United States Court of Appeals

FOR THE EIGHTH CIRCUIT

___________

No. 10-2267

___________

In re: Zurn Pex Plumbing *

Products Liability Litigation *

_______________________ *

*

Denise Cox; Terry Cox; Kevin Haugen; *

Christa Haugen; Robert Hvezda; *

Carrie Hvezda; Jody Minnerath; *

Brian Minnerath; Michelle Oelfke, *

on behalf of themselves and all others *

similarly situated, * Appeal from the United States

* District Court for the

 Plaintiffs - Appellees, * District of Minnesota.

*

v. *

*

Zurn Pex, Inc.; Zurn Industries, Inc., *

*

Defendants - Appellants. *

_______________________ *

*

American Association for Justice, *

*

 Amicus Curiae. *

___________

Submitted: March 16, 2011

Filed: July 6, 2011

___________

Before WOLLMAN, MURPHY, and GRUENDER, Circuit Judges.

___________
1

This action only involves claims by Minnesota homeowners. Claims filed by

plaintiffs in other states have also been consolidated in the District of Minnesota for

pretrial proceedings by the Judicial Panel on Multidistrict Litigation. See 28 U.S.C.

§ 1407. 

2

The Honorable Ann D. Montgomery, United States District Judge for the

District of Minnesota.

-2-

MURPHY, Circuit Judge.

Minnesota homeowners brought this action1

 against Zurn Pex, Inc. and Zurn

Industries, Inc (Zurn) alleging that brass fittings used in the company's cross linked

polyethylene (PEX) plumbing systems are inherently defective. In pretrial motions

the homeowners sought class certification for their consumer protection, warranty, and

negligence claims, and Zurn moved to strike the testimony of two of the homeowners’

experts. After denying Zurn's motion to strike the expert testimony, the district court2

granted the homeowner requests for class certification for their warranty and

negligence claims, but denied it for their consumer protection claims. Zurn appeals

from the district court's certification order. We affirm. 

I.

Zurn manufactures and markets a home plumbing system that uses PEX tubing,

an alternative to traditional copper water pipes. PEX tubing systems are marketed as

easier to install, cheaper, and longer lasting than copper plumbing systems. The Zurn

PEX systems have been installed in homes throughout the United States. Zurn has

sold its PEX systems with a 25 year limited warranty. 

In the plumbing systems at issue in this case, PEX tubes are joined together

using a brass fitting and crimp. A tube is placed around a fitting, the crimp is

tightened around the outside of the tube, and the resulting pressure creates a seal

between the tube and the fitting. The homeowners allege that the brass fittings used
-3-

in these systems are "doomed to leak within warranty" because of their susceptibility

to stress corrosion cracking (SCC) which results from a combination of pressure and

corrosion. The homeowners argue that SCC inevitably begins to affect Zurn's brass

fittings upon their installation and exposure to water. The SCC increases over time

and the fitting eventually begins to leak, causing costly water damage to homes. Zurn

argues that SCC is not an inherent defect and that it is instead caused by a variety of

factors which include improper installation and overly corrosive water. Some of the

homeowner plumbing systems have leaked, but others have not. 

The parties disagreed about pretrial discovery. The homeowners sought a

single phase discovery plan, but Zurn suggested bifurcated discovery. The district

court adopted Zurn's approach and ordered that the first phase of discovery address

the limited question of class certification. At the close of the first phase of discovery,

the homeowners moved for class certification. Zurn opposed it and moved to strike

testimony from two of the homeowners’ experts, Dr. Roger W. Staehle and Dr.

Wallace R. Blischke.

Dr. Staehle is the former Dean of the University of Minnesota Institute of

Technology. He has been researching and publishing articles on SCC for over 40

years. Dr. Staehle examined Zurn brass fittings, including some which had leaked as

well as some which were new. He conducted a battery of tests on the fittings. His

tests included scanning electron microscopy, electron dispersive spectroscopy, auger

electron dispersive spectroscopy, microhardness testing, materials analysis, water

chemistry analysis, and static load testing. He also performed a "U-bend" experiment

where metal samples from the fittings were bent into a U shape and then tested to

determine their susceptibility to SCC. Dr. Staehle subjected these samples to strain,

immersed them in different water solutions, and then checked them after two, four,

and six months. He concluded that his experiments showed that "rapid SCC would

occur" in Zurn's brass fittings. 
-4-

Based on his knowledge about SCC and his numerous tests, Dr. Staehle

concluded that "[t]he failure process in Zurn fittings starts as soon as they are exposed

to domestic water," "[s]ignificant numbers of leak-causing failures appear to occur in

as little as a single year," and "[t]here is no evidence . . . that the Zurn fittings can

perform reliably for 25 years . . . nor are there any bases for a much longer design life

of about 40 years." Dr. Staehle attributed the poor performance of the fittings to

choice of materials and to poor manufacturing. He rejected the theory that the SCC

in Zurn's fittings was caused by unusually corrosive water or improper installations.

Dr. Blischke is a statistician and Professor Emeritus at the University of

Southern California. He has written a number of books on product reliability and

warranties. Dr. Blischke undertook a study of Zurn PEX plumbing systems and

analyzed the failure rate of those systems with Zurn's brass fittings. He grounded his

analysis on the available warranty data obtained from Zurn. Since he found that data

incomplete, he was required to make assumptions about the "mean time to failure"

experienced by the brass fittings.

Based on witness testimony and documents indicating that Zurn considered 40

years to be the average lifetime of its PEX systems, Dr. Blischke assumed a mean time

to failure of 40 years. Using that figure and assuming that the average household

installation contained 50 brass fittings, he calculated that 99% of homes would

experience a leak in at least one of the fittings within 25 years. Dr. Blischke also

conducted the same analysis based on alternate mean time to failure figures of 50, 60,

and 100 years. The system failure rates remained high even when the longer mean

time to failure figures were projected.

The parties disagreed about the appropriate application of Daubert v. Merrill

Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993), at the class certification stage. The

homeowners urged that expert testimony should only be excluded at this stage if it

were "so flawed it cannot provide any information as to whether the requisites of class
3

The district court amended the class definition proposed by the homeowners

by adding the word "Zurn" to clarify that members of the class must have a plumbing

system with Zurn brass crimp fittings.

-5-

certification have been met." Zurn argued, however, that the district court should

conduct a full and conclusive Daubert inquiry before certifying a class.

The district court charted a middle course between the positions urged by the

parties. After reviewing the evidence that had been produced, the court concluded that

a full and conclusive Daubert inquiry would not be necessary or productive at this

stage of the litigation, particularly since the expert opinions could change during

continued discovery. The court instead conducted a focused Daubert inquiry to assess

whether the opinions of Dr. Staehle and Dr. Blischke, based on their areas of expertise

and the reliability of their analyses of the available evidence, should be considered in

deciding the issues relating to class certification.

After conducting its focused Daubert inquiry, the district court denied Zurn's

motions to strike the testimony of the experts. The court made clear, however, that

its rulings were not final and that its view of the issues might change as discovery

continued and additional evidence was produced.

The district court then turned to the question of class certification under Fed.

R. Civ. P. 23. The homeowner claims fell into three broad categories: consumer

protection, breach of warranty, and negligence. For each claim, the homeowners

moved to certify the following class:

All persons and entities that own a structure located within the State of

Minnesota that contains a Zurn Pex plumbing system with Zurn3

 brass

crimp fittings. The proposed class includes, without limitation, all such

persons or entities who contacted Zurn or its representatives about their

Zurn Pex plumbing system and were denied or partially denied warranty
-6-

coverage for failure of the Zurn Pex plumbing system based on a claim

that “corrosion” was not covered by the warranty or that other alleged

warranty limitations applied.

This definition was used by the district court to analyze the Rule 23 class

certification requirements with respect to the three categories of homeowner claims.

It focused on what it termed the "core dispute between the parties" which arose out of

Rule 23(b)(3)'s requirement that questions of law or fact common to the class

predominate over individual questions. The court first determined that the issue of

individual reliance in respect to the consumer protection claims was not amenable to

class wide resolution. It refused to certify a class for those claims, and no one has

appealed that decision. The court next addressed the warranty claims, determined that

common questions predominate as to them, and certified a class of warranty claimants.

Finally, the court certified a limited class for the negligence claims. It limited the

scope of that class to those members who had already "suffered damage to their

property," that is those who already had suffered an injury recognized in tort.

Zurn brings this Rule 23(f) interlocutory appeal of the order issued by the

district court certifying the warranty and negligence classes. Zurn argues that the

district court should have excluded the expert opinions of Dr. Staehle and Dr.

Blischke and that it erred in declining to conduct what it calls a full and conclusive

Daubert inquiry before certification. Zurn further contends that the district court

applied the wrong standard and abused its discretion in certifying the warranty and

negligence classes and erred by including persons in the warranty class whose

plumbing systems had not yet leaked.

II.

Rule 23(c)(1)(A) provides that a district court should address class certification

at an "early practicable time after a person sues or is sued as a class representative."
-7-

When deciding whether common issues predominate over individual issues under

Rule 23(b)(3), the court should conduct a "rigorous analysis" including an

"examination of what the parties would be required to prove at trial." Avritt v.

