        IN THE SUPREME COURT OF
               CALIFORNIA

                  DIANA NIEVES NOEL,
                  Plaintiff and Appellant,
                              v.
                 THRIFTY PAYLESS, INC.,
                 Defendant and Respondent.

                           S246490

            First Appellate District, Division Four
                           A143026

                Marin County Superior Court
                       CIV1304712



                        July 29, 2019

Chief Justice Cantil-Sakauye authored the opinion of the
Court, in which Justices Chin, Corrigan, Liu, Cuéllar, Kruger,
and Groban concurred.
              NOEL v. THRIFTY PAYLESS, INC.
                            S246490


         Opinion of the Court by Cantil-Sakauye, C. J.


       This case is a putative class action brought on behalf of
retail purchasers of an inflatable outdoor pool sold in packaging
that allegedly misled buyers about the pool’s size. We must
decide whether the trial court abused its discretion when it
denied the representative plaintiff’s motion for class
certification on the basis that he had not supplied evidence
showing how class members might be individually identified
when the time came to do so. The Court of Appeal upheld this
ruling. It reasoned that this evidence was necessary to ensure
that proper notice would be given to the class, and that without
it, the trial court could appropriately conclude that plaintiff had
not satisfied the ascertainability requirement for class
certification.
      We conclude that the trial court erred in demanding that
plaintiff offer such evidence to satisfy the ascertainability
requirement. Plaintiff’s proposed class definition articulates an
ascertainable class, in that it defines the class “in terms of
objective characteristics and common transactional facts” that
make “the ultimate identification of class members possible
when that identification becomes necessary.”           (Hicks v.
Kaufman & Broad Home Corp. (2001) 89 Cal.App.4th 908, 915
(Hicks).) As we will explain, the ascertainability requirement
does not incorporate the additional evidentiary burden that the
courts below would have imposed. We therefore reverse the



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                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


judgment of the Court of Appeal and remand the matter for
further proceedings consistent with our opinion.
                         I. BACKGROUND
      In November 2013, plaintiff James Noel1 filed a verified
complaint in Marin County Superior Court, alleging claims
under the unfair competition law (Bus. & Prof. Code, § 17200 et
seq.) (UCL), the false advertising law (Bus. & Prof. Code,
§ 17500 et seq.) (FAL), and the Consumers Legal Remedies Act
(Civ. Code, § 1750 et seq.) (CLRA).
        These claims arose out of Noel’s purchase of an inflatable
outdoor pool marketed as Kids Stuff Ready Set Pool 8FT X 25IN
(hereinafter Ready Set Pool) from a Rite Aid drugstore in San
Rafael.2 Noel alleges that his purchase of the pool was
influenced by a photograph that appears on its packaging. This
photo, as it appears within the complaint, indicates that the pool
can handily accommodate several adults when inflated and
filled:




1
      James Noel died while this action was pending before the
Court of Appeal and has been replaced as plaintiff by his widow,
Diana Nieves Noel. To avoid confusion, our opinion refers to
both as “Noel,” and uses the masculine pronoun whenever
referring to plaintiff.
2
      Defendant Thrifty Payless, Inc., operates the Rite Aid
drugstore chain. Our opinion refers to defendant as “Rite Aid.”


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                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.




Noel asserts that when he set up the pool, he discovered that it
was much smaller than the photograph on the box conveys. To
demonstrate this, the complaint also includes another
photograph of the pool, as inflated and filled:




Noel’s claims under the UCL, the FAL, and the CLRA are
premised on this alleged discrepancy.3
     In May 2014, Noel moved to certify a class defined as “[a]ll
persons who purchased the Ready Set Pool at a Rite Aid store

3
      Rite Aid responds that Noel did not set up the pool
correctly.


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                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


located in California within the four years preceding the date of
the filing of this action.” By that time, Noel had conducted
discovery that yielded the total number of Ready Set Pools that
Rite Aid had sold in California during the class period (20,752,
with 2,479 of the pools being returned), and the revenue
obtained through these sales ($949,279.34). Noel’s discovery did
not, however, delve into whether Rite Aid kept records of these
transactions, or into the more general subjects of whether and
how Rite Aid collected contact information from its customers
and how it disseminated information to them.4
       In opposing class certification, Rite Aid argued that Noel
had not demonstrated the existence of an ascertainable class —
a well-established prerequisite for class certification under
section 382 of the Code of Civil Procedure. (See, e.g., Brinker
Restaurant Corp. v. Superior Court (2012) 53 Cal.4th 1004, 1021
(Brinker); In re Tobacco II Cases (2009) 46 Cal.4th 298, 318 (In
re Tobacco II); Sav-On Drug Stores, Inc. v. Superior Court (2004)
34 Cal.4th 319, 326 (Sav-On); Linder v. Thrifty Oil Co. (2000) 23
Cal.4th 429, 435 (Linder); Richmond v. Dart Industries, Inc.
(1981) 29 Cal.3d 462, 470 (Richmond); Vasquez v. Superior
Court (1971) 4 Cal.3d 800, 809 (Vasquez); Daar v. Yellow Cab
Co. (1967) 67 Cal.2d 695, 704 (Daar).) Specifically, Rite Aid
asserted that to show an ascertainable class, Noel bore the
burden of introducing evidence in connection with his
certification motion that would show how members of the
putative class could be identified later in the proceeding, so they

4
      In his deposition, Noel testified that he had not retained
the store receipt associated with his purchase of a Ready Set
Pool, but had bought the pool using a debit card and possessed
bank records containing an entry consistent with such a
transaction.


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                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


could be provided with notice of the pending action. In Rite Aid’s
view, Noel’s failure to supply such proof doomed his certification
effort.
      Noel responded that he had no obligation to offer evidence
on this issue in order to secure certification of the class he
proposed. His briefing in support of class certification described
various ways in which notice of the action might be distributed
to absent class members when the time came to do so.5 He
explained that “modern day point of sale systems used by major
retailers such as Rite Aid can already track purchases by
customers who pay by credit card. Many of those customers
likely belong to Rite Aid’s reward savings program, which
means Rite Aid has contact information for these individuals.
Thus, Rite Aid should be quite capable of sending individual
notices to these purchasers.” Noel also claimed that Rite Aid
“sends weekly e-mails to subscribers alerting them to new sales
and deals” and mails out weekly advertisements to California
customers, providing two other avenues through which notice
could be provided to absent class members. However, Noel
pointed to no evidence in the record (whether in the form of
declarations, interrogatory responses or admissions by Rite Aid,
deposition testimony, or information presented via a request for
judicial notice) that substantiated his assertions regarding how
class members could be notified. He did not, for example, supply
the trial court with specific proof that, through a loyalty




5
       Noel advanced certain methods of identifying class
members to explain why, in his view, published notice (although
possible) might be unnecessary. (See Civ. Code, § 1781, subd.
(c)(2).)


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                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


program, Rite Aid has access to pertinent customer contact
information.
       The trial court denied the motion for class certification.
The court’s order explained that “[w]hile the court might
reasonably infer that the class, as defined by [p]laintiff, could be
ascertained based on common business practices and record
keeping, [p]laintiff has presented no evidence on this subject.
Absent some evidence as to what method or methods will be
utilized to identify the class members, what records are
available, (either from [d]efendant, the manufacturer, or other
entities such as banks or credit institutions), how those records
would be obtained, what those records will show, and how
burdensome their production would be, the court is without
sufficient evidence to determine whether the proposed class is
ascertainable. Accordingly, [the] motion to certify must be
denied.”
      The trial court also declined to certify a class in connection
with Noel’s CLRA claim for a second, separate reason. In the
court’s view, common issues did not predominate with this claim
because reliance had to be proved individually as to each class
member. Finally, the court also found “that a class action is not
superior to numerous individual actions, in light of the above
findings. The class action will be no more efficient than
individual actions in light of the individual issues that must be
presented on the issue of reliance and damages.” The court’s
order was not clear whether this last determination applied only
to the CLRA class, as might be inferred by the reference to
reliance, or to the action as a whole.
      After Noel appealed (see Linder, supra, 23 Cal.4th at
p. 435 [denial of certification to an entire class is an appealable


                                   6
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


order]), the Court of Appeal found no abuse of discretion in the
denial of class certification. (Noel v. Thrifty Payless, Inc. (2017)
17 Cal.App.5th 1315, 1321 (Noel).) Addressing the superior
court’s determination that Noel had not shown an ascertainable
class, the reviewing court diagnosed “the underlying problem
with the class certification motion” as “class counsel’s premature
filing of the motion without first conducting sufficient discovery
to meet its burden of demonstrating there are means of
identifying members of the putative class so that they might be
notified of the pendency of the litigation.” (Ibid.) The Court of
Appeal emphasized that Noel had “submitted nothing offering a
glimmer of insight into who purchased the pools or how one
might find that out. He neither described nor produced Rite
Aid’s records . . . nor did he indicate how much . . . information
those records might reveal. Unless Noel could propose some
realistic way of associating names and contact information with
the 20,000-plus transactions identified by interrogatory
response, there remained a serious due process question in
certifying a class action.” (Id., at p. 1328.) The Court of Appeal
continued, “While Noel was not required to actually identify the
20,000-plus individuals who bought pools, his failure to come up
with any means of identifying them was a legitimate basis for
denying class certification.” (Ibid.)6




6
      The Court of Appeal stressed that “the modest evidentiary
burden” (Noel, supra, 17 Cal.App.5th at p. 1333) it would impose
upon plaintiffs seeking class certification was “something that,
with proper foresight in the early stages of a class proceeding,
can be addressed quite easily, especially if it is given the same
level of care and attention as, for example, drafting a precise
description of the class” (id., at pp. 1333-1334).


