted above, Community Redevelopment, supra,

50 Cal.App.4th 329, which predates our decision in Montrose III,

reached a different conclusion. The court there found that

similarly worded “other insurance” provisions required the

insured to horizontally exhaust all primary insurance. As noted

above, in reaching that conclusion, the court relied primarily on

case law that addressed noncontinuous injury claims (i.e.,

claims that triggered only one policy period). (See ante, at

pp. 20–22; Community Redevelopment, at p. 339, citing Olympic

Ins. Co. v. Employers Surplus Lines Ins. Co. (1981)

126 Cal.App.3d 593 [concerning an aircraft collision],

McConnell v. Underwriters at Lloyds (1961) 56 Cal.2d 637

[concerning an automobile collision], and Lamb v. Belt Cas. Co.

(1935) 3 Cal.App.2d 624 [concerning an automobile collision].)

The courts in those cases held that the excess policies’ “other

insurance” provisions required the insured to exhaust not only

the underlying primary insurance expressly listed in the excess

policy, but also any other underlying primary insurance that the

insured had obtained for the same policy period. (See ante, at

p. 21.) Community Redevelopment concluded that “other

41

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

insurance” provisions should operate in the same manner for

continuous injury claims that trigger multiple policy periods.

Community Redevelopment, however, failed to recognize

that cases construing “other insurance” provisions in the context

of noncontinuous injuries do not speak to the ambiguity that we

address here (which was the same ambiguity at issue in

Montrose III): are “other insurance” clauses most reasonably

construed as applying to other underlying insurance issued

during the same policy year or do such clauses extend to other

underlying insurance issued during different policy years within

the continuous period of injury? Because cases addressing

noncontinuous injury claims do not speak to this ambiguity,

Community Redevelopment erred in relying on them.13

For the reasons explained above, we disapprove

Community Redevelopment’s conclusion that standardized

“other insurance” provisions appearing in first-level excess

policies compel a rule of horizontal exhaustion. We likewise

disapprove language in Padilla Construction Co., Inc. v.

Transportation Ins. Co. (2007) 150 Cal.App.4th 984 and

13

In addition to finding that the “other insurance” provisions

compelled a rule of horizontal exhaustion, the Community

Redevelopment court believed that “a horizontal exhaustion rule

. . . is most consistent with the [all-sums] principles enunciated

in Montrose [I, supra, 10 Cal.4th 645].” (Community

Redevelopment, supra, 50 Cal.App.4th at p. 340.) However, we

rejected an essentially identical argument in Montrose III. (See

Montrose III, supra, 9 Cal.5th at pp. 235–236 [rejecting

insurers’ assertion that a “rule of horizontal exhaustion is

logically compelled by our adoption of an all-sums-with-stacking

approach to liability for long-tail injuries”; “There is no evident

inconsistency between an all sums approach and [vertical

exhaustion]”].)

42

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

Stonewall Ins. Co. v. City of Palos Verdes Estates (1996)

46 Cal.App.4th 1810, suggesting that California law generally

requires horizontal exhaustion of all primary insurance in cases

of continuous loss. (See Padilla, at pp. 986–987; Stonewall, at

pp. 1852–1853.)

2. Additional considerations regarding Truck’s

contribution claim

Montrose III was a coverage action that required us to

determine whether the insured was permitted to access its

higher-level excess policies. The answer to that question

depended entirely on our interpretation of the policies at issue

in that case. Here, however, we are faced with an equitable

contribution claim between insurers. As noted above, the terms

of the insurers’ policies comprise only one of the factors courts

may consider when evaluating whether contribution would

“ ‘accomplish ultimate justice’ ” (Signal, supra, 27 Cal.3d at

p. 369) in a particular case (see ibid.; ante, at pp. 17–18). Thus,

the fact that we have rejected the Court of Appeal’s conclusion

that the excess policies do not create any indemnity obligation

until all primary insurance has been exhausted, and instead

have interpreted those policies in a manner that would permit

the insured (Kaiser) to access the policies upon exhaustion of the

directly underlying primary policies, does not resolve whether

Truck is entitled to contribution from the excess insurers.