Reliastar Life Ins. Co., 615 F.3d 1023, 1029 (8th Cir. 2010). Expert disputes

"concerning the factual setting of the case" should be resolved at the class certification

stage only to the extent "necessary to determine the nature of the evidence that would

be sufficient, if the plaintiff’s general allegations were true, to make out a prima facie

case for the class." Blades v. Monsanto Co., 400 F.3d 562, 567 (8th Cir. 2005). We

have never required a district court to decide conclusively at the class certification

stage what evidence will ultimately be admissible at trial. 

Here, both sides agree that the relevant expert testimony must be evaluated and

weighed by the court before it decides to certify a class. Zurn urges that we adopt a

new rule, requiring a district court to determine conclusively at an early stage, not just

whether or not expert evidence is sufficient to support class certification under Rule

23, but also whether that evidence will ultimately be admissible at trial. It urges us

to follow the approach used by a Seventh Circuit panel in American Honda Motor

Company, Inc. v. Allen, 600 F.3d 813, 816–17 (7th Cir. 2010) (per curiam). 

The plaintiffs in American Honda sought to certify a class of motorcycle

owners based on an alleged design defect affecting their motorcycles. The plaintiffs

relied on an expert who had created his own methodology and standards which he

then tested on a single used motorcycle. These tests had been developed only "to

assist with a lawsuit and [were] not conceived through the logical flow of independent

research," had a "sample size of one," and "lack[ed] acceptance" by the scientific

community. Id. at 816. The Seventh Circuit panel was thus dealing with a case with
4

It appears no other circuit has followed the approach advocated in American

Honda, and at least one court sitting en banc has rejected it. See Dukes v. Wal-Mart

Stores, Inc., 603 F.3d 571, 602 n.22 (9th Cir. 2010) (en banc), rev'd on other grounds,

564 U.S. —, 2011 WL 2437013 (Jun. 20, 2011). While an Eleventh Circuit panel

mentioned the case in a recent unpublished opinion, the issue in that case was the

weight afforded to certain expert testimony, not its admissibility. Sher v. Raytheon,

No. 09-15798, 2011 WL 814379 at *3 (11th Cir. Mar. 9, 2011) (unpublished).

-8-

expert conclusions based on flawed methodology and a sample size of one when it

stated its preference for an early full and conclusive Daubert review.4

The record in the case before us is very different from the one in American

Honda. No party in this case has alleged that the expert testimony here is similarly

flawed. Both sides agree that Dr. Staehle and Dr. Blischke are well qualified in their

respective fields and that they used generally recognized and reliable methodologies.

Zurn nonetheless contends that the district court should determine at the class

certification stage, and before merits discovery has even commenced, whether or not

the expert opinions will ultimately be admitted at trial.

Our own circuit precedent does not favor the approach urged by Zurn. In

Blades, we approved a district court decision which explicitly rejected a request for

a full Daubert inquiry at the class certification stage. 400 F.3d at 569. We affirmed,

concluding that the district court's "findings as to the experts' disputes were properly

limited to whether, if appellants' basic allegations were true, common evidence could

suffice, given the factual setting of the case, to show classwide injury." Id. at 575. 

In declining to conduct what Zu rn terms a full and conclusive Daubert inquiry, the

district court in Blades properly focused on "determin[ing] the nature of the evidence

that would be sufficient, if the plaintiff's general allegations were true, to make out a

prima facie case for the class." Id. at 567.
5

The dissent notes that the Supreme Court recently "doubt[ed]" a district court's

conclusion that "Daubert did not apply to expert testimony at the certification stage

of class-action proceedings." Wal-Mart v. Dukes, 2011 WL 2437013, at *8. The

district court here made no such conclusion. It rejected the homeowner contention

that it should consider all evidence that was "not fatally flawed" and proceeded to

apply Daubert by conducting a focused inquiry into expert reliability in light of the

available evidence.

-9-

In this case, the district court followed Blades by applying what it termed a

"tailored" Daubert analysis. Rejecting both parties' extreme positions, it examined the

reliability of the expert opinions in light of the available evidence and the purpose for

which they were offered.5

 We can hardly fault the trial court for following our

precedent in Blades, and we see no reason to abandon the "cardinal rule . . . that one

panel is bound by the decision of a prior panel." Owsley v. Luebbers, 281 F.3d 687,

690 (8th Cir. 2002). Moreover, we are not convinced that the approach of American

Honda would be the most workable in complex litigation or that it would serve case

management better than the one followed by the district court here. 

The district court sought to examine the reliability of the expert testimony in

light of the existing state of the evidence and with Rule 23's requirements in mind.

The record in this case illustrates why that approach was appropriate and why

requiring an even more conclusive Daubert inquiry at the class certification stage

would have been impractical. As the district court noted with respect to Dr. Blischke:

Dr. Blischke's analysis was circumscribed by the availability of warranty

claims data. However, as merits discovery unfolds and more information

becomes available, Dr. Blischke's 40 year estimate for the mean time to

failure may or may not be admissible.

It was after all Zurn which sought bifurcated discovery which resulted in a limited

record at the class certification stage, preventing the kind of full and conclusive

Daubert inquiry Zurn later requested. While there is little doubt that bifurcated

discovery may increase efficiency in a complex case such as this, it also means there
-10-

may be gaps in the available evidence. Expert opinions may have to adapt as such

gaps are filled by merits discovery, and the district court will be able to reexamine its

evidentiary rulings. See Walzer v. St. Joseph State Hosp., 231 F.3d 1108, 1113 (8th

Cir. 2000) ("Evidentiary rulings made by a trial court during motions in limine are

preliminary . . . ."). A court's rulings on class certification issues may also evolve.

See Fed. R. Civ. P. 23(c)(1)(C) ("An order that grants or denies class certification may

be altered or amended before final judgment."). 

Class certification "is inherently tentative," Coopers & Lybrand v. Livesay, 437

U.S. 463, 469 n.11 (1978), and may "require revisiting upon completion of full

discovery," Blades, 400 F.3d at 567. Zurn's desire for an exhaustive and conclusive

Daubert inquiry before the completion of merits discovery cannot be reconciled with

the inherently preliminary nature of pretrial evidentiary and class certification rulings.

The main purpose of Daubert exclusion is to protect juries from being swayed

by dubious scientific testimony. That interest is not implicated at the class certification

stage where the judge is the decision maker. The district court's "gatekeeping

function" under Daubert ensures that expert evidence "submitted to the jury" is

sufficiently relevant and reliable, Bonner v. ISP Technologies, Inc., 259 F.3d 924, 929

(8th Cir. 2001) (emphasis added), but "[t]here is less need for the gatekeeper to keep

the gate when the gatekeeper is keeping the gate only for himself," United States v.

Brown, 415 F.3d 1257, 1269 (11th Cir. 2005). Similar reasons support less stringent

application of Daubert in bench trials. See Charles Alan Wright, Victor James Gold,

29 Fed. Prac. & Proc. Evid. § 6266, n.90.2 (2010), and cases cited. The "usual

concerns of the [Daubert] rule— keeping unreliable expert testimony from the

jury—are not present in such a setting." Metavante Corp. v. Emigrant Sav. Bank, 619

F.3d 748, 760 (7th Cir. 2010).

Zurn correctly points out that we require district courts to rely only on

admissible evidence at the summary judgment stage, see Tuttle v. Lorillard Tobacco

Co., 377 F.3d 917, 924 (8th Cir. 2004), but the questions then are quite different than
-11-

at the class certification stage. Because summary judgment ends litigation without a

trial, the court must review the evidence in light of what would be admissible before

either the court or jury. See Fed. R. Civ. P. 56; Anderson v. Liberty Lobby, Inc., 477

U.S. 242, 248 (1986).

In contrast, a court’s inquiry on a motion for class certification is "tentative,"

"preliminary," and "limited." Coopers & Lybrand, 437 U.S. at 469 n.11; Blades, 400

F.3d at 566. The court must determine only if "questions of law or fact common to

class members predominate over any questions affecting only individual members

[and if] a class action is superior to other available methods for fairly and efficiently

adjudicating the controversy." Fed. R. Civ. P. 23(b)(3). As class certification

decisions are generally made before the close of merits discovery, the court's analysis

is necessarily prospective and subject to change, Blades, 400 F.3d at 567, and there

is bound to be some evidentiary uncertainty. Because a decision to certify a class is

far from a conclusive judgment on the merits of the case, it is "of necessity . . . not

accompanied by the traditional rules and procedure applicable to civil trials." Eisen

v. Carlisle & Jacquelin, 417 U.S. 156, 178 (1974).

We conclude that the district court did not err by conducting a focused Daubert

analysis which scrutinized the reliability of the expert testimony in light of the criteria

for class certification and the current state of the evidence. In doing so the district

court conducted the requisite "rigorous analysis" of the parties' claims to determine

"whether the defendant's liability to all plaintiffs may be established with common

evidence." Avritt, 615 F.3d at 1029. 

III.