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                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


        The Court of Appeal sought to harmonize its
understanding of the ascertainability requirement with the
views of other courts. The Court of Appeal noted that the court
in Estrada v. FedEx Ground Package System, Inc. (2007) 154
Cal.App.4th 1 (Estrada) had regarded a class as “ ‘ascertainable
if it identifies a group of unnamed plaintiffs by describing a set
of common characteristics sufficient to allow a member of that
group to identify himself as having a right to recover based on
the description.’ ” (Noel, supra, 17 Cal.App.5th at p. 1326,
quoting Estrada, at p. 14, italics omitted.) The Court of Appeal
also observed that Sotelo v. MediaNews Group, Inc. (2012) 207
Cal.App.4th 639 (Sotelo) had prescribed a “more demanding
standard” for ascertainability (Noel, at p. 1327), having
explained, “ ‘The ascertainability requirement is a due process
safeguard, ensuring that notice can be provided “to putative
class members as to whom the judgment in the action will be res
judicata.” [Citation.] “Class members are ‘ascertainable’ where
they may be readily identified without unreasonable expense or
time by reference to official records. [Citation.]” [Citation.] In
determining whether a class is ascertainable, the trial court
examines the class definition, the size of the class and the means
of identifying class members.’ ” (Noel, at p. 1327, italics omitted,
quoting Sotelo, at pp. 647-648.) Addressing these different
formulations, the Court of Appeal in this case endorsed the
Sotelo approach — describing it as “a more pragmatic approach
in determining ascertainability, and one which comports with
the rationale underlying the ascertainability requirement”
(Noel, at p. 1327) — but also sought to reconcile these views by
characterizing “Sotelo’s three-factor test as a refinement of the
ascertainability prong of the Estrada test when that prong . . .
requires a closer look.” (Noel, at p. 1329.)


                                   8
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


       Although the appellate court below sought to reconcile the
views of the Courts of Appeal, it recognized that some tension
might exist between its analysis and that in Aguirre v. Amscan
Holdings, Inc. (2015) 234 Cal.App.4th 1290 (Aguirre). The
Court of Appeal in Aguirre held that a superior court had erred
when it declined to certify a putative consumer class on
ascertainability grounds. (Id., at p. 1299.) The Aguirre court
explained that a “representative plaintiff need not identify,
much less locate, individual class members to establish the
existence of an ascertainable class. [Citations.] Nor must the
representative plaintiff establish a means for providing personal
notice of the action to individual class members.” (Id., at p. 1301,
italics added.) The Court of Appeal in this case sought to bridge
the distance between its views and those expressed by the
Aguirre court by noting that the class in Aguirre could have
included up to a million members, whereas there were only
approximately 20,000 purchasers of the Ready Set Pool. With
the larger class, the Court of Appeal surmised, “perhaps
assuming personal notice cannot be given was realistic, but with
a class size of 20,000 we are not so quick to make that
assumption.” (Noel, supra, 17 Cal.App.5th at p. 1331.) The
Court of Appeal nevertheless conceded that its view of the
ascertainability requirement “may be contrary to that of
Aguirre.” (Id., at p. 1333.)
      The Court of Appeal also found no abuse of discretion in
the superior court’s refusal to certify a CLRA class on the basis
that common issues did not predominate. (Noel, supra, 17
Cal.App.5th at pp. 1334-1336.) This aspect of the trial court’s
order is not presently before us. Turning to the lower court’s
determination that a class action was not a superior vehicle for
pressing the claims at issue, the Court of Appeal noted the


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                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


ambiguous scope of this ruling. (Id., at p. 1336.) The court also
recognized Court of Appeal precedent holding that superiority is
not required for a class action brought under the CLRA. (Noel,
at p. 1336, citing Thompson v. Automobile Club of Southern
California (2013) 217 Cal.App.4th 719, 727-728; see also Hogya
v. Superior Court (1977) 75 Cal.App.3d 122, 132-136.)
Nevertheless, the court found any error harmless: “If the court
intended to include lack of superiority as a reason for rejecting
class certification on the CLRA cause of action, that was error,
but harmless due to the other valid reasons for denying class
certification. If the court intended its negative superiority
finding to apply only to the FAL and UCL causes of action, then
it was supported by the evidence and did not amount to an abuse
of discretion.” (Noel, at p. 1336.)
      We granted review to clarify what the ascertainability
requirement for class certification involves.
                         II. DISCUSSION
      In determining whether the trial court abused its
discretion, we begin by surveying the relevant general principles
applicable to class certification. We then turn to case law that
has considered what it means for a class to be ascertainable.
Drawing from this review, we conclude that the functions
properly assigned to the ascertainability requirement are best
served by regarding a class as ascertainable when it is defined
“in terms of objective characteristics and common transactional
facts” that make “the ultimate identification of class members
possible when that identification becomes necessary.” (Hicks,
supra, 89 Cal.App.4th at p. 915.) This standard was satisfied
here because the class definition provided a basis for class
members to self-identify. The courts below erred in importing


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                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


an additional evidentiary burden into the ascertainability
requirement.
      A. General Principles
       In reviewing a class certification order, our inquiry is
“narrowly circumscribed.” (Brinker, supra, 53 Cal.4th at
p. 1022.) “ ‘The decision to certify a class rests squarely within
the discretion of the trial court, and we afford that decision great
deference on appeal, reversing only for a manifest abuse of
discretion: “Because trial courts are ideally situated to evaluate
the efficiencies and practicalities of permitting group action,
they are afforded great discretion in granting or denying
certification.” [Citation.] A certification order generally will not
be disturbed unless (1) it is unsupported by substantial
evidence, (2) it rests on improper criteria, or (3) it rests on
erroneous legal assumptions. ’ ” (Ibid.) “Under this standard,
an order based upon improper criteria or incorrect assumptions
calls for reversal ‘ “even though there may be substantial
evidence to support the court’s order.” ’ ” (Linder, supra, 23
Cal.4th at p. 436; see also Ayala v. Antelope Valley Newspapers,
Inc. (2014) 59 Cal.4th 522, 537 [“[a] certification decision is
reviewed for abuse of discretion, but when the supporting
reasoning reveals the court based its decision on erroneous legal
assumptions about the relevant questions, that decision cannot
stand”].)
      Here, plaintiff sought certification of a class pursuant to
section 382 of the Code of Civil Procedure, which provides a
general authorization for class actions, and section 1781 of the
Civil Code, the provisions of which govern class suits brought
under the CLRA and inform class action practice more




                                   11
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


generally. (See Linder, supra, 23 Cal.4th at p. 437; Vasquez,
supra, 4 Cal.3d at p. 820.)
       Section 382 of the Code of Civil Procedure authorizes a
class action when “the question is one of a common or general
interest, of many persons, or when the parties are numerous,
and it is impracticable to bring them all before the court.” “[W]e
have articulated clear requirements for the certification of a
class” under this statute. (Brinker, supra, 53 Cal.4th at p. 1021.)
“The party advocating class treatment must demonstrate the
existence of an ascertainable and sufficiently numerous class, a
well-defined community of interest, and substantial benefits
from certification that render proceeding as a class superior to
the alternatives.”     (Ibid.)     “The community of interest
requirement involves three factors: ‘(1) predominant common
questions of law or fact; (2) class representatives with claims or
defenses typical of the class; and (3) class representatives who
can adequately represent the class.’ ” (Linder, supra, 23 Cal.4th
at p. 435.) Regarding the first of these factors, we have
recognized “ ‘[a]s a general rule’ ” that “ ‘if the defendant’s
liability can be determined by facts common to all members of
the class, a class will be certified even if the members must
individually prove their damages.’ ” (Brinker, at p. 1022; see
also Daar, supra, 67 Cal.2d at p. 706.) Relatedly, “In certifying
a class action, the court must also conclude that litigation of
individual issues, including those arising from affirmative
defenses, can be managed fairly and efficiently.” (Duran v. U.S.
Bank National Assn. (2014) 59 Cal.4th 1, 28-29.) Finally, other
considerations relevant to certification “include the probability
that each class member will come forward ultimately to prove
his or her separate claim to a portion of the total recovery and