To that end, the excess insurers and Kaiser argue that

even if, as a matter of contract interpretation, the policies are

most reasonably construed as allowing the insured (Kaiser) to

access the first-level excess policies upon exhaustion of the

directly underlying primary insurance, it would nonetheless

remain unfair as a matter of equity to ever order an excess

43

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

insurer to contribute to a primary insurer given the distinct role

those two types of carriers play in covering a loss. Although we

have concluded that the qualitative distinctions between

primary and excess insurance do not present a sufficient basis

to depart from the interpretation of the “other insurance”

provisions that we adopted in Montrose III (i.e., that such

provisions impose only a rule of vertical exhaustion on the

insured), whether those distinctions might have more salience

in the context of equitable contribution between insurers

remains an open question. (See generally Dart, supra, 28

Cal.4th at p. 1080 [“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”];

SantaFe, supra, 52 Cal.App.5th at p. 29 [whether a policy

requires horizontal or vertical exhaustion presents “a different

question” than determining “the rights of . . . carriers . . . to

contribution”].)

The excess insurers and Kaiser further argue that even if

there might be some circumstances where it would be

appropriate to order contribution between primary and excess

insurers, such an order would be unjust under the facts

presented in this case. They explain that because Truck agreed

to indemnify Kaiser up to $500,000 for each asbestos-related

bodily injury claim but placed no aggregate limit on coverage

(something no other primary insurer did), ordering the excess

insurers to contribute to that initial $500,000 in coverage would

effectively allow Truck to pay less coverage than it promised

under its 1974 policy. They further contend that ordering

contribution would simultaneously leave Kaiser (and asbestos

claimants) with less overall coverage by prematurely exhausting

44

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

excess insurance that could otherwise be used to cover

individual asbestos claims that exceed Truck’s $500,000 per

occurrence limit or claims that do not trigger Truck’s 1974 policy

(i.e., claims in which initial exposure occurred after the 1974

policy period). In support of these arguments, Kaiser and the

excess insurers cite expert testimony and other evidence

regarding claims allocation that was presented during the bench

trial.

Because the Court of Appeal denied contribution based

solely on its erroneous interpretation of the first-level excess

policies, it did not consider these or any other alternative

arguments related to the question of contribution. Having now

clarified that the first-level excess insurers’ indemnity

obligations to Kaiser attach upon exhaustion of the directly

underlying primary policies, we find it appropriate to remand

the matter for the court to reevaluate whether contribution

would “ ‘accomplish ultimate justice’ ” (Signal, supra, 27 Cal.3d

at p. 369) among the insurers and their policy holder. (See, e.g.,

Coast Community College Dist. v. Commission on State

Mandates (2022) 13 Cal.5th 800, 822 [remanding to allow the

court to “ ‘resolve [unexamined issues] . . . in the first

instance’ ”]; Hamilton, supra, 22 Cal.4th at p. 1149 [“It is

appropriate to remand for the Court of Appeal to resolve . . . in

the first instance” issues that the court chose “not [to] reach

because of its holdings”].)

On remand, the parties are free to raise any arguments

they believe may aid the court in deciding whether contribution

is ever appropriate between primary and excess insurers and, if

so, whether contribution would be appropriate under the

circumstances of this case. The Court of Appeal, in turn, retains

45

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

discretion to make a further remand to the trial court if it

concludes that the trial court is better positioned to address any

questions of contribution that may arise in the further

proceedings.14

III. DISPOSITION

The Court of Appeal’s judgment is reversed, and the

matter is remanded for further proceedings consistent with this

opinion.

14

Like the Court of Appeal, the trial court’s decision to deny

contribution was predicated exclusively on its finding that the

excess policies required horizontal exhaustion. (See ante, at

pp. 14–15.) As a result, the trial court did not address any of the

parties’ other arguments regarding contribution, much of which

was presented through expert testimony at trial. Thus, to the

extent the Court of Appeal concludes that Truck is potentially

eligible for contribution, it may further conclude that the trial

court is in a better position to weigh the equities at stake given

its familiarity with the parties and their relative positions in

this long-running litigation. (See Hartford Casualty Ins. Co. v.