After concluding its tailored Daubert analysis, the district court denied Zurn’s

motion to strike the opinions offered by Dr. Staehle and Dr. Blischke. On its appeal

Zurn does not dispute either of the expert’s qualifications or methodology. Their

reputations as eminent experts in their respective fields are not in question. Rather,
-12-

Zurn argues that their opinions were not based on "sufficient facts or data" and should

therefore have been stricken.

 Having already concluded that the district court applied the correct legal

standard in declining to strike the expert opinions, we will reverse those evidentiary

rulings only upon a showing that it abused its discretion in a way which "affected a

party's substantial rights." Weitz Co. v. MH Washington, 631 F.3d 510, 525 (8th Cir.

2011). We also keep in mind that, "[a]s a general rule, the factual basis of an expert

opinion goes to the credibility of the testimony, not the admissibility." Bonner, 259

F.3d at 929 (quoting Hose v. Chicago Nw. Transp. Co., 70 F.3d 968, 974 (8th Cir.

1996)). Such testimony should be excluded only if it "is so fundamentally

unsupported that it can offer no assistance to the jury." Id. at 929–30. 

According to Zurn, Dr. Staehle applied an unrealistic amount of strain in his

"U-bend" testing which affected his overall conclusion that its brass fittings invariably

would experience SCC. In the view of Zurn's expert, Dr. Staehle's decision to apply

a 20% strain in testing brass specimens was unreasonable because the actual strain on

properly installed brass fittings was lower. The homeowners respond that the 20%

strain was reasonable in the context of Dr. Staehle's experiments. Moreover, they

argue that any disagreement over the appropriate strain level only affects the weight

of the evidence, not its admissibility. 

The issue here is similar to one addressed in Quiet Technology DC-8, Inc. v.

Hurel-Dubois UK Ltd., 326 F.3d 1333, 1344 (11th Cir. 2003). There, an expert used

a reliable method (computational fluid dynamics), but the parties disputed whether the

expert "put the wrong information" into a computer program that he used to compute

his results. Id. at 1343–44. The circuit court determined that when parties dispute

"the specific numbers" to be used in an otherwise reliable scientific analysis, the

"alleged flaws . . . are of a character that impugn the accuracy of [the expert's] results,

not the general scientific reliability of his methods." Id. at 1345. The district court

had therefore not abused its discretion by declining to exclude the expert's evidence
-13-

under Daubert. Id. at 1346. Objections to generally reliable scientific evidence go to

its weight, not its admissibility. See id. at 1345–46, and cases cited.

The validity of one of Dr. Staehle's inputs was also challenged by Zurn. The

district court concluded that the question of the proper strain to be applied in the Ubend tests went to "the accuracy of Dr. Staehle's results, [but] not the general scientific

validity of his methods." As the Supreme Court pointed out in Daubert, when

evaluating an expert’s opinion, "[t]he focus . . . must be solely on principles and

methodology, not on the conclusions that they generate." 509 U.S. at 595. A district

court necessarily has "considerable discretion" in deciding whether to admit expert

testimony where the factual basis is disputed. Marvin Lumber & Cedar Co. v. PPG

Indus., Inc., 401 F.3d 901, 916 (8th Cir. 2005). We conclude that the district court did

not abuse its discretion in declining to strike Dr. Staehle's testimony.

Zurn's main attack on Dr. Blischke's testimony about system failure rates is that

he assumed a mean time to failure figure rather than attempting to calculate that figure

from available data. Dr. Blischke explained that it was necessary to assume a mean

time to failure figure because he lacked reliable warranty data from Zurn. He pointed

to Zurn's inadequate record keeping and evidence that many of its customers had

stopped reporting leaks after Zurn began to reject warranty claims. Zurn does not

directly dispute Dr. Blischke's position that it is generally acceptable to include a

reasonable assumption in a statistical analysis when there is insufficient data to

calculate a particular value. 

Because Dr. Blischke's assumed mean time to failure figure was not

unsupported, the district court did not abuse its discretion in declining to exclude his

opinion. Dr. Blischke testified that he adopted a 40 year mean time to failure figure

after examining a report in which Zurn itself referred to 40 years as "a normal

lifetime" for its fittings. He also stated that he relied on reports prepared by other

expert witnesses in this case. For example, in Dr. Staehle's expert opinion there was

"no evidence . . . that the Zurn fittings can perform reliably for 25 years . . . nor are
-14-

there any bases for a much longer design life of about 40 years." Dr. Blischke also

provided additional calculations based on longer mean time to failure figures, up to

100 years, and those figures still showed high failure rates within 25 years.

Zurn claims that there were other weaknesses in Dr. Blischke's approach. It

faults his assumptions that brass fittings would fail randomly and in different

households and that an average household would have 50 fittings. The record shows

that Dr. Blischke actually considered a range of variables in his analyses, just as he

did when considering mean time to failure figures. He provided failure rates, for

example, based on 40, 50, 60, and 100 fittings per household system. This approach

was reasonable, for Dr. Blischke's expertise is in statistics and reliability, not

plumbing or metallurgy. His testimony can help a fact finder understand the

implications of opinions offered by other experts such as Dr. Staehle. If a factfinder

doubts Dr. Blischke's assumptions, then the factfinder will discount his ultimate

conclusions or rely on his alternate calculations which account for different values.

Such possibilities do not diminish the validity of Dr. Blishcke's scientific methods.

An expert's opinions are not inadmissable simply because an underlying assumption

may be contestable. Marvin Lumber, 401 F.3d at 916.

The district court indicated that it was aware of certain limitations in Dr.

Blischke's analysis and that it had given his evidence its "proper weight." It also noted

that as additional evidence is uncovered during discovery, "Dr. Blischke's 40 year

estimate for the mean time to failure may or may not be admissible." There is nothing

in the record at this stage to show that Dr. Blischke's opinions are so "fundamentally

unsupported" as to require exclusion. See Bonner, 259 F.3d at 929–30. 

We conclude that the district court did not err or abuse its discretion in denying

Zurn's motion to strike the homeowners' expert testimony. 
-15-

IV.

Zurn argues that some members of the warranty class lacked standing to bring

their claims and that the district court therefore erred by certifying that class. We

ordinarily afford the district court "broad discretion in determining whether to certify

a class," Arthur Young & Co. v. Reves, 937 F.2d 1310, 1323 (8th Cir. 1991),

recognizing "the essentially factual basis of the certification inquiry and . . . the

district court's inherent power to manage and control pending litigation," Gene &

Gene LLC v. BioPay LLC, 541 F.3d 318, 325 (5th Cir. 2008). While we reverse only

for an abuse of that discretion, a district court "abuses its discretion if it commits an

error of law." Blades, 400 F.3d at 566.

A district court may not certify a class, however, "if it contains members who

lack standing." Avritt, 615 F.3d at 1034. If members "who lack the ability to bring

a suit themselves" are included in a class, the court lacks jurisdiction over their claims,

see id., and we therefore review Zurn's standing challenge de novo, see, e.g., Curtis

Lumber Co., Inc. v. Louisiana Pac. Corp., 618 F.3d 762, 770 (8th Cir. 2010). To show

standing, a plaintiff bears the burden of establishing "injury in fact . . . that is fairly

traceable to the challenged action of the defendant, and likely [to] be redressed by a

favorable decision." Braden v. Wal-Mart Stores, Inc., 588 F.3d 585, 591 (8th Cir.

2009). In most cases "the question whether [a plaintiff] has a cognizable injury

sufficient to confer standing is closely bound up with the question of whether and how

the law will grant him relief." Id.

In asserting a warranty claim, it "is not enough" for a plaintiff "to allege that

a product line contains a defect or that a product is at risk for manifesting this defect;

rather, the plaintiffs must allege that their product actually exhibited the alleged

defect." O'Neil v. Simplicity, Inc., 574 F.3d 501, 503 (8th Cir. 2009). In O'Neil, for

example, crib owners failed to state cognizable warranty claims because they had not

alleged that their cribs actually exhibited a dangerous defect that might have harmed
6

While Zurn refers to these class members as "no injury" plaintiffs, that label

presumes a negative answer to a contested question—whether or not these plaintiffs

have suffered a legally cognizable injury. This group is thus more appropriately

referred to as the "dry plaintiffs." 

-16-

their children; a mere likelihood that a crib might develop a dangerous defect was not

enough. Id. at 503–04.

Zurn argues that those plaintiffs whose plumbing systems have not leaked—a

group most accurately referred to as the "dry plaintiffs"6

—have no standing because

they, like the crib owners in O'Neil, have not suffered a cognizable injury. The

homeowners respond that the district court correctly determined that the dry plaintiffs

have alleged a current harm because they allege that the Zurn brass fitting contained

a defect upon installation in breach of Minnesota warranty law. See Minn. Stat. §§

336.2-313 & 2-314.