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                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


whether the class approach would actually serve to deter and
redress alleged wrongdoing.” (Linder, at p. 435.)
       The CLRA includes its own set of requirements for class
certification. Under this statute, “The court shall permit [a
class] suit to be maintained on behalf of all members of the
represented class if all of the following conditions exist: (1) It is
impracticable to bring all members of the class before the court.
[¶] (2) The questions of law or fact common to the class are
substantially similar and predominate over the questions
affecting the individual members. [¶] (3) The claims or defenses
of the representative plaintiffs are typical of the claims or
defenses of the class. [¶] (4) The representative plaintiffs will
fairly and adequately protect the interests of the class.” (Civ.
Code, § 1781, subd. (b).) We have not specifically identified
ascertainability as an essential element for class certification
under the CLRA, as we have for class actions authorized by
section 382 of the Code of Civil Procedure. Yet the Courts of
Appeal have routinely demanded that CLRA plaintiffs
demonstrate the existence of an ascertainable class (see, e.g.,
Apple Inc. v. Superior Court (2018) 19 Cal.App.5th 1101, 1116,
fn. 2; In re Vioxx Class Cases (2009) 180 Cal.App.4th 116, 128,
fn. 12), and this requirement is fairly subsumed in the need to
have a coherent “represented class” to pursue a class action
under the statute (Civ. Code, §1781, subd. (b)).
      B. Past Discussions of Ascertainability
       Although our case law has been clear that a plaintiff must
show an ascertainable class as a prerequisite to class
certification, neither our decisions nor those of the Courts of
Appeal have been as pellucid in explaining what this
requirement entails.


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                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


         1. Weaver
      Our first discussion of class ascertainability appeared
more than 70 years ago — a time when class action litigation
remained in a formative stage. (See Miller, The Preservation
and Rejuvenation of Aggregate Litigation: A Systemic
Imperative (2014) 64 Emory L.J. 293, 294.) In this milieu, the
four plaintiffs in Weaver v. Pasadena Tournament of Roses
(1948) 32 Cal.2d 833 (Weaver) brought a lawsuit to recover
statutory penalties for an allegedly wrongful refusal to admit
them to the 1947 Rose Bowl football game. (Id., at p. 835.) The
plaintiffs sought to pursue the matter as a representative suit
on behalf of themselves and hundreds of other would-be patrons
who also had waited in line for tickets that ended up being
allocated through assertedly improper private sales. (Id., at p.
836.)
      We agreed with the superior court’s determination that
the suit was not an appropriate representative action. (Weaver,
supra, 32 Cal.2d at p. 835.) We stressed, “In the present case
there is no ascertainable class, such as the stockholders,
bondholders, or creditors of an organization. Rather, there is
only a large number of individuals, each of whom may or may
not have, or care to assert, a claim against the operators of the
1947 Rose Bowl Game for the alleged wrongful refusal of
admission thereto. Each of such claimants must establish
separately that he was refused admission, and that such refusal
was wrongful . . . . While each would be ‘similarly situated’ in
that his cause of action arises under the same statute, his
recovery would rest on a distinct premise correlative with
varying proof as to the facts of his particular case. In such
circumstances there is not the necessary ‘common or general
interest’ in the subject-matter of the litigation appropriate to the

                                   14
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


maintenance of a representative action as that type of
proceeding has been analyzed in the adjudicated cases.” (Id., at
pp. 839-840.)
      Our opinion in Weaver, supra, 32 Cal.2d 833, also noted
“one further point” that provided additional support for the trial
court’s ruling. (Id., at p. 842.) We observed, “In cases properly
falling within the category of representative litigation, the
judgment or decree would be res judicata for or against the class
sought to be represented. [Citations.] But that result could not
be extended to entirely separate causes of action, such as the
four plaintiffs have pleaded here, so as to bind ‘several hundred
individuals’ who are not named, and who are, so far as the
complaint shows, unknown and unascertainable. Rather, these
unknown parties are ascertainable only insofar as each may
come forward and individually present proof of all the facts
necessary to authorize a recovery in accordance with the merits
of his particular case, and judgment in one would by no means
be a judgment in any other. Plaintiffs here do not claim to
represent an association or protective committee nor do they
present any reasonable basis for ascertaining the members of
the alleged class for whom they seek to act in this litigation.
[Citation.] In short, plaintiffs’ complaint can be regarded as no
more than an invitation to such persons as may be interested to
join with them in this action in seeking relief ‘arising out of the
same transaction or series of transactions’ [citation], but such
situation furnishes no ground for the maintenance of a
representative proceeding. . . .” (Id., at pp. 842-843.)
         2. Chance
     We next discussed ascertainability in the context of a
representative proceeding in Chance v. Superior Court (1962)


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                  NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


58 Cal.2d 275 (Chance). The plaintiffs in Chance sued on behalf
of themselves and all other owners of promissory notes secured
by 2,139 trust deeds on specific parcels within a tract of land.
(Id., at pp. 278-279.) The plaintiffs alleged that they and other
members of the putative class had been ensnared in a scheme in
which each deed of trust was associated with only a miniscule
parcel. (Id., at p. 280.) The plaintiffs sought a collective
foreclosure, the proceeds of which would help mitigate their
investment losses. (Id., at p. 283.)
      In concluding that this suit could be brought as a
representative action, we first addressed whether the requisite
community of interest existed among class members. We
concluded that it did. (Chance, supra, 58 Cal.2d at pp. 284-286.)
Only later did we discuss ascertainability. Our analysis
provided, “[A]ll of the members of the instant class are
ascertainable (compare with Weaver v. Pasadena Tournament of
Roses Assn, supra, 32 Cal.2d 833, 839-840, 843), and it is
assumed that they will be given notice of the pending class
foreclosure action by registered mail or other like reliable
method [citation], thereby being afforded an opportunity to
decide whether to appear and argue for any and all appropriate
or available forms of redress desirable from their individual
points of view, against the named defendants.” (Id., at p. 290.)
        3. Daar
      Our most extensive discussion of class ascertainability
appeared five years after Chance, in Daar, supra, 67 Cal.2d 695.
The plaintiff in Daar sued the Yellow Cab Company for allegedly
overcharging him and other taxi customers. (Id., at pp. 699-
700.) He sought certification of both a subclass of customers who
had paid for taxi services with script book coupons, and another


                                  16
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


subclass of customers who had paid with cash. Regarding the
first of these subclasses, plaintiff alleged “that the names and
addresses of all purchasers and users of script books can be
definitely ascertained from defendant’s books and records.” (Id.,
at p. 700.) No similar assertions relevant to identification
appeared in the class allegations pertaining to cash customers,
as related in a separate count. (Id., at p. 702.)
      The defendant in Daar had successfully demurred to the
complaint. (Daar, supra, 67 Cal.2d at p. 698.) We reversed,
holding that the allegations in each count stated facts sufficient
for class treatment under section 382 of the Code of Civil
Procedure. (Daar, at pp. 714, 717.) In relating the background
legal principles that guided our analysis, we explained that “it
uniformly has been held that two requirements must be met in
order to sustain any class action: (1) there must be an
ascertainable class [citations]; and (2) there must be a well
defined community of interest in the questions of law and fact
involved affecting the parties to be represented.” (Id., at p. 704.)
In describing the first of these requirements, we cited to our
decisions in Weaver, supra, 32 Cal.2d 833, and Chance, supra,
58 Cal.2d 275, and further explained that “[a]pplicable
precedents indicate that in observing the ascertainable class
requirement they are at the same time giving recognition to the
principle that a group of individuals’ rights to recover, each of
which is based on a separate set of facts, cannot be determined
by a judgment in a class action. To put it in another way,
although a judgment in a class action is res judicata as to claims
of members of the class represented therein [citations], res
judicata will not preclude subsequent actions by those whose
rights to recover are based upon different facts. Therefore, such



                                   17
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


individuals cannot properly be brought under the umbrella of a
class action.” (Daar, at pp. 704-705.)
       As in Weaver, the description of ascertainability in Daar,
supra, 67 Cal.2d 695 did not consistently distinguish this
prerequisite for class certification from the need to establish a
community of interest among the class. Portions of our opinion
in Daar instead cast these elements as intertwined, such as our
explanation at one juncture that “whether there is an
ascertainable class depends in turn upon the community of
interest among the class members in the questions of law and
fact involved.” (Id., at p. 706.)
      Daar, supra, 67 Cal.2d 695 did clarify certain aspects of
the ascertainability inquiry, however. We explained in Daar
that the requirement that a plaintiff show an ascertainable class
does not subsume a “necessity of identifying the individual
members of such class as a prerequisite to a class suit. If the
existence of an ascertainable class has been shown, there is no
need to identify its individual members in order to bind all
members by the judgment. The fact that the class members are
unidentifiable at this point will not preclude a complete
determination of the issues affecting the class.” (Id., at p. 706.)
In the Daar matter itself, “Presumably an accounting in the suit
at bench will determine the total amount of the alleged
overcharges; any judgment will be binding on all the users of
taxicabs within the prior four years. However, no one may