Travelers Indemnity Co. (2003) 110 Cal.App.4th 710, 724 [“In

evaluating competing claims for equitable contribution, the trial

court exercises its discretion to weigh the equities to

‘ “ ‘accomplish ultimate justice’ ” ’ ”]; Axis, supra,

204 Cal.App.4th at p. 1228 [“in an equitable contribution action,

a court reviews the applicable facts and policies and decides

what is fair between the potential coinsurers”].) We leave those

determinations to the Court of Appeal.

46

TRUCK INSURANCE EXCHANGE v. KAISER CEMENT

AND GYPSUM CORP.

Opinion of the Court by Groban, J.

GROBAN, J.

We Concur:

GUERRERO, C. J.

CORRIGAN, J.

LIU, J.

KRUGER, J.

JENKINS, J.

EVANS, J.

47

See next page for addresses and telephone numbers for counsel who

argued in Supreme Court.

Name of Opinion Truck Insurance Exchange v. Kaiser Cement and

Gypsum Corp.

__________________________________________________________

Procedural Posture (see XX below)

Original Appeal

Original Proceeding

Review Granted (published)

Review Granted (unpublished) XX NP opn. filed 1/7/22 – 2d Dist.,

Div. 4

Rehearing Granted

__________________________________________________________

Opinion No. S273179

Date Filed: June 17, 2024

__________________________________________________________

Court: Superior

County: Los Angeles

Judge: Kenneth R. Freeman

__________________________________________________________

Counsel:

Pia Anderson Moss Hoyt, Scott R. Hoyt, Adam L. Hoyt; Greines,

Martin, Stein & Richland, Robert A. Olson, Jonathan H. Eisenman and

Edward L. Xanders for Plaintiff and Appellant.

The Cook Law Firm, Philip E. Cook and Brian J. Wright for

Defendant, Cross-complainant and Appellant Kaiser Cement and

Gypsum Corporation.

Covington & Burling, David B. Goodwin, Breanna K. Jones and Billie

T.H. Mandelbaum for United Policyholders as Amicus Curiae on behalf

of Defendant, Cross-complainant and Appellant Kaiser Cement and

Gypsum Corporation.

Morgan, Lewis & Bockius and Jeffrey S. Raskin for Santa Fe Braun,

Inc., as Amicus Curiae on behalf of Defendant, Cross-complainant and

Appellant.

Duane Morris, Brian A. Kelly, Paul J. Killion and Kathryn T.K.

Schultz for Defendant and Appellant.

Lynberg & Watkins, Sinnott, Puebla, Campagne & Curet and Wendy

E. Schultz for Cross-defendant and Appellant and Defendant and

Respondent.

Squire Patton Boggs, G. David Godwin and Tania L. Rice for

Defendant and Respondent The Continental Insurance Company.

Selman Breitman, Elizabeth M. Brockman and Calvin S. Whang for

Defendants and Respondents National Casualty Company and Sentry

Insurance a Mutual Company.

Crowell & Moring, Mark D. Plevin and Christine E. Cwiertny for

Defendants and Respondents Fireman’s Fund Insurance Company and

Allianz Underwriters Insurance Company.

Kendall Brill & Kelly, Alan Jay Weil; Shipman & Goodwin, Ruggeri

Parks Weinberg, James P. Ruggeri, Katherine M. Hance and Edward

B. Parks II for Defendant and Respondent First State Insurance

Company.

Aiwasian & Associates and Deborah A. Aiwasian for Defendant and

Respondent Westchester Fire Insurance Company.

Davis Wright Tremaine, Everett W. Jack, Jr., and Lawrence B. Burke

for Defendant and Respondent Transport Insurance Company.

Traub Lieberman Straus & Shrewsberry, Robert Dennison, Kevin P.

McNamara, Giuseppe Castaldi and Laura Siegel-Puhala for Defendant

and Respondent Evanston Insurance Company.

Counsel who argued in Supreme Court (not intended for

publication with opinion):

Robert A. Olson

Greines, Martin, Stein & Richland LLP

6420 Wilshire Boulevard, Suite 1100

Los Angeles, CA 90048

(310) 859-7811

Brian A. Kelly

Duane Morris LLP

Spear Tower, One Market Plaza, Suite 2200

San Francisco, CA 94105-1127

(415) 957-3213

Philip E. Cook

The Cook Law Firm, P.C.

601 S. Figueroa Boulevard, Suite 2050

Los Angeles, CA 90017

(213) 988-6100