Pointing to several words in the class certification order, Zurn argues that the

district court did not follow our rule that a manifestation of a defect is required for a

warranty claim. See O'Neil, 574 F.3d at 503. At one point the district court

commented that the homeowners were "not required to allege and prove a

manifestation of [a] defect." It had however stated in its previous sentence that the

homeowners had to "prove that the brass fittings are defective" in order to recover in

warranty. When the sentences are read together, it is clear that the court’s position

was that to give rise to a warranty claim a fitting must contain a defect, but that it need

not have already caused external damage. This position was consistent with O'Neil

even if there was some lack of precision in the district court's statement of the

applicable standard. O’Neil never indicated that a child would have to be injured by

a crib for a defect to be manifest. 

The dry plaintiff claims are distinct from any brought by hypothetical "no injury

plaintiffs," because the dry plaintiffs had alleged that their brass fittings exhibited a
-17-

defect. In contrast to the plaintiffs in O'Neil, the homeowners do not argue that the

fittings merely "risk" developing SCC. They allege that SCC afflicts all of the fittings

upon use, regardless of water conditions or installation practices. As they have put it,

SCC "is already manifest in all systems." They supported this contention with expert

testimony. Dr. Staehle opined, for example, that SCC develops in "Zurn fittings . . .

as soon as they are exposed to domestic water." Given this evidence, the district court

did not err in determining that the dry plaintiffs were not "no injury" parties simply

because their plumbing systems had not yet leaked. 

We conclude that the district court did not err in concluding that the claims of

the dry plaintiffs are cognizable under Minnesota warranty law and that they may seek

damages if they succeed in proving their claim of a universal inherent defect in breach

of warranty. See Minn. Stat. § 336.2-714; Peterson v. Bendix Home Sys., Inc., 318

N.W. 2d 50, 53 (Minn. 1982) (explaining damages available for breach of warranty

under the Minnesota UCC). The dry plaintiffs therefore had standing to bring their

claims, and the district court did not err in certifying a class which included them.

Zurn further contends that the district court abused its discretion in granting

class certification to the dry plaintiff claims before interpreting the terms of the

company's limited warranty. It argues that its warranty bars a claim unless a fitting

has already leaked. In support Zurn cites its own statement disclaiming implied

warranties along with the following sentence: "Under this warranty, you only have

a right to reimbursement if the alleged failure or leak is determined to be a direct result

of the product(s) as covered in this warranty and occurred during the warranty period"

(emphasis added). The homeowners respond that SCC is a failure covered by the

warranty.

The interpretation of Zurn's warranty and its application to all of the dry

plaintiffs is a common question that lends itself to efficient class wide resolution

under Rule 23. Pella Corp. v. Saltzman, 606 F.3d 391, 394 (7th Cir. 2010); see also

Wolin v. Jaguar Land Rover N. Am., LLC, 617 F.3d 1168, 1173–74 (9th Cir. 2010);
-18-

Daffin v. Ford Motor Co., 458 F.3d 549, 553–54 (6th Cir. 2006). While disputes about

Rule 23 criteria may overlap with questions going to the merits of the case, the district

court should not resolve the merits of the case at class certification. Blades, 400 F.3d

at 567. If, at a later date, the court were to conclude that the dry plaintiff claims are

indeed barred by Zurn's limited warranty, it may decertify the class or amend the class

definition, see Fed R. Civ. P. 23(c)(1)(C); Daffin, 458 F.3d at 554, or grant summary

judgment to Zurn on such claims under Rule 56. For these reasons we find no abuse

of discretion in the district court’s decision to certify a warranty class including these

plaintiffs.

V.

Zurn also argues that the district court erred by certifying the warranty and

negligence classes because their common questions do not predominate over

individual questions. See Fed. R. Civ. P. 23(b)(3). We review the district court's

rulings on issues of law de novo and its application of the law for an abuse of

discretion. Blades, 400 F.3d at 566.

Rule 23(b)(3)'s requirement that common issues of fact or law must

predominate over individual questions "tests whether proposed class members are

sufficiently cohesive to warrant adjudication by representation." Amchem Prods., Inc.

v. Windsor, 521 U.S. 591, 623 (1997). Individual issues are those which require

"evidence that varies from member to member" to make a prima facie showing.

Blades, 400 F.3d at 566. Common questions are those for which a prima facie case

can be established through common evidence. Id. When determining "whether

common questions predominate, a court must conduct a limited preliminary inquiry,

looking behind the pleadings," but that inquiry should be limited to determining

whether, if the plaintiffs' "general allegations are true, common evidence could suffice

to make out a prima facie case for the class." Id. While limited in scope, this analysis

should also be "rigorous." Avritt, 615 F.3d at 1029.
-19-

Zurn complains about the district court's mention of taking "the substantive

allegations in the plaintiff's complaint as true" while considering a motion for class

certification. Zurn contends that this premise "permeates all of the district court's

findings and conclusions" and cannot be reconciled with the requirement that it

conduct a "rigorous inquiry" into whether liability "may be established with common

evidence." See Avritt, 615 F.3d at 1029. The homeowners respond first by pointing

out that the district court recognized the requirement for it to conduct a rigorous

analysis in the same paragraph containing the language criticized by Zurn. The court

clearly stated that it would granted class certification "[o]nly after a rigorous analysis

of the proposed class and the requirements of Rule 23," citing General Telephone Co.

of the Southwest v. Falcon, 457 U.S. 147, 161 (1982). The homeowners further

emphasize that the rigor of the court's analysis is shown by the facts that it rejected

certification as to some of their claims and modified the scope of the class as to others.

Our review of the record and the district court's certification order indicates that

it conducted a rigorous inquiry to decide whether "common evidence could suffice to

make out a prima facie case for the class." Blades, 400 F.3d at 566. The court did not

simply take as true all of the homeowner allegations. In addition to scrutinizing the

testimony of the parties' expert witnesses, the court carefully examined the

homeowner claims along with Zurn's defenses. In considering the homeowner

request for class certification of their consumer protection claims, for example, it

weighed and rejected their contention that they could prove by common evidence that

all consumers "failed to receive the same material omission" of information "essential

in making the decision to purchase" Zurn's product. 

A comparison of the consumer protection claims with the warranty and

negligence claims is instructive. As we explained in In re St. Jude Medical, Inc., 522

F.3d 836, 838 (8th Cir. 2008), "[i]n a typical common-law fraud case, a plaintiff must

show that he or she received the defendant's alleged misrepresentation and relied on

it." Claims requiring individual proof of reliance are generally not amenable to class

certification because common evidence could not "suffice to make out a prima facie
7

The allegation that all of Zurn's brass fittings suffer from a universal defect

along with the expert testimony which supports it differentiates this case from that

recently considered by the Supreme Court in Wal-Mart v. Dukes. There, the plaintiffs

sought certification of a nationwide class of over a million women who allegedly

suffered sex discrimination by Wal-Mart. The Court concluded that the plaintiffs had

not presented any "significant proof" that Wal-Mart had a "general policy of

discrimination" which might have satisfied Rule 23(a)(2)'s commonality requirement.

2011 WL 2437013, at *8. Here, in contrast, the evidence of a universal defect raises

a critical question common to all members of the classes certified by the district court.

-20-

case for the class." See Blades, 400 F.3d at 566. In the case of warranty and

negligence claims premised on a universal and inherent product defect, however,

plaintiffs may rely on common evidence to establish a prima facie case because there

is no similar individual reliance requirement for such claims.7

 See Minn. Stat. §

336.2-313, cmt. 3; Lubbers v. Anderson, 539 N.W. 2d 398, 401 (Minn. 1995)

(elements of a negligence claim); Peterson, 318 N.W. 2d at 52–53 (elements of a

warranty claim).

While the existence of individual defenses may be important in a court's

decision to certify a class, see St. Jude, 522 F.3d at 840, the relevance of such defenses

must be subjected to the same rigorous inquiry as plaintiffs' claims. The district court

examined Zurn's assertion that individual water conditions or faulty installation might

have caused the alleged failures as opposed to a universal product defect. The court

also considered the plaintiffs' argument that there was not sufficient evidence showing

that individual conditions or installation differences may have caused SCC in Zurn's

brass fittings. 

With respect to the warranty claims the district court concluded that given the

homeowner claim of a universal defect, the question of "proximate cause will not

involve predominately individual determinations, and resolution of that issue would

be common to the class." Similarly, with respect to the negligence claims the court

determined that "[t]he question of liability does not require the specific individually
8

The dissent indicates that it doubts whether the district court conducted a

sufficiently "rigorous analysis" of the class certification questions presented. We note

that the experienced trial judge in this case issued a 31 page order, examining the

evidence produced with respect to each Rule 23 requirement for the three proposed

classes. The time restraints faced by busy trial courts make it unrealistic to expect

exhaustive and polished opinions on all the legal issues before them.

-21-

tailored examinations proposed by Zurn." The district court stated that it was

"convinced that the Plaintiffs have adduced sufficient evidence to support their theory

of the case" in respect to the warranty and negligence claims. 

The question at class certification is not whether the plaintiffs have already

proven their claims through common evidence. Rather, it is whether questions of law

or fact capable of resolution through common evidence predominate over individual

questions. Blades, 400 F.3d at 566–67. In light of the record and the district court's

predominance analysis, we discern no abuse of discretion in its decision to grant class

certification as to the warranty and negligence classes.8

 Merits discovery remains to

be undertaken in the district court and as it continues, the bases for the district court's

necessarily prospective rulings may change. The rules of civil procedure allow for

flexibility if such changes are needed.