                                  18
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


recover his separate damages until he comes forward, identifies
himself and proves the amount thereof.” (Ibid.)7
         4. Subsequent decisions of this court
       Daar, supra, 67 Cal.2d 695 remains our most detailed
explication of the ascertainability requirement. In the half-
century since Daar, we have frequently mentioned the need to
show an ascertainable class as a prerequisite to certification.
(E.g., Brinker, supra, 53 Cal.4th at p. 1021; In re Tobacco II,
supra, 46 Cal.4th at p. 318; Sav-On, supra, 34 Cal.4th at p. 326;
Linder, supra, 23 Cal.4th at p. 435; Richmond, supra, 29 Cal.3d
at p. 470; Vasquez, supra, 4 Cal.3d at p. 809.) In some instances,
we have explained how the class before us satisfied this
requirement. (E.g., Richmond, at p. 478 [observing that the
members of the class “are easily identified and located”];
Vasquez, at p. 811 [noting that the names and addresses of the
approximately 200 persons in the proposed class “may be
ascertained from defendants’ books”]; Occidental Land, Inc. v.
Superior Court (1976) 18 Cal.3d 355, 360 [“class members can
be readily identified by a search of public records”].) On two
other occasions, we have referenced ascertainability in finding
no abuse of discretion in trial courts’ refusals to certify proposed

7
      Our opinion in Daar, supra, 67 Cal.2d 695 also quoted a
leading treatise’s observation that “ ‘[a] distinction is sometimes
drawn between the maintenance of the suit and its binding
effect on the absent parties. A sufficient pleading of the
conditions may withstand a demurrer and satisfy the court that
the action should proceed. But if the judgment is thereafter
collaterally attacked by an absent party, a more careful scrutiny
of its representative character may be made in determining
whether it is res judicata.’ ” (Id., at p. 706, quoting 2 Witkin,
Cal. Procedure (1954) Representative or Class Suits, § 99,
p. 1080.)


                                   19
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


classes. In both of these cases, however, there were multiple
grounds for denying class certification, which meant that our
analysis did not squarely address whether the failed class was
or was not ascertainable. (Fletcher v. Security Pacific National
Bank (1979) 23 Cal.3d 442, 448-449; Gerhard v. Stephens (1968)
68 Cal.2d 864, 912-913.)
       We have only twice offered additional explanations of
what it means for a class to be ascertainable. Both of these
descriptions were of a summary nature. In Vasquez, supra,
4 Cal.3d 800, we stated that “[a]s to the necessity for an
ascertainable class, the right of each individual to recover may
not be based on a separate set of facts applicable only to him.”
(Id., at p. 809.) More recently, the majority opinion in In re
Tobacco II, supra, 46 Cal.4th 298 characterized ascertainability
as a “preliminary step” to class certification, which requires that
a class “ ‘ “be sufficiently definite so that it is administratively
feasible for the Court to determine whether a particular
individual is a member of the proposed class.” ’ ” (Id., at p. 323,
quoting Miller v. Janssen Pharmaceutica Products, L.P. (S.D.Ill.
2007) 2007 WL 1295824, p. *5.) Class ascertainability was not
an issue before us in In re Tobacco II, however, and we had no
occasion in that case to exhaustively consider how the concept
should be understood.
      To summarize, our case law has recognized an
ascertainability requirement for class actions, but we have not
clearly articulated what this requirement entails or how it is
distinct from other prerequisites for certification — especially
the need to show a community of interest among class members.
Our decisions have also abstractly tethered class
ascertainability to due process considerations that include, but
are not necessarily limited to, the need to provide absent class

                                   20
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


members with adequate notice. But this connection has not led
to a consensus among the Courts of Appeal regarding what the
ascertainability requirement entails.
         5. The views of the Courts of Appeal regarding
            ascertainability
      Following our decision in Daar, supra, 67 Cal.2d 695, the
Courts of Appeal have developed two basic views of the
ascertainability requirement.
      One view of ascertainability concentrates on the proposed
class definition itself. This view was applied in Bartold v.
Glendale Federal Bank (2000) 81 Cal.App.4th 816 (Bartold),
superseded by statute on another point as stated in Markowitz
v. Fidelity Nat. Title Co. (2006) 142 Cal.App.4th 508, 524. The
Bartold court explained that “[a] class is ascertainable if it
identifies a group of unnamed plaintiffs by describing a set of
common characteristics sufficient to allow a member of that
group to identify himself or herself as having a right to recover
based on the description.” (81 Cal.App.4th at p. 828.) This basic
view of ascertainability has been reiterated by numerous other
Courts of Appeal, including the courts in Estrada, supra, 154
Cal.App.4th at page 14 and Aguirre, supra, 234 Cal.App.4th at
pages 1299 to 1300. (See also Aguirre, at p. 1300 [listing cases].)
A similar formulation regards a class as ascertainable when it
is defined “in terms of objective characteristics and common
transactional facts” that make “the ultimate identification of
class members possible when that identification becomes
necessary.” (Hicks, supra, 89 Cal.App.4th at p. 915.)
      The second basic view of ascertainability entails a more
exacting inquiry.       One such articulation regards the
ascertainability requirement as calling for an examination into
“(1) the class definition, (2) the size of the class and (3) the

                                  21
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


means of identifying class members.” (Miller v. Woods (1983)
148 Cal.App.3d 862, 873 (Miller); see also Noel, supra, 17
Cal.App.5th at p. 1324, Sotelo, supra, 207 Cal.App.4th at p. 648;
Reyes v. Board of Supervisors (1987) 196 Cal.App.3d 1263,
1274.) Consistent with this view, it has been said that “[c]lass
members are ‘ascertainable’ where they may be readily
identified without unreasonable expense or time by reference to
official records.” (Rose v. City of Hayward (1981) 126 Cal.App.3d
926, 932 (Rose).) On its face, the quoted language from Rose
could be understood as specifying a sufficient, as opposed to a
necessary, basis for finding an ascertainable class within the
Miller framework.8 But some courts, drawing from Rose’s focus
on the mechanics of identifying class members, have gone
further and required a class plaintiff to make a specific factual
or evidentiary showing in order to show an ascertainable class.
The Court of Appeal below, for example, regarded plaintiff as
obligated to provide proof substantiating a specific mechanism
or mechanisms through which class members could be identified


8
      The court in Rose, supra, 126 Cal.App.3d 926, ultimately
determined that “[t]he identity of the class . . . is readily
ascertainable from . . . departmental records” — a conclusion
that did not necessarily rule out other avenues for showing an
ascertainable class. (Id., at p. 932; see also Faulkinbury v. Boyd
& Associates, Inc. (2013) 216 Cal.App.4th 220, 240 [applying the
Rose standard and finding an ascertainable class]; Mora v. Big
Lots Stores, Inc. (2011) 194 Cal.App.4th 496, 504 [same];
Bomersheim v. Los Angeles Gay & Lesbian Center (2010) 184
Cal.App.4th 1471, 1481 [same]; Ghazaryan v. Diva Limousine,
Ltd. (2008) 169 Cal.App.4th 1524, 1532-1533 [same]; Lee v.
Dynamex, Inc. (2008) 166 Cal.App.4th 1325, 1334 [same]; Bufil
v. Dollar Financial Group, Inc. (2008) 162 Cal.App.4th 1193,
1206-1208 [same]; Aguiar v. Cintas Corp. No. 2 (2006) 144
Cal.App.4th 121, 135-136 [same].)