VI.

After thoroughly reviewing the record made in the district court in light of the

controlling law, we conclude that the district court did not commit legal error or abuse

its discretion. Accordingly, its class certification order is affirmed.

GRUENDER, Circuit Judge, dissenting.

Because I conclude that the district court abused its discretion when it certified

the breach of warranty class and the negligence class, I respectfully dissent.
-22-

I. DISCUSSION

A. Breach of Warranty Class—Standing

The court holds that those plaintiffs in the warranty class who own Zurn fittings

that have not failed or leaked—the so-called “dry plaintiffs”—have suffered an injury

and have stated “cognizable [claims] under Minnesota warranty law.” Ante at 17. To

reach this conclusion, the court improperly characterizes our precedent and overlooks

the axiom that “liability does not exist in a vacuum; there must be a showing of some

damage.” Briehl v. Gen. Motors Corp., 172 F.3d 623, 628 (8th Cir. 1999) (quoting

Feinstein v. Firestone Tire & Rubber Co., 535 F. Supp. 595, 602 (S.D.N.Y. 1982)).

“On every writ of error or appeal, the first and fundamental question is that of

jurisdiction.” Great So. Fire Proof Hotel Co. v. Jones, 177 U.S. 449, 453 (1900).

Failure to establish standing deprives this court of jurisdiction to hear the suit. Steel

Co. v. Citizens for a Better Env’t, 523 U.S. 83, 103 (1998). The “core component of

standing is an essential and unchanging part of the case-or-controversy requirement

of Article III.” Lujan v. Defenders of Wildlife, 504 U.S. 555, 560 (1992). The dry

plaintiffs, as the party invoking federal jurisdiction, bear the burden of establishing

that they have standing. See id. at 561. As such, a class may only “‘be defined in

such a way that anyone within it would have standing[,]’ and . . . a named plaintiff

cannot represent a class of persons who lack the ability to bring suit themselves.”

Avritt v. Reliastar Life Ins. Co., 615 F.3d 1023, 1034 (8th Cir. 2010) (quoting Denney

v. Deutsche Bank AG, 443 F.3d 253, 264 (2d Cir. 2006)). 

The party asserting standing must demonstrate that he “has suffered an ‘injury

in fact’—an invasion of a legally protected interest which is (a) concrete and

particularized, and (b) actual or imminent, not conjectural or hypothetical.”

Republican Party of Minn. v. Klobuchar, 381 F.3d 785, 791-92 (8th Cir. 2004)

(quoting Lujan, 504 U.S. at 560). As the court today notes, “the question whether [a

plaintiff] has a cognizable injury sufficient to confer standing is closely bound up with
-23-

the question of whether and how the law will grant him relief.” Braden v. Wal-Mart

Stores, Inc., 588 F.3d 585, 591 (8th Cir. 2009); see also Warth v. Seldin, 422 U.S.

490, 500 (1975) (stating that the inquiry into whether the party asserting standing has

shown an injury in fact “often turns on the nature and source of the claim asserted”).

We review a district court’s determination that a party has standing de novo.

Constitution Party of S.D. v. Nelson, 639 F.3d 417, 420 (8th Cir. 2011).

“Courts have been particularly vigilant in requiring allegations of injury or

damages in products liability cases.” Briehl, 172 F.3d at 627. Central to the analysis

is an allegation of not only an alleged defect, but also the manifestation of that defect.

At this critical juncture in the analysis, the district court veered off course and applied

the wrong legal standard: “Plaintiffs need only allege and prove that the brass fittings

are defective and do not conform to the warranty. They are not required to allege and

prove a manifestation of that defect.” In re Zurn Pex Plumbing Prods. Liab. Litig.,

267 F.R.D. 544, 564 (D. Minn. 2010). Such a statement is without support in our

circuit. In fact, “[i]t is well established that purchasers of an allegedly defective

product have no legally recognizable claim where the alleged defect has not

manifested itself in the product they own.” Briehl, 172 F.3d at 628 (quoting Weaver

v. Chrysler Corp., 172 F.R.D. 96, 99 (S.D.N.Y. 1997)). 

Although the court today applies the proper legal standard, it nonetheless holds

that the dry plaintiffs have alleged a cognizable injury. In doing so, the court

misapplies our decision in O’Neil v. Simplicity, Inc., 574 F.3d 501 (8th Cir. 2009). In

that case, John and Jill O’Neil purchased a crib that featured a drop-side

mechanism—a mechanism allowing one side of the crib to be lowered, “making it

easier to place a child into and remove it from the crib.” Id. at 502. Four years after

the O’Neils purchased the crib, the Consumer Product Safety Commission and the

manufacturer “announced a voluntary recall of about one million cribs . . . prompted

by a hardware defect that made it possible for the drop-side to detach from the crib,

creating a dangerous gap in which a child could get caught.” Id. The O’Neils sued

the manufacturer for, inter alia, breach of express and implied warranties. Id. at 503.
-24-

The plaintiffs purported to represent a class of all persons in Minnesota who had

purchased a crib, excluding any individuals who suffered a personal injury as a result

of the allegedly defective crib. 

In their brief to our court, the O’Neils argued that “Plaintiffs’ crib contains a

serious hardware defect that allows the drop side to separate from the crib frame. This

hardware defect creates a gap that allows an infant or child to be trapped between the

drop side and the crib frame. The defect is present in over 1 million of Defendants’

cribs . . . .” In their reply brief, the O’Neils stressed that “each and every Graco crib

has ‘older-style hardware’ that causes the drop side to detach from the crib frame and

creates an entrapment gap that injures infants and small children. The Graco crib

model that the Plaintiffs purchased for their grandchildren to sleep has this defect”

(emphasis in original). Thus, the O’Neils argued, “Plaintiffs have pleaded the existed

[sic] of a specific defect that has exhibited or ‘manifested’ itself in the Graco crib that

the Plaintiffs own.”

Our court was not persuaded. Even though the O’Neils alleged that their crib

contained a defect that had manifested itself in the drop-side hardware, the court held

that the O’Neils had failed to state a cognizable warranty claim because they had not

alleged that “a separation [of the drop-side] ha[d] ever occurred in their crib.” O’Neil,

574 F.3d at 503. For a claim to succeed, we held that “plaintiffs must allege that their

product actually exhibited the alleged defect.” Id. As such, where “a product

performs satisfactorily and never exhibits an alleged defect, no cause of action lies.”

Id. at 504 (quoting Briehl, 172 F.3d at 628). The O’Neils’ claim failed because, while

they alleged that the hardware defect was manifest in their crib, they did not allege

that the defect resulted in the separation of the drop-side from the crib. In essence, we

held in O’Neil that simply owning a product with an alleged defect does not give rise

to a warranty claim until that defect causes the product to perform unsatisfactorily.

Id. (finding that “the O’Neils’ crib has not exhibited the alleged defect” even though

the O’Neils alleged that a defect had manifested). 
-25-

Just as the O’Neils alleged that the defect had “manifested” simply by the

existence of the hardware in their crib, the dry plaintiffs here argue that “the chemical

and physical process of [stress corrosion] cracking[] is already manifest in all

systems.” Likewise, just as the O’Neils failed to allege that the hardware defect

resulted in the drop side separating from their crib, the dry plaintiffs fail to allege that

the process of stress corrosion cracking has caused leaks in their Zurn fittings. See id.

at 505 (“The O’Neils’ crib performs just as it was intended, and thus there is no injury

and no basis for relief.”). 

The court today misconstrues our decision in O’Neil in at least two ways. First,

the court attempts to distinguish that decision by stating that the O’Neils “had not

alleged that their cribs actually exhibited a dangerous defect that might have harmed

their children” but instead only had alleged “a mere likelihood that a crib might

develop a dangerous defect.” Ante at 16. To the contrary, the O’Neils did not allege

merely that their crib was at risk of developing a hardware defect; they expressly

alleged that “each and every Graco crib” had defective hardware—a defect that might

have harmed their children. We held that such allegations were insufficient because

the hardware defect had not manifested itself: the drop-side had not separated from

the crib and the crib continued to perform as intended. Second, the court attacks a

straw man, stating that “O’Neil never indicated that a child would have to be injured

by a crib for a defect to be manifest.” Ante at 16. While true, this distinction sheds

no light on the inquiry. If the O’Neils had alleged merely that their drop side had

separated from their crib—with no accompanying allegation of injury to a child—the

alleged defect in the crib’s hardware would have manifested, the crib no longer would

have functioned as intended, and the O’Neils would have had a cognizable claim. By

analogy, if the dry plaintiffs had alleged that their Zurn fittings exhibited leaks, the

alleged defect would be manifested, the plumbing products would no longer have

functioned as intended, and the dry plaintiffs would have a cognizable claim. But the

dry plaintiffs have not alleged this—and thus they have not alleged a sufficient injury

to establish standing. 
-26-

Like the O’Neils, the dry plaintiffs attempt to circumvent this problem by

alleging that they have suffered an economic injury. According to the O’Neils’ brief,

they sought “the benefit of their bargain with Defendants, or the difference in the

value of the crib they were promised, namely a fully functioning drop side crib . . . and

what they received, a crib containing a hardware defect that makes the crib an unsafe

environment for children and prevents the drop side from functioning as represented.”