                                  22
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


so as to be personally notified of the class proceeding. (Noel,
supra, 17 Cal.App.5th at pp. 1329, 1333.) The absence of
“official” records identifying class members was central to the
analysis in Sotelo, supra, 207 Cal.App.4th 639, in which the
Court of Appeal affirmed a denial of class certification due to the
representative plaintiffs’ perceived failure to show an
ascertainable class. (Id., at p. 650.) Other Courts of Appeal, in
affirming denials of class certification on ascertainability
grounds, have emphasized that the representative plaintiff or
plaintiffs had not shown that individual class members could be
readily identified without unreasonable expense or time. (E.g.,
Cruz v. Sun World Internat., LLC (2015) 243 Cal.App.4th 367,
382; Hale v. Sharp Healthcare (2014) 232 Cal.App.4th 50, 59-
61.)
      The differences between these two basic approaches to
ascertainability can be somewhat blurred in practice. And as
previously noted, the Court of Appeal below attempted to
synthesize these views.        (Noel, supra, 17 Cal.App.5th at
p. 1329.) But as this case illustrates, a court’s choice between
the two views can be critical. A construction of ascertainability
that assigns the plaintiff in a putative class action an
affirmative responsibility to show the existence of records (or
some other mechanism or channel) through which individual
class members can be identified for the purpose of providing
them with personal notice of the proceeding may function to
defeat class certification in a variety of situations. A plaintiff
may not anticipate the need to adduce such proof at the time
class certification is sought, meaning that no precertification
discovery will have occurred on this point. This kind of
evidentiary requirement also can prevent certification when a



                                  23
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


plaintiff’s discovery efforts, albeit substantial, produce
inadequate evidence from the perspective of the court.
      An additional burden emerges when the plaintiff must
demonstrate that individual members of the proposed class can
“be readily identified without unreasonable expense or time.”
(Rose, supra, 126 Cal.App.3d at p. 932.)        With such a
requirement, class certification may be denied on
ascertainability grounds due to expected complexities in the
provision of notice, or in distinguishing class members from
nonmembers — without close consideration necessarily being
given to whether these difficulties are actual, as opposed to
merely hypothetical, or whether they are so intransigent and
pervasive that they would make a class proceeding
unmanageable, or undesirable in light of the plausible
alternatives.
          6. The views of the federal courts regarding
             ascertainability
       Federal courts have wrestled with ascertainability issues
in cases where plaintiffs have sought certification of a class under
rule 23 of the Federal Rules of Civil Procedure (28 U.S.C.).9
Although this rule does not expressly demand an ascertainable
class, most courts tasked with applying it have regarded
ascertainability as an implicit “ ‘threshold’ ” requirement for
certification of a class under Rule 23(b)(3). (Sandusky Wellness
Center v. MedTox Scientific (8th Cir. 2016) 821 F.3d 992, 995; but
see Briseno v. ConAgra Foods, Inc. (9th Cir. 2017) 844 F.3d 1121,
1124-1125, fn. 4 [“we have addressed the types of alleged
definitional deficiencies other courts have referred to as


9
     All further references to “Rule 23” and its subparts are to
the Federal Rules of Civil Procedure (28 U.S.C.).


                                   24
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


‘ascertainability’ issues . . . through analysis of Rule 23’s
enumerated requirements”].) In this context, competing views
regarding ascertainability have emerged within the federal
system, just as they have within the courts of this state.
      A stringent view of ascertainability is most closely
associated with decisions produced by the United States Court
of Appeals for the Third Circuit. (See Marcus v. BMW of North
America, LLC (3d Cir. 2012) 687 F.3d 583, 592-594 (Marcus);
Hayes v. Wal-Mart Stores, Inc. (3d Cir. 2013) 725 F.3d 349, 354-
356; Carrera v. Bayer Corp. (3d Cir. 2013) 727 F.3d 300, 305-
312.) Under this approach, a plaintiff seeking class certification
under Rule 23(b)(3) must show not only that the class has been
“defined with reference to objective criteria,” but also that there
is “a reliable and administratively feasible mechanism for
determining whether putative class members fall within the
class definition.” (Hayes, at p. 355.) Courts adopting this
conception of ascertainability have refused to certify (or upheld
refusals to certify) consumer classes in situations such as the
one presently before this court — in which it is unlikely, or at
least unproven, that individual purchasers of the commodity at
the heart of the dispute would have retained their receipts or
other proof of purchase, the defendant did not maintain a
specific list of purchasers, and the putative class representative
offered no proof when seeking certification “that a single
purchaser of [the product] could be identified using records of
customer membership cards or records of online sales.”
(Carrera, at p. 309; see id., at pp. 304, 312.)
      Other courts have pushed back on this stringent approach
to ascertainability. The United States Court of Appeals for the
Seventh Circuit is among the federal courts that assign a
narrower function to the ascertainability requirement. Its

                                  25
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


decision in Mullins v. Direct Digital, LLC (7th Cir. 2015) 795
F.3d 654 (Mullins) offers a thorough, and in our view
illuminating, assessment of how ascertainability should be
understood in connection with class certification. Because the
analysis in Mullins is particularly helpful in resolving the issue
before us, we discuss its facts and reasoning at some length
below. (See Linder, supra, 23 Cal.4th at pp. 437-439 [consulting
federal court decisions construing Rule 23 for guidance in
dealing with similar class certification issues arising under
state law].)
       The plaintiff in Mullins, supra, 795 F.3d 654, secured the
certification of a consumer class under Rule 23(b)(3) in a matter
alleging that the defendant made fraudulent representations in
marketing a dietary joint supplement. (Mullins, at p. 658.)
Drawing from the Third Circuit’s jurisprudence, the defendant
in Mullins argued on appeal of the certification order that the
class was not ascertainable because the plaintiff had “fail[ed] to
show a reliable and administratively feasible way to determine
whether a particular person is a member of the class.” (Id., at
p. 661.)
       The appellate court in Mullins, supra, 795 F.3d 654,
rejected this view of ascertainability and affirmed the class
certification order entered by the district court. (Id., at p. 658.)
In doing so, the federal court of appeals distinguished between
a     relatively    uncontroversial     “ ‘weak’     version      of
ascertainability,” and the more demanding ascertainability
standard adopted by the Third Circuit. (Id., at p. 659.) The
“ ‘weak’ ” construction of ascertainability, the court explained,
derives from “experience [that] has led courts to require that
classes be defined clearly and based on objective criteria.” (Ibid.)
Even in this weak form, Mullins elaborated, the requirement of

                                   26
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


a clearly defined class based on objective criteria is far from
toothless, for it serves to weed out “classes that are defined too
vaguely” (ibid.), “classes that are defined by subjective criteria,
such as by a person’s state of mind” (id., at p. 660), and “classes
that are defined in terms of success on the merits — so-called
‘fail-safe classes’ ” (ibid.), all of which raise due process or other
fairness concerns. The Mullins court regarded this approach to
ascertainability as striking an appropriate balance, whereas the
Third Circuit’s more exacting conception of this requirement did
not. In the view of the Mullins court, the more demanding
specification “does not further any interest of Rule 23 that is not
already adequately protected by the Rule’s explicit
requirements. On the other side of the balance, the costs of
imposing the requirement are substantial. The stringent
version of ascertainability effectively bars low-value consumer
class actions, at least where plaintiffs do not have documentary
proof of purchases, and sometimes even when they do.” (Id., at
p. 662.)
       Mullins, supra, 795 F.3d 654 then proceeded to dissect the
specific policy arguments advanced for the Third Circuit’s
construction of the ascertainability requirement. (Id., at pp.
663-672.) One such contention was that the “stringent version
of ascertainability ‘eliminates serious administrative burdens
that are incongruous with the efficiencies expected in a class
action by insisting on the easy identification of class members.’ ”
(Id., at p. 663, quoting Marcus, supra, 687 F.3d at p. 593.) The
Mullins court saw this concern as “better addressed by the
explicit requirements of Rule 23(b)(3), which requires that the
class device be ‘superior to other available methods for fairly and
efficiently adjudicating the controversy,’ ” with one
consideration relevant to the superiority inquiry being “ ‘the


                                   27
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


likely difficulties in managing a class action.’ ”            (Mullins,
quoting Rule 23(b)(3), (b)(3)(D).)
      Mullins, supra, 795 F.3d 654 explained why it made more
sense to address within the context of manageability any
concerns about the burdens that could be associated with the
identification of class members: “When administrative
inconvenience is addressed as a matter of ascertainability,
courts tend to look at the problem in a vacuum, considering only
the administrative costs and headaches of proceeding as a class
action. [Citation.] But when courts approach the issue as part
of a careful application of Rule 23(b)(3)’s superiority standard,
they must recognize both the costs and benefits of the class
device. [Citation.] [¶] . . . In many cases where the heightened
ascertainability requirement will be hardest to satisfy, there
realistically is no other alternative to class treatment.” (Id., at
pp. 663-664.) The court in Mullins cautioned that “[t]his does
not mean . . . that district courts should automatically certify
classes in these difficult cases,” and granted that “[i]f faced with
what appear to be unusually difficult manageability problems
at the certification stage, district courts have discretion to insist
on details of the plaintiff’s plan for notifying the class and
managing the action.” (Id., at p. 664.) Yet, the court continued,
judges who encounter such challenges should attempt to
leverage their “experience with and flexibility in engineering
solutions to difficult problems of case management,” and
“refusing to certify on manageability grounds alone should be
the last resort.” (Ibid.)
     The court in Mullins, supra, 795 F.3d 654 also addressed
an argument that resonated with the Court of Appeal in this
case — “that the heightened ascertainability requirement is
needed to protect absent class members. If the identities of

                                   28
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


absent class members cannot be ascertained, the argument
goes, it is unfair to bind them by the judicial proceeding.” (Id., at
p. 665.) It perceived that “[a] central premise of this argument
is that class members must receive actual notice of the class
action so that they do not lose their opt-out rights.” (Ibid.)
       The court in Mullins, supra, 795 F.3d 654 regarded this
premise as mistaken. It emphasized that, when a class has been
certified under Rule 23(b)(3), Rule 23(c)(2)(B) requires the
provision of the “ ‘best notice that is practicable under the
circumstances, including individual notice to all members who
can be identified through reasonable effort’ ” — language
connoting that individual notice need not be given to members
who cannot be so identified. (Mullins, at p. 665.)10 Nor, in the
court’s view, did principles of due process invariably require
individual notice to absent class members. Instead, in cases
such as the one before it, “When class members’ names and
addresses are known or knowable with reasonable effort, notice
can be accomplished by first-class mail. [Citation.] When that
is not possible, courts may use alternative means such as notice
through third parties, paid advertising, and/or posting in places




10
      With classes certified under Rule 23(b)(1) or (2),
meanwhile, the federal rules provide more generally that “the
court may direct appropriate notice to the class.” (Id., Rule
23(c)(2)(A).)



                                   29
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


frequented by class members, all without offending due
process.” (Ibid.)11
      Mullins, supra, 795 F.3d 654 also explained why
construing the ascertainability requirement as anticipating
personal notice in all cases could provide absent class members
with a pyrrhic victory. “More broadly,” the court wrote, “the
stringent version of ascertainability loses sight of a critical
feature of class actions for low-value claims like this one. In
these cases, ‘only a lunatic or a fanatic’ would litigate the claim
individually, [citation], so opt-out rights are not likely to be
exercised by anyone planning a separate individual lawsuit.
When this is true, it is particularly important that the types of
notice that courts require correspond to the value of the absent
class members’ interests. [Citation.] . . . . [¶] The heightened
ascertainability approach upsets this balance. It comes close to
insisting on actual notice to protect the interests of absent class
members, yet overlooks the reality that without certification,
putative class members with valid claims would not recover
anything at all.” (Id., at pp. 665-666.)



11
       Mullins, supra, 795 F.3d 654 also rejected the argument
that a heightened ascertainability requirement was necessary
to protect the due process interests of class action defendants by
protecting them from bogus claims and disproportionate
liability. (Id., at pp. 669-672.) These concerns do not resonate
here, in any event. There is no suggestion that, if the plaintiff
class ultimately prevails, Rite Aid will face any onslaught of
spurious claims, much less a bevy that could not be weeded out
through a competent claims administration process. Also,
because it is known how many pools were sold and not returned,
and how much in revenue Rite Aid earned from these sales, the
overall body of claims has a functional ceiling that further
marginalizes any prospect of exaggerated liability.


                                  30
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


     C.    Analysis
          1. An ascertainable class is one defined in objective
             terms that make the eventual identification of class
             members possible
      Although Mullins, supra, 795 F.3d 654 applied only
federal law, much of its analysis rings true here as well. We
agree with Mullins’ assignment of a limited but important
function to the ascertainability requirement. We conclude that
the objectives of this requirement are best achieved by regarding
a class as ascertainable when it is defined “in terms of objective
characteristics and common transactional facts” that make “the
ultimate identification of class members possible when that
identification becomes necessary.”           (Hicks, supra, 89
Cal.App.4th at p. 915.) We regard this standard as including
class definitions that are “sufficient to allow a member of [the
class] to identify himself or herself as having a right to recover
based on the [class] description.”          (Bartold, supra, 81
Cal.App.4th at p. 828.)
      This understanding of the threshold requirement of
ascertainability for class certification protects the due process
interests of all parties and absent class members without
unduly impairing the efficacy of the class action mechanism. We
have explained some of the benefits that class proceedings such
as the one at bar can yield: “Not only do class actions offer
consumers a means of recovery for modest individual damages,
but such actions often produce ‘several salutary by-products,
including a therapeutic effect upon those sellers who indulge in
fraudulent practices, aid to legitimate business enterprises by
curtailing illegitimate competition, and avoidance to the judicial
process of the burden of multiple litigation involving identical




                                  31
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


claims.’ ” (Linder, supra, 23 Cal.4th at p. 445, quoting Vasquez,
supra, 4 Cal.3d at p. 808; see also Vasquez, at p. 807.)
       But a class proceeding must be maintained in a manner
consistent with due process. A class definition framed in
objective terms that make the identification of class members
possible promotes due process in at least two ways. Such
phrasing puts members of the class on notice that their rights
may be adjudicated in the proceeding, so they must decide
whether to intervene, opt out, or do nothing and live with the
consequences. (See Hicks, supra, 89 Cal.App.4th at p. 914
[“[a]scertainability is required in order to give notice to putative
class members as to whom the judgment in the action will be res
judicata”].) This kind of class definition also advances due
process by supplying a concrete basis for determining who will
and will not be bound by (or benefit from) any judgment.
Allowing a class to be defined in vague terms, by contrast, could
blunt any invocation of res judicata by the defendant in
subsequent lawsuits brought by persons attempting to relitigate
issues decided in the earlier class proceeding. The outcome
might resemble that which obtains when the “one-way
intervention” condemned by our decision in Fireside Bank v.
Superior Court (2007) 40 Cal.4th 1069, 1078 (Fireside Bank)
occurs — the defendant could be unfairly exposed to a succession
of essentially duplicative class lawsuits (see id., at pp. 1078-
1083).12


12
      The ascertainability standard we endorse also addresses
similar fairness concerns that may be associated with other
problematic class definitions, such as a class defined by its
putative members’ subjective states of mind, as opposed to



                                   32
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


      The Court of Appeal saw a slightly different set of due
process considerations as favoring a more stringent approach to
ascertainability.     It expressed concern that, without an
evidentiary showing by plaintiff, absent class members would
never receive notice of the action and would therefore lack the
opportunity to opt out. To this effect, the Court of Appeal quoted
Sotelo, supra, 207 Cal.App.4th at page 649: “ ‘The theoretical
ability to self-identify as a member of the class is useless if one
never receives notice of the action.’ ”         (Noel, supra, 17
Cal.App.5th at p. 1327.) We appreciate the court’s interest in
protecting the due process rights of absent class members. Yet,
as we explain below, this concern does not justify the evidentiary
burden that the Court of Appeal attached to the ascertainability
requirement — or, for that matter, any blanket requirement
that class members must be identifiable “by reference to official
records” (Rose, supra, 126 Cal.App.3d at p. 932) to form an
ascertainable class.
      We agree, of course, that the provision of notice to absent
class members carries due process connotations. (See Phillips
Petroleum Co. v. Shutts (1985) 472 U.S 797, 811 (Shutts);
Fireside Bank, supra, 40 Cal.4th at p. 1083.) But due process
does not dictate that certification of a putative plaintiff class
invariably must depend on all absent class members being sent
(much less receiving) individual notice of the action. Instead,



objective facts. (See 1 Newberg on Class Actions (5th ed. 2011)
§ 3:5, p. 168 [“[c]ourts generally deny certification when the
putative class is defined by class members’ state of mind”]; see
also Mullins, supra, 795 F.3d at p. 660; Simer v. Rios (7th
Cir.1981) 661 F.2d 655, 669-670.)



                                  33
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


the law adopts a more nuanced and pragmatic approach,
consistent with the general principle that when an important
judicial mechanism for advancing the social good is involved, “A
construction of the Due Process Clause which would place
impossible or impractical obstacles in the way could not be
justified.” (Mullane v. Central Hanover Tr. Co. (1950) 339 U.S.
306, 313-314 (Mullane).)
       Mullane, supra, 339 U.S. 306 provides the touchstone for
assessing how due process informs the provision of notice in the
context of a class action. The court in Mullane recognized that
“[a]n elementary and fundamental requirement of due process
in any proceeding which is to be accorded finality is notice
reasonably calculated, under all the circumstances, to apprise
interested parties of the pendency of the action and afford them
an opportunity to present their objections. [Citations.] The
notice must be of such nature as reasonably to convey the
required information, [citation], and it must afford a reasonable
time for those interested to make their appearance [citations].”
(Id., at p. 314.) Significantly, the court drew the following line:
“But if with due regard for the practicalities and peculiarities of
the case these conditions are reasonably met, the constitutional
requirements are satisfied. ‘The criterion is not the possibility
of conceivable injury but the just and reasonable character of
the requirements, having reference to the subject with which the
statute deals.’ ” (Id., at pp. 314-315.)
      Applying these principles, the court in Mullane, supra,
339 U.S. 306 reasoned that in connection with a particular
judicial settlement of accounts, notice by personal mail was
required for beneficiaries whose identities and mailing
addresses were actually known. (Id., at p. 318.) Yet, “in view of
the character of the proceedings and the nature of the interests”