According to the dry plaintiffs in the instant case, their economic injury includes “the

decreased value—because of the inherent defects—of the plumbing itself” and “the

cost of replacing systems.” Further, the dry plaintiffs argue that the Zurn products

they received—fittings subject to the process of stress corrosion cracking—do not

conform with the products which they were promised—fittings that would “outlast the

life of a home.” We rejected the “benefit of the bargain” argument in O’Neil: “[t]he

problem with this argument is that, because the O’Neils’ crib has not exhibited the

alleged defect, they have necessarily received the benefit of their bargain. The

O’Neils purchased a crib with a functioning drop-side and that crib continues to have

a functioning drop-side.” O’Neil, 574 F.3d at 504. In other words, even though the

O’Neils alleged that their crib exhibited defective hardware, they received the benefit

of the bargain because the alleged defect had not resulted in the crib not performing

as it was intended. Likewise, the dry plaintiffs purchased Zurn fittings that have

functioned as intended from the date of purchase to the date they filed this litigation.

Therefore, they too have received the benefit of the bargain.

The Fifth Circuit reached a similar conclusion in Rivera v. Wyeth-Ayerst Labs.,

283 F.3d 315 (5th Cir. 2002). In that case, Elizabeth Rivera purchased and ingested

Duract, a Wyeth-manufactured painkiller. Soon after receiving complaints of liver

failure from patients taking the drug, Wyeth removed Duract from the market. Rivera,

for whom Duract functioned as intended and did not cause liver problems, sought to

represent a class of “all patients who were prescribed, had purchased, and had ingested

Duract but suffered no physical or emotional injury.” Id. at 317. Rivera argued that

she had suffered a concrete economic injury in that she had not received the benefit

of the bargain because she purchased a defective drug that was thought to be much
9

 Allowing plaintiffs who own properly functioning Zurn fittings to sue under

the benefit of the bargain theory is not only economically inefficient but also could

result in double recovery. See In re Bridgestone/Firestone, Inc. Tires Prods. Liab.

Litig., 288 F.3d 1012, 1017 (7th Cir. 2002) (“Plaintiffs describe the injury as financial

rather than physical and seek to move the suit out of the tort domain and into that of

contract (the vehicle was not the flawless one described and thus is not merchantable,

a warranty theory) . . . . It is not clear that this maneuver actually moves the locus

from tort to contract. If tort law fully compensates those who are physically injured,

then any recoveries by those whose products function properly mean excess

compensation.”). In Bridgestone/Firestone, Judge Easterbrook provided an apt

illustration of why a mixed system of recovery in both contract and tort leads to

inefficient outcomes: 

Consider an example. Defendant sells 1,000 widgets for $10,000 apiece.

 If 1% of the widgets fail as the result of an avoidable defect, and each

injury creates a loss of $50,000, then the group will experience 10

failures, and the injured buyers will be entitled to $500,000 in tort

damages. That is full compensation for the entire loss; a manufacturer

should not spend more than $500,000 to make the widgets safer.

Suppose, however, that uninjured buyers could collect damages on the

theory that the risk of failure made each widget less valuable; had they

known of the risk of injury, these buyers contend, they would have paid

-27-

safer than it was. Had patients known of Duract’s risks to the liver, Rivera claimed

she would have been able to purchase Duract for a lower price, presuming that riskier

drugs command a lower market price. A panel of the Fifth Circuit unanimously

disagreed and held that Rivera, and the members of the putative class, lacked standing

because they had not alleged a concrete and particularized injury to a legally protected

interest: “Rivera paid for an effective pain killer, and she received just that—the

benefit of her bargain.” Id. at 320. “Duract worked. Had Wyeth provided additional

warnings or made Duract safer, the plaintiffs would be in the same position they

occupy now.” Id. 

Just as the plaintiffs in Rivera and O’Neil received the benefit of their bargain,

so too did the dry plaintiffs in this case. The dry plaintiffs bargained for, and now

own, Zurn fittings that function exactly as intended.9

 See id.; cf. In re Canon
only $9,500 per widget—for the expected per-widget cost of injury is

$500, and each buyer could have used the difference in price to purchase

insurance (or to self-insure, bearing the risk in exchange for the lower

price). On this theory the 990 uninjured buyers would collect a total of

$495,000. The manufacturer’s full outlay of $995,000 ($500,000 to the

10 injured buyers + $495,000 to the 990 uninjured buyers) would be

nearly double the total loss created by the product’s defect. This would

both overcompensate buyers as a class and induce manufacturers to

spend inefficiently much to reduce the risks of defects. A consistent

system—$500 in damages to every buyer, or $50,000 in damages to

every injured buyer—creates both the right compensation and the right

incentives. A mixed system overcompensates buyers and leads to excess

precautions.

Id. at 1017 n.1 (internal citations omitted). 

-28-

Cameras Litig., 237 F.R.D. 357, 360 (S.D.N.Y. 2006) (“A plaintiff who purchases a

digital camera that never malfunctions over its ordinary period of use cannot be said

to have received less than what he bargained for when he made the purchase.”). 

I would conclude that, until the defect they allege manifests so that their Zurn

fittings no longer perform as intended, the dry plaintiffs have suffered no injury in

fact—economic or otherwise—and, therefore, lack standing. See O’Neil, 574 F.3d at

505; Rivera, 283 F.3d at 320; Briehl, 172 F.3d at 628-29.

B. Breach of Warranty Class—Predominance

Questions of law and fact common to the remaining members of the breach of

warranty class—those members whose Zurn plumbing products exhibit leaks and no

longer perform as intended—do not predominate over questions affecting individual

members. Thus, I would conclude that the putative breach of warranty class fails to

meet the predominance requirement of Fed. R. Civ. P. 23(b)(3). 

“A court may certify a class under Rule 23(b)(3) only if it finds that . . . the

questions of law or fact common to the members of the class predominate over any
-29-

questions affecting only individual members, and that a class action is superior to

other available methods for the fair and efficient adjudication of the controversy.”

Szabo v. Bridgeport Machs., Inc., 249 F.3d 672, 676 (7th Cir. 2001) (citing Fed. R.

Civ. P. 23(b)(3)); see also Avritt, 615 F.3d at 1029. “In making its [predominance]

determination, the district court must undertake a ‘rigorous analysis’ that includes

examination of what the parties would be required to prove at trial.” Avritt, 615 F.3d

at 1029 (citing Elizabeth M. v. Montenez, 458 F.3d 779, 786 (8th Cir. 2006)). “The

court may also be called upon to ‘resolve disputes concerning the factual setting of the

case.’” Id. (quoting Blades v. Monsanto Co., 400 F.3d 562, 575 (8th Cir. 2005)).

Such a rigorous analysis is even more appropriate in light of the amendments

made to Rule 23 in 2003. “First, the amended rule removes from prior Rule

23(c)(1)(C) the provision that class certification ‘may be conditional.’ Second, the

amended rule replaces the provision of prior Rule 23(c)(1)(A) that a class certification

decision be made ‘as soon as practicable’ with a provision requiring the decision ‘at

an early practicable time.’” Miles v. Merrill Lynch & Co., (In re Initial Pub. Offering

Sec. Litig.), 471 F.3d 24, 39 (2d Cir. 2006). Moreover, “the Advisory Committee

states that ‘[a] court that is not satisfied that the requirements of Rule 23 have been

met should refuse certification until they have been met.’” Id. (alteration in original)

(citing Fed. R. Civ. P. 23(c)(1)(C) Adv. Comm. Notes 2003).

Before it determined that the breach of warranty class met the predominance

requirement, the district court conceded that, “[b]ecause Zurn’s warranty specifically

excludes failures due to improper installation and corrosive water quality, individual

questions of proximate cause may exist as to class members whose Zurn[] brass crimp

fittings have already failed and who have suffered resulting property damage.” In re

Zurn Pex Plumbing, 267 F.R.D. at 563. The district court concluded, however, that

because the vast majority of the class had “not suffered property damage and seek

only replacement of a nonconforming product,” proximate cause issues would not

predominate. Id.
10 While the court in Blades employed this language, Blades, 400 F.3d at 566,

it went on to require that a district court conduct a rigorous analysis that “may require

the court to resolve disputes going to the factual setting of the case, and such disputes

may overlap the merits of the case,” id. at 567. Since our decision in Blades, our court

has continued to emphasize that district courts must “undertake a ‘rigorous analysis’

that includes examination of what the parties would be required to prove at trial.”

Avritt, 615 F.3d at 1029 (quoting Elizabeth M., 458 F.3d at 786). Engaging in such

a rigorous analysis comports with my view that “[t]he proposition that a district judge

must accept all of the complaint’s allegations when deciding whether to certify a class

cannot be found in Rule 23 and has nothing to recommend it.” Szabo, 249 F.3d at

675; accord In re Hydrogen Peroxide Antitrust Litig., 552 F.3d 305, 318 (3d Cir.

-30-

Because I would hold that the dry plaintiffs lack standing, the only remaining

members of the putative breach of warranty class are those whose fittings already have

leaked. For these remaining plaintiffs, individual questions of causation predominate

over common questions. To establish a warranty claim in Minnesota, a plaintiff must

prove (1) the existence of a warranty, (2) a breach of that warranty, and (3) a causal

link between the breach and the alleged harm. See Peterson v. Bendix Home Sys., Inc.,

318 N.W.2d 50, 52-53 (Minn. 1982). The Zurn express warranty excludes failures or

leaks caused by, inter alia, “damage due to tear, breaks or other external damages

before, during, or after installation,” “exposure to harmful, unauthorized, or

unanticipated chemicals or substances or corrosive water conditions,” and “damage

or wear from abnormal operating conditions, accident, abuse, misuse, or unauthorized

alterations or repair.” Zurn’s expert opined that those plaintiffs who relied on well

water or used water softeners subjected their fittings to an extremely corrosive

environment. As such, for the plaintiffs to prove that their Zurn fittings failed because

of stress corrosion cracking and not because of any one of the number of reasons

excluded from warranty coverage, the district court will be forced to engage in

individual factual inquiries regarding the installation and operating conditions of each

homeowner’s Zurn plumbing products. Even if all Zurn fittings eventually will fail

from stress corrosion cracking, another factor, like improper installation, abnormal

operation, or exposure to corrosive water conditions, still may have caused the failure

and property damage experienced by these plaintiffs. In other words, even “if the

plaintiff[s’] general allegations are true,”10 Blades, 400 F.3d at 566, common evidence
2008); Brown v. Am. Honda (In re New Motor Vehicles Can. Export Antitrust Litig.),

522 F.3d 6, 26 (1st Cir. 2008); Miles, 471 F.3d at 33, 41-42; Unger v. Amedisys Inc.,

401 F.3d 316, 321-22 (5th Cir. 2005); Gariety v. Grant Thornton, LLP, 368 F.3d 356,

366 (4th Cir. 2004). 

-31-

would be insufficient for these plaintiffs to prove their breach of warranty claim.

Therefore, I would conclude that the district court abused its discretion by certifying

the breach of warranty class.

C. Negligence Class—Predominance 

Similar individual issues of causation predominate over common issues for

those plaintiffs in the negligence class. The district court found that “[a] fact question

does exist as to whether the failures are due to a single cause or multiple causes. If

Plaintiffs can prove that the crimp fittings suffer from a uniform, inherent design and

manufacturing defect, and that the defect is the only cause of failure in the majority

of the cases, then proximate cause will not involve predominantly individual

determinations.” In re Zurn Pex Plumbing, 267 F.R.D. at 565. This conclusion is

problematic. As an initial matter, the district court’s reasoning is circular: essentially,

according the district court, if the plaintiffs can prove proximate causation through

common evidence, “then proximate cause will not involve predominantly individual

determinations.” See id. This conclusion is merely a restatement of the predominance

inquiry. 

More importantly, to show that stress corrosion cracking was the proximate

cause of the failure, each plaintiff will need to prove that his property damage was

caused by an inherent defect in Zurn’s fittings—and, alternatively, not caused by

corrosive water conditions, improper installation, improper use, abnormal operating

conditions, or another factor. As such, this inquiry will be inherently individual in

nature and not conducive to class-wide resolution. Moreover, Zurn has presented

expert testimony that stress corrosion cracking occurs only when its fittings are

subjected to unusual stress and a corrosive environment. The district court did not
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undertake a “rigorous analysis” regarding the contradictory testimony of the parties’

experts to determine whether stress corrosion cracking requires a corrosive

environment or whether stress corrosion cracking occurs in any water within the

lifetime of the fittings. Without resolving this question, I see no way to determine

whether common proof is sufficient for the plaintiffs’ case to succeed. While this

inquiry bleeds into the merits, it is necessary to determine the factual setting of the

case. “A district judge may not duck hard questions by observing that each side has

some support, or that considerations relevant to class certification also may affect the

decision on the merits. Tough questions must be faced and squarely decided, if

necessary by holding evidentiary hearings and choosing between competing

perspectives.” West v. Prudential Sec., Inc., 282 F.3d 935, 938 (7th Cir. 2002).

Therefore, because individual issues of causation predominate over common issues,

I conclude that the district court also abused its discretion by certifying the negligence

class.

D. Daubert and Class Certification

While I would not have reached the question of whether the district court

should have conducted a full inquiry into the admissibility of the plaintiffs’ experts’

testimony under Daubert v. Merrill Dow Pharmaceuticals, Inc., 509 U.S. 579 (1993),

I disagree with the court’s discussion and analysis of this issue. 

First, the court errs by characterizing our decision in Blades as controlling this

question, see ante at 9, because Blades did not address it. In Blades, the defendants

asked the district court to conduct a full Daubert inquiry into the admissibility of the

testimony of the plaintiffs’ key expert. The district court refused to address

admissibility under Daubert, stating that “I believe it is appropriate for me to consider

all evidence at this stage of the proceedings.” Blades, 400 F.3d at 569 (quoting the

district court). After the district court considered the plaintiffs’ expert evidence, it

ruled in favor of the defendants, determining that the “[expert] testimony does not

show that impact can be demonstrated on a class-wide basis.” Id. (quoting the district
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court). We affirmed and held that, “in ruling on class certification, a court may be

required to resolve disputes concerning the factual setting of the case. This extends

to the resolution of expert disputes concerning the import of evidence concerning the

factual setting . . . .” Id. at 575. “[W]e believe the district court’s findings as to the

experts’ disputes were properly limited to whether, if appellants’ basic allegations

were true, common evidence could suffice, given the factual setting of the case, to

show classwide injury.” Id. (emphasis added).

Thus, our decision in Blades addressed the scope of the district court’s fact

finding with respect to conflicting expert testimony, not whether the testimony should

have been admitted in the first place. Because the defendants in Blades prevailed in

the district court and, therefore, did not appeal the district court’s refusal to conduct

a full Daubert analysis, the court in Blades simply was not presented with and did not

decide the question of the admissibility of the proffered expert evidence under

Daubert. As such, the question of the appropriate scope of a district court’s Daubert

inquiry at the class certification stage was not decided by the court in Blades and has

remained an open question until the court’s decision today. 

To resolve this open question, I note first that the Supreme Court has expressed

disapproval of the position taken by the court today. See Wal-Mart Stores, Inc. v.

Dukes, 564 U.S. ---, 2011 WL 2437013, at *8 (U.S. Jun. 20, 2011) (“The District

Court concluded that Daubert did not apply to expert testimony at the certification

stage of class-action proceedings. We doubt that is so . . . .” (internal citation

omitted)). “The statement, to be sure, is dictum, . . . but inferior courts can take their

cues from the Supreme Court’s dicta.” Scheduled Skyways, Inc. v. Nat’l Mediation

Bd., 738 F.2d 339, 342 (8th Cir. 1984). Second, I find appropriate the standard

expounded by two of our sister circuits. In American Honda Motor Co. v. Allen, 600

F.3d 813 (7th Cir. 2010) (per curiam), the district court certified a class of Honda

motorcycle purchasers who alleged that the front steering assembly of their GL 1800

motorcycles “wobble[d],” or shook excessively. Id. at 814. Plaintiffs’ expert stated

that any wobble or oscillation of the steering assembly should dissipate within one
-34-

second so as to prevent riders from reacting to it. Based on the test of one GL 1800

motorcycle, the expert concluded that all GL 1800 motorcycles failed the standard he

had devised and, thus, were defective. Honda argued that the expert’s opinions failed

the reliability standards established by Daubert. While the district court expressed

reservations about the reliability of the opinions, the court declined to strike the

expert’s report “at this early stage of the proceedings,” id. at 815 (quoting the district

court), and granted plaintiffs’ motion for class certification.

The Seventh Circuit reversed and held that, “when an expert’s report or

testimony is critical to class certification, as it is here[,] . . . a district court must

conclusively rule on any challenge to the expert’s qualifications or submissions prior

to ruling on a class certification motion. That is, the district court must perform a full

Daubert analysis before certifying the class if the situation warrants.” Id. at 815-16.

Because plaintiffs relied on their expert’s opinion that there was a defect common to

all GL 1800 motorcycles to meet the Rule 23(b)(3) predominance requirement and

because the district court must determine predominance before certifying a class, the

Seventh Circuit concluded that the district court could not defer a conclusive analysis

of the reliability and admissibility of this evidence to a later date.