                                  34
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


involved, notice by publication would suffice for those
beneficiaries “whose interests or whereabouts could not with
due diligence be ascertained.” (Id., at p. 317.) Likewise, “more
certain notice” could be dispensed with for those beneficiaries
“whose interests are either conjectural or future or, although
they could be discovered upon investigation, do not in due course
of business come to knowledge of the common trustee.” (Ibid.)
This notice scheme was “the best practicable, ‘reasonably
calculated, under all the circumstances, to apprise interested
parties of the pendency of the action and afford them an
opportunity to present their objections.’ ” (Shutts, supra, 472
U.S. at p. 812, quoting Mullane, at pp. 314-315, italics added.)
      Our case law has adopted a similarly practical approach,
in which the circumstances of each case determine what forms
of notice will adequately address due process concerns. (See
Linder, supra, 23 Cal.4th at p. 444 [describing the notice inquiry
as entailing due consideration of “the necessity, feasibility and
costs of any particular form of notice”].) Recall that in Daar,
supra, 67 Cal.2d 695, examined ante, we found the allegations
in the complaint sufficient to state a viable class even as to
taxicab customers who paid in cash, for whom the prospect of
individualized notice was far-fetched at best. (Id., at p. 714.) In
doing so, we disavowed any “necessity of identifying the
individual members of such class as a prerequisite to a class
suit. If the existence of an ascertainable class has been shown,
there is no need to identify its individual members in order to
bind all members by the judgment.” (Id., at p. 706.) We then
added, “The fact that the class members are unidentifiable at
this point will not preclude a complete determination of the
issues affecting the class.”            (Ibid., italics added.)
“Unidentifiable” means more than just unidentified. Our use of


                                  35
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


the former term conveyed that in a case such as Daar, due
process does not demand that the proponent of class treatment
demonstrate, as a prerequisite for certification, that (much less
how) class members eventually will receive individual notice of
the action.
      Since then, we have observed that individual notice may
not always be required even for absent class members whose
whereabouts are known, explaining “the representative plaintiff
in a California class action is not required to notify individually
every readily ascertainable member of his class without regard
to the feasibility of such notice; he need only provide meaningful
notice in a form that ‘should have a reasonable chance of
reaching a substantial percentage of the class members.’ ”
(Archibald v. Cinerama Hotels (1976) 15 Cal.3d 853, 861,
quoting Cartt v. Superior Court (1975) 50 Cal.App.3d 960, 974;
compare Rule 23(c)(2)(B) [upon certifying a class under Rule
23(b)(3), “the court must direct to class members the best notice
practicable under the circumstances including individual notice
to all members who can be identified through reasonable
effort”].) One Court of Appeal has elaborated that “when the
membership of the class is huge, the damages are minimal, and
res judicata and . . . other problems . . . are insignificant, notice
by publication is adequate.” (Cooper v. American Sav. & Loan
Assn. (1976) 55 Cal.App.3d 274, 285.)
      The pertinent statutes and California Rules of Court are
in accord. With claims brought as putative class actions under
the CLRA, “If the action is permitted as a class action, the court
may direct either party to notify each member of the class of the
action. The party required to serve notice may, with the
consent of the court, if personal notification is unreasonably
expensive or it appears that all members of the class cannot be

                                   36
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


notified personally, give notice as prescribed herein by
publication in accordance with Section 6064 of the Government
Code in a newspaper of general circulation in the county in
which the transaction occurred.” (Civ. Code, § 1781, subd. (d).)
In the same spirit, the Rules of Court prescribe an array of
considerations for determining the form or forms of notice that
should be provided to a certified class. Pursuant to rule 3.766(e)
of the California Rules of Court, “In determining the manner of
the notice [to class members], the court must consider: [¶]
(1) The interests of the class; [¶] (2) The type of relief requested;
[¶] (3) The stake of the individual class members; [¶] (4) The cost
of notifying class members; [¶] (5) The resources of the parties;
[¶] (6) The possible prejudice to class members who do not
receive notice; and [¶] (7) The res judicata effect on class
members.” The rules of court also provide that “[i]f personal
notification is unreasonably expensive or the stake of individual
class members is insubstantial, or if it appears that all members
of the class cannot be notified personally, the court may order a
means of notice reasonably calculated to apprise the class
members of the pendency of the action — for example,
publication in a newspaper or magazine; broadcasting on
television, radio, or the Internet; or posting or distribution
through a trade or professional association, union, or public
interest group.” (Id., rule 3.766(f), italics added.)
       To summarize, due process does not invariably require
that personal notice be directed to all members of a class in order
for a class action to proceed, or for that matter that an individual
member of a certified class must receive notice to be bound by a
judgment. (See Juris v. Inamed Corp. (11th Cir. 2012) 685 F.3d
1294, 1321 [citing cases]; 7AA Wright et al., Federal Practice &
Procedure (3d ed. 2005) § 1789.1, p. 571.) It follows that a


                                   37
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


construction of the ascertainability requirement that presumes
such notice is necessary to satisfy due process, and demands
that the plaintiff show how it can be accomplished, threatens to
demand too much, too soon. It is likewise mistaken to take a
categorical view that the relevant due process interests can be
satisfied only when “official records” (Rose, supra, 126
Cal.App.3d at p. 932) supply the means of identifying class
members, and for a similar reason: due process is not that
inflexible.13
      The Court of Appeal below recognized the possibility that
due process might not require individual notice to absent class
members in all circumstances. As recounted ante, the Court of
Appeal noted that the court in Aguirre, supra, 234 Cal.App.4th
1290 had declined to require such notice to consumers within
the plaintiff class. (Noel, supra, 17 Cal.App.5th at p. 1331.) It
distinguished Aguirre on the ground that the class in that case
was much larger than the proposed class is here. (Noel, at
p. 1331.) We believe the point is more fundamental: As a rule,
a representative plaintiff in a class action need not introduce
evidence establishing how notice of the action will be
communicated to individual class members in order to show an
ascertainable class.
      This bright-line rule maintains the straightforward
nature of what is properly understood as a threshold
requirement for class certification, and allows for the relevant

13
      As a somewhat distinct point, we also observe that
premising ascertainability on the existence of official records
capable of being used to identify class members might, in some
situations, incentivize potential class action defendants to
destroy or refuse to maintain useful records that could provide
a basis for class treatment.


                                  38
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


due process interests to be more sensitively calibrated and
addressed through other mechanisms.               As shown, the
development of a notice plan that comports with due process
implicates a diverse array of considerations. (See Cal. Rules of
Court, rule 3.766(f); Linder, supra, 23 Cal.4th at pp. 444, 446.)
Some of the facts relevant to the development of a
constitutionally adequate notice plan normally will not be
immediately obvious from the class definition itself. Regardless
of the size of the class or other relevant circumstances, a demand
that the representative plaintiff show how individualized notice
could be provided to class members in order to establish an
ascertainable class could preempt a more careful, nuanced, and
potentially collaborative assessment, and in doing so impose
upon the plaintiff an absolute requirement that closer review of
all of the relevant facts could demonstrate to be excessive in
light of the interests involved.
      This case illustrates the problem. The record before us
does not establish all of the facts and circumstances relevant to
a determination regarding the appropriate form or forms of
notice to the class. Yet the record casts substantial doubt on the
proposition that due process can be satisfied only through the
provision of individual notice to the approximately 20,000
members of the putative class. For one thing, these purchasers
may not be reasonably identifiable. Meanwhile, given the
modest amount at stake (the pool having retailed for $59.99),
the odds that any class member will bring a duplicative
individual action in the future are effectively zero. Thus the
true choice in this case is not between a single class action
challenging the packaging of the Ready Set Pool and multiple
individual actions pressing similar claims; it is between a class
action and no lawsuits being brought at all. Under the


                                  39
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


circumstances, due process may not demand personal notice to
individual class members, and to build a contrary assumption
into the ascertainability requirement would be a mistake.14
       Reading into the ascertainability element an additional
requirement that the identification of class members must occur
“ ‘without unreasonable expense or time’ ” (Sotelo, supra, 207
Cal.App.4th at p. 648) runs a similar risk of preempting a more
careful analysis later. Our jurisprudence addressing class
certification has stressed the importance of a careful weighing
of both the benefits and the burdens that may be associated with
a proposed class action. (See, e.g., Linder, supra, 23 Cal.4th at
pp. 445-446.) A conception of ascertainability as concerned with
whether class members can be identified without an
unreasonable commitment of expense or time is at cross
purposes with this direction. As the court in Mullins supra,
795 F.3d at pages 663 to 664 explained in rejecting a similar
expansion of the ascertainability requirement, such an approach
trains the court’s attention, at a threshold juncture, exclusively
toward the side of the ledger where costs and challenges are
compiled. This focus means that full attention will not
necessarily be given to countervailing considerations — such as
whether these difficulties, although present, might nevertheless
be effectively managed through application of the various tools
and resources courts have at their disposal for effective


14
      To be clear, we have no occasion at this time to decide
precisely what would constitute adequate notice to absent
members of the proposed class in this case. Presumably, after
remand any and all appropriate inquiries will be made into
matters relevant to the provision of adequate notice.