The Eleventh Circuit applied American Honda’s holding in Sher v. Raytheon

Co., --- F. App’x ----, 2011 WL 814379 (11th Cir. Mar. 9, 2011) (unpublished) (Hill,

J.). The district court in Sher had certified a class despite marked differences between

the expert testimony presented by the parties, stating: 

[I]t is not necessary at this stage of the litigation to declare a proverbial

winner in the parties’ war of the battling experts or dueling statistics and

chemical concentrations . . . . This type of determination would require

the Court to weigh the evidence presented and engage in a Daubert style

critique of the proffered experts qualifications, which would be

inappropriate . . . . At this stage of the litigation, therefore an inquiry

into the admissibility of Plaintiffs’ proposed expert testimony as set forth

in Daubert would be inappropriate, because such an analysis delves too

far into the merits of Plaintiffs’ case.
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Sher, 2011 WL 814379, at *2 (second and third alterations in original) (quoting the

district court). The Eleventh Circuit reversed: 

The American Honda court found that, if the situation warrants, the

district court must perform a full Daubert analysis before certifying the

class. “A district court is the gatekeeper. It must determine the

reliability of the expert’s experience and training as well as the

methodology used. The [district] court must also resolve any challenge

to the reliability of information provided by an expert if that information

is relevant to establishing any of the Rule 23 requirements for class

certification.” We agree.

Id. at *3 (alteration in original) (internal citations omitted) (quoting Am. Honda, 600

F.3d at 815-16). The Eleventh Circuit went on to hold that the “district court erred as

a matter of law by not sufficiently evaluating and weighing conflicting expert

testimony on class certification. It was error for the district court to decline to declare

a proverbial, yet tentative winner. The Plaintiffs are required to prove, at the class

certification stage, more than just a prima facie case, i.e., more than just a ‘pretty good

case.’” Id. (internal citations omitted). 

If I were to reach the issue, I would join the Seventh and Eleventh Circuits and

resolve this open question in our circuit by requiring district courts to conduct a full

Daubert analysis before certifying a class whenever an expert’s opinion is central to

class certification and the reliability of that opinion is challenged. I reach this

conclusion for a number of reasons. First, the 2003 amendments to Rule 23 removed

the provision that class certification “may be conditional.” See Miles, 471 F.3d at 39;

Fed. R. Civ. P. 23(c)(1)(C). Requiring a full Daubert analysis is a natural extension

of the concept that class certification should not be conditional and should be

permitted only after a rigorous application of Rule 23’s requirements. See Wal-Mart

Stores, 564 U.S. ---, 2011 WL 2437013, at *7-8; Miles, 471 F.3d at 39-41. 
-36-

Second, I find it counterintuitive to allow district courts to utilize inadmissible

expert testimony to resolve factual disputes at the class certification stage. In Blades,

we held that:

The preliminary inquiry at the class certification stage may require the

court to resolve disputes going to the factual setting of the case, and such

disputes may overlap the merits of the case. Nonetheless, such disputes

may be resolved only insofar as resolution is necessary to determine the

nature of the evidence that would be sufficient, if the plaintiff’s general

allegations were true, to make out a prima facie case for the class. The

closer any dispute at the class certification stage comes to the heart of the

claim, the more cautious the court should be in ensuring that it must be

resolved in order to determine the nature of the evidence the plaintiff

would require.

Blades, 400 F.3d at 567 (internal citations omitted). The purpose of conducting a

Daubert inquiry is to ensure the relevance and reliability of expert testimony. Lauzon

v. Senco Prods., Inc., 270 F.3d 681, 686 (8th Cir. 2001). “It is to make certain that an

expert, whether basing testimony upon professional studies or personal experience,

employs in the courtroom the same level of intellectual rigor that characterizes the

practice of an expert in the relevant field.” Kumho Tire Co. v. Carmichael, 526 U.S.

137, 152 (1999). These principles are equally applicable in the context of class

certification. See Dukes v. Wal-Mart Stores, Inc., 603 F.3d 571, 639 (9th Cir 2010)

(Ikuta, J., dissenting), rev’d, 564 U.S. ---, 2011 WL 2437013. The district court must

“assess all of the relevant evidence admitted at the class certification stage and

determine whether each Rule 23 requirement has been met, just as the judge would

resolve a dispute about any other threshold prerequisite for continuing a lawsuit.”

Miles, 471 F.3d at 42; see also In re Hydrogen Peroxide Antitrust Litig., 552 F.3d at

323 (“Expert opinion with respect to class certification, like any matter relevant to a

Rule 23 requirement, calls for rigorous analysis.”). 

Just as in American Honda, the district court’s statement in the instant case as

to the admissibility of Staehle and Blischke’s testimony and reports “is not even
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conclusory; it leaves open the questions of what portions of [the experts’] testimony

it may have decided (or will decide) to exclude.” Am. Honda, 600 F.3d at 816

(holding that the district court’s refusal to conclusively determine, before certifying

a class, whether the “expert report was reliable enough to support Plaintiffs’ class

certification request” was an abuse of discretion). “Like any other evidence, expert

evidence introduced to ‘establish a component of a Rule 23 requirement’ must be

reliable; it is not enough that the expert testimony is ‘not fatally flawed.’” Dukes, 603

F.3d at 639 (Ikuta, J., dissenting) (quoting Miles, 471 F.3d at 42); see also Pecover v.

Elec. Arts Inc., No. C 08-2820 VRW, 2010 U.S. Dist. LEXIS 140632, at *8 (N.D. Cal.

Dec. 21, 2010) (“Given that class actions consume vast judicial resources and that

many defendants face substantial settlement pressures as a result of class

certification, . . . it hardly seems appropriate to allow flimsy expert opinions to

buttress plaintiffs’ [Rule] 23 arguments. . . . [A] Daubert analysis of every challenged

expert opinion seems prudent in fulfilling the court’s obligation to ensure actual

conformance with [Rule] 23 . . . .”).

Plaintiffs advance two reasons why this court should not adopt the American

Honda standard. First, plaintiffs argue that mandating a full Daubert analysis at the

class certification stage “would render the ‘early practicable time’ language of Rule

23 virtually meaningless” and “would ignore limitations of the information available

to the experts created by . . . bifurcated discovery.” However, because class

certifications are no longer conditional, a district court should delay certifying a class

until it is satisfied that all Rule 23 requirements have been met, even if additional

targeted discovery is needed to assess the reliability of an expert’s opinions.

Importantly, requiring a district court to conduct a full Daubert analysis before

certifying a class discourages plaintiffs who may have no intention of proceeding to

a trial on the merits from submitting unreliable expert testimony for settlement

purposes. See Schleicher v. Wendt, 618 F.3d 679, 682-83 (7th Cir. 2010) (noting that

“certification substantially increases the settlement value” of suits); Wal-Mart Stores,

Inc. v. Visa U.S.A. Inc. (In re Visa Check/MasterMoney Antitrust Litig.), 280 F.3d 124,

145 (2d Cir. 2001) (“The effect of certification on parties’ leverage in settlement
11 Such a full Daubert analysis would have been particularly apt in this case as

the district court relied on the questionable expert testimony of Dr. Blischke when it

certified the breach of warranty class. According to the district court, Dr. Blischke

“concluded that the fittings have a mean time to failure of 40 years, which means

approximately half of the units will likely fail within 40 years and approximately half

will fail after.” In re Zurn Pex Plumbing, 267 F.R.D. at 556. However, this statement

is troublesome in two respects. First, Dr. Blischke did not conclude that the fittings

have a mean time to failure of 40 years; he assumed an average mean-time-to-failure

rate of 40 years—a number derived from a Zurn erosion test that showed that its

fittings did not display any erosion after 40 years. Second, Dr. Blischke’s assumption

is unreliable on its face: while no fitting failed in the Zurn test after 40 years’ worth

of water had passed through it, Dr. Blischke assumed that half of the fittings will fail

within 40 years. 

-38-

negotiations is a fact of life.”), overruled on other grounds by Miles, 471 F.3d 24;

Szabo, 249 F.3d at 675 (noting that class certification “puts a bet-your-company

decision to [defendant’s] managers and may induce a substantial settlement even if the

customers’ position is weak”). 

Second, plaintiffs argue that mandating a full Daubert analysis at the class

certification stage “is also unnecessary because expert opinions at class certification

are considered by an Article III judge” and not by a jury. The court agrees with this

position. Ante at 10. I believe, however, that this argument misses the mark. Our

concern should not be that the district judge cannot weigh admissible expert testimony

properly. We should be concerned, instead, that the case will proceed beyond class

certification on the basis of inadmissible, unreliable expert testimony. “[E]xpert

testimony that is not scientifically reliable should not be admitted, even ‘at this early

stage of the proceedings.’” Am. Honda, 600 F.3d at 819 (internal quotation marks

omitted). 

As such, were I to reach this question in the instant case, I would reverse the

district court’s decision to certify the breach of warranty class and the negligence class

and remand the case to the district court to conduct a full Daubert inquiry as to the

admissibility of Staehle and Blischke’s testimony.11
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II. CONCLUSION

Because I would conclude that the dry plaintiffs have failed to allege an injury

in fact and, therefore, lack standing, and because individual issues predominate over

common issues for those plaintiffs remaining in the breach of warranty class, I would

reverse the district court’s certification of the breach of warranty class. Because I

would conclude that individual issues predominate over common issues for those

plaintiffs in the negligence class, I would reverse the district court’s certification of

the negligence class as well. Thus, I respectfully dissent. 

______________________________