                                  40
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


supervision of a class proceeding, and whether, notwithstanding
possible notice issues, an appropriately supervised class action
nevertheless can be expected to deliver benefits that, from a
comparative perspective, would make it preferable to
alternative courses of action.15




15
       Numerous decisions by the Courts of Appeal, in addition
to the opinion below, have invoked and applied the standard for
ascertainability originally set forth in Rose v. City of Hayward,
supra, 126 Cal.App.3d at page 932, providing that “[c]lass
members are ‘ascertainable’ where they may be readily
identified without unreasonable expense or time by reference to
official records.” (See Hefczyc v. Rady Children’s Hospital-San
Diego (2017) 17 Cal.App.5th 518, 536-540; Kendall v. Scripps
Health (2017) 16 Cal.App.5th 553, 574-575; Cruz v. Sun World
Internat., LLC, supra, 243 Cal.App.4th at pp. 375-382; Hale v.
Sharp Healthcare, supra, 232 Cal.App.4th at pp. 58-61;
Thompson v. Automobile Club of Southern California, supra,
217 Cal.App.4th at pp. 728-731; Faulkinbury v. Boyd &
Associates, Inc., supra, 216 Cal.App.4th at p. 240; Sotelo v.
MediaNews Group, Inc., supra, 207 Cal.App.4th at pp. 648-650;
Mora v. Big Lots Stores, Inc., supra, 194 Cal.App.4th at p. 504;
Bomersheim v. Los Angeles Gay & Lesbian Center, supra, 184
Cal.App.4th at p. 1481; Ghazaryan v. Diva Limousine, Ltd.,
supra, 169 Cal.App.4th at pp. 1532-1533; Lee v. Dynamex, Inc.,
supra, 166 Cal.App.4th at p. 1334; Bufil v. Dollar Financial
Group, Inc., supra, 162 Cal.App.4th at pp. 1206-1208; Aguiar v.
Cintas Corp. No. 2, supra, 144 Cal.App.4th at pp. 135-136.) As
our analysis should make clear, this is one way but not the only
way to show an ascertainable class. We therefore disapprove of
this standard insofar as it could be perceived as exclusive.
Likewise, insofar as the three-factor approach to
ascertainability set forth in Miller, supra, 148 Cal.App.3d at
page 873 could be read to demand a more exacting inquiry than
the approach we endorse today, we disapprove of it, as well.



                                  41
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


      Our view of the ascertainability requirement does not
prohibit a court asked to certify a class from considering the
separate question of notice to absent class members. Arguments
and evidence relating to the provision of notice to the class
conceivably could counsel against class certification insofar as
they may show that another requirement for a proper class
proceeding, aside from ascertainability, has not been met — e.g.,
that a class action would be unmanageable, even after due
consideration is given to how manageability concerns could be
resolved; or that a class proceeding would not be superior to the
alternatives. (Accord, Mullins, 795 F.3d at p. 664 [“If faced with
what appear to be unusually difficult manageability problems
at the certification stage, district courts have discretion to insist
on details of the plaintiff’s plan for notifying the class and
managing the action.”].)16 But, at the risk of repetition, we
conclude that these issues, where they exist, are appropriately
addressed outside of and separately from the ascertainability
requirement.
         2. The trial court abused its discretion when it found no
            ascertainable class existed
      It follows from the analysis above that the trial court erred
when it determined that the class proposed by plaintiff is not
ascertainable. It is. The phrasing, “All persons who purchased

16
      Even though class definition is logically antecedent to the
question of how notice is to be provided to the class (see Fireside
Bank, supra, 40 Cal.4th at p. 1074; Home Savings & Loan Assn.
v. Superior Court (1974) 42 Cal.App.3d 1006, 1010) and notice
is commonly addressed after class certification (see, e.g., Linder,
supra, 23 Cal.4th at p. 444), contemporaneous inquiries into
both class definition and notice are permissible under the CLRA
(see Civ. Code, § 1781, subd. (c)(1), (2)) and the rules of court
(Cal. Rules of Court, rule 3.766(c)).


                                   42
                  NOEL v. THRIFTY PAYLESS, INC.
              Opinion of the Court by Cantil-Sakauye, C. J.


the Ready Set Pool at a Rite Aid store located in California
within the four years preceding the date of the filing of this
action” is neither vague nor subjective. A member of the class
could appreciate from this definition whether he or she is
included within it, and thus be in a position to take appropriate
steps to protect his or her interests. And the definition makes
the res judicata consequences of a judgment clear, creating no
ambiguity as to who will and will not be bound by the outcome.
(See Daar, supra, 67 Cal.2d at p. 706.)17
      To the extent that the trial court had concerns regarding
the state of the record as it pertained to matters such as the
provision of notice to class members, or how burdensome it
would be to identify class members, those issues should not have
been resolved in the context of ascertainability. And regardless
of whether plaintiff’s failure to supply evidence associated with
the identification of class members might have supported a
refusal to certify a class on some other ground (but cf. Daar,
supra, 67 Cal.2d at p. 706), it manifestly did not justify a failure
to find an ascertainable class. Our review ends there. (See
Linder, supra, 23 Cal.4th at p. 436.)
                         III. DISPOSITION
       As noted ante, the trial court denied the motion for class
certification in its entirety on ascertainability grounds. That

17
      The record developed below does not establish whether
Rite Aid sold Ready Set Pools in other sizes during the class
period. If so, the class definition’s reference to purchasers of “the
Ready Set Pool” (italics added) may require clarification, to
establish that only purchasers of the model measuring eight feet
by 25 inches are included within the class. This flaw within the
definition would not, however, mean that the class is not
ascertainable.


                                   43
                 NOEL v. THRIFTY PAYLESS, INC.
             Opinion of the Court by Cantil-Sakauye, C. J.


court also denied certification of the proposed CLRA class on the
basis that common issues did not predominate. Because we do
not address the latter aspect of the trial court’s ruling here,
overturning its ascertainability determination would not, by
itself, make a CLRA class viable. The trial court also offered a
third justification for denying class certification that was
ambiguous in its scope. It is unclear whether the trial court had
only the proposed CLRA class in mind when it determined that
a class action would not be superior to the alternatives, or
whether this conclusion applied to the entirety of the action. It
also cannot be discerned from this vantage point whether the
court’s erroneous view of ascertainability informed its analysis
on this issue. Because of these uncertainties, we reverse the
judgment below and remand the case to the Court of Appeal
with directions to remand the matter to the superior court for
further proceedings consistent with our decision.
                                       CANTIL-SAKAUYE, C. J.


We Concur:
CHIN, J.
CORRIGAN, J.
LIU, J.
CUÉLLAR, J.
KRUGER, J.
GROBAN, J.




                                  44
See next page for addresses and telephone numbers for counsel who argued in Supreme Court.

Name of Opinion Noel v. Thrifty Payless, Inc.
__________________________________________________________________________________

Unpublished Opinion
Original Appeal
Original Proceeding
Review Granted XXX 17 Cal.App.5th 1315
Rehearing Granted

__________________________________________________________________________________

Opinion No. S246490
Date Filed: July 29, 2019
__________________________________________________________________________________

Court: Superior
County: Marin
Judge: Paul M. Haakenson

__________________________________________________________________________________

Counsel:

Emergent Legal, Emergent, Christopher Wimmer, Peter Roldan; Public Justice, Leslie Brueckner and Karla
Gilbride for Plaintiff and Appellant.

Chavez & Gertler, Mark A. Chavez; Public Citizen Ligation Group and Allison M. Zieve for Public Citizen
as Amicus Curiae on behalf of Plaintiff and Appellant.

Rock Law, Matt J. Malone; Nelson & Fraenkel, Gretchen M. Nelson; Arbogast Law and David M.
Arbogast for Consumer Attorneys of California as Amicus Curiae on behalf of Plaintiff and Appellant.

Lieff Cabraser Heimann & Bernstein, Robert J. Nelson, Roger N. Heller and Melisa Gardner for National
Consumer Law Center and National Association of Consumer Advocates as Amici Curiae on behalf of
Plaintiff and Appellant.

Jocelyn D. Larkin and Daniel Nesbit for Impact Fund, California Employment Lawyers Association,
Centro Legal de la Raza, Legal Aid at Work and Worksafe as Amici Curiae on behalf of Plaintiff and
Appellant.

Kelly, Hockel & Klein, Klein, Hockel, Iezza & Patel, Michael D. Early and Mark P. Iezza for Defendant
and Respondent.

Utrecht & Lenvin and Paul F. Utrecht for Washington Legal Foundation and California Retailers
Association as Amici Curiae on behalf of Defendant and Respondent.
Counsel who argued in Supreme Court (not intended for publication with opinion):

Leslie Brueckner
Public Justice
475 14th Street, Suite 610
Oakland, CA 94612
(510) 622-8205

Michael D. Early
Klein, Hockel, Iezza & Patel
455 Market Street, Suite 1480
San Francisco, CA 94105
(415) 951-0535
