Clarifying Ascertainability in Rule 23(b)(3) Class Actions: Objective Criteria and Feasible Identification Mechanisms

Introduction

The Third Circuit’s decision in Bridget McMahon v. Chipotle Mexican Grill, Inc. (Nos. 24-1883 & 24-2042) addresses two central issues: (1) the proper application of the Rule 23(b)(3) “ascertainability” requirement for class certification, and (2) the viability of individual statutory and common-law claims—specifically tort, contract, and consumer‐protection causes of action—after summary judgment. The dispute arose in the wake of a nationwide coin shortage during the COVID-19 pandemic. Plaintiffs Bridget McMahon and James Rice alleged that Chipotle cashiers routinely refused to give customers coin change when they paid with bills, thus misappropriating small sums of money. They sought class certification under Federal Rule of Civil Procedure 23(b)(3) and advanced claims for misappropriation, conversion, violation of Pennsylvania’s Unfair Trade Practices and Consumer Protection Law (UTPCPL), breach of contract, and unjust enrichment. The District Court denied certification for lack of a reliable, administratively feasible identification mechanism, granted summary judgment for Chipotle on all individual claims, and entered final judgment in Chipotle’s favor. Rice appealed the certification and summary-judgment rulings; Chipotle cross-appealed the denial of its motion to exclude expert testimony. The Third Circuit affirmed the certification denial, vacated parts of the summary-judgment decision (barring tort and unjust‐enrichment claims but reviving breach-of-contract and UTPCPL “catchall” claims), and dismissed the cross-appeal as moot.

Summary of the Judgment

1. Class Certification (Rule 23(b)(3))
• The plaintiffs defined the class as all cash‐paying customers at Chipotle Pennsylvania restaurants since January 1, 2020, who received less coin change than they were due. Although the definition relied on objective criteria, the court held plaintiffs failed to demonstrate a reliable, administratively feasible means of identifying class members. Chipotle’s electronic transaction data did not record whether coin change was dispensed; security video footage could not distinguish between rounding down prices and withholding coins; and affidavits from alleged victims could not be corroborated without mini-trials. The Third Circuit affirmed the denial of certification for lack of “ascertainability.”

2. Summary Judgment on Individual Claims
• Tort Claims (Misappropriation & Conversion): barred by Pennsylvania’s gist-of-the-action doctrine because the dispute over correct change sounded in contract, not in tort.
• Unjust Enrichment: unavailable where an express contract governed the payment–food exchange.
• Breach of Contract: plaintiffs may proceed. The court vacated summary judgment on this claim, concluding that Rice’s in‐store inquiry and challenge to the missing coins did not constitute an express or implied waiver of the original payment terms.
• UTPCPL Claims: summary judgment was proper on the false-advertising theory because Rice did not rely on menu prices when ordering. But the court revived the “catchall” provision claim (§ 201-2(4)(xxi)), holding that withholding coin change without notice could mislead a reasonable consumer and that Rice justifiably relied on the cashier’s conduct to his detriment.

Analysis

1. Precedents Cited

Marcus v. BMW of North America, LLC, 687 F.3d 583 (3d Cir. 2012) – established the two‐part test for ascertainability: (a) class definition by objective criteria, and (b) a reliable, administratively feasible identification mechanism.
Byrd v. Aaron’s, Inc., 784 F.3d 154 (3d Cir. 2015) – clarified that courts need only show class members can be identified, not that they have already been identified; emphasized “rigorous analysis.”
Kelly v. RealPage, Inc., 47 F.4th 202 (3d Cir. 2022) – rejected the notion that sheer volume of records can justify a finding of unascertainability, but confirmed that if records lack required data or mini-trials would be unavoidable, ascertainability fails.
Ramsay v. National Board of Medical Examiners, 968 F.3d 251 (3d Cir. 2020) – upheld district court fact‐findings on the limits of surveillance footage as ascertainment evidence.
Bruno v. Erie Insurance Co., 106 A.3d 48 (Pa. 2014) – articulated Pennsylvania’s gist-of-the-action doctrine distinguishing tort from contract duties.
SodexoMAGIC, LLC v. Drexel Univ., 24 F.4th 183 (3d Cir. 2022) – reaffirmed that purely contractual duties cannot sustain tort claims under Pennsylvania law.
13 Pa. Cons. Stat. § 2607(c)(1) – Pennsylvania UCC requirement of timely notice of contract breach when nonconforming goods are tendered.
73 Pa. Cons. Stat. §§ 201-2(4)(ix), 201-2(4)(xxi), 201-3 – statutory provisions defining UTPCPL prohibitions and deceptive practices.

2. Legal Reasoning

a. Ascertainability under Rule 23(b)(3)
The court applied the two‐pronged Marcus test. It agreed that the class definition used objective criteria (cash payments and under-change events), but it found no reliable, administratively feasible mechanism for identifying shortchanged customers. Chipotle’s point-of-sale system logs bill transactions but omits coin dispensation data; security camera footage cannot reveal whether a cashier rounded price or withheld coins; and customer affidavits would require individual credibility assessments. Relying on Kelly, the court emphasized that unascertainability arises not from scale, but from the absence of objective records or the need for “mini-trials” to verify membership. The Third Circuit found no abuse of discretion in the District Court’s meticulous fact‐finding.

b. Gist of the Action and Tort-Contract Distinction
Under Pennsylvania’s gist-of-the-action doctrine, tort claims are barred if the duty breached is solely contractual. Rice’s misappropriation and conversion allegations—that cashiers failed to give proper change—stem from Chipotle’s express promise to exchange food for exact payment. Without an independent noncontractual duty (e.g., premises safety in Bruno), tort theories cannot proceed.

c. Unjust Enrichment vs. Express Contract
Pennsylvania law precludes unjust enrichment when an express contract governs the relationship. Here, the parties undisputedly contracted at the register for a set price in exchange for food.

d. Breach of Contract and Waiver Analysis
Rice’s complaint and in‐store inquiry demonstrably challenged the missing coins. The District Court construed Rice’s acceptance of bills‐only change as an implied waiver of the original contract terms. The Third Circuit held that a reasonable jury could instead find that Rice sought to enforce the receipt’s terms by other means and did not waive his right to correct change.

e. UTPCPL Catchall Provision (§ 201-2(4)(xxi))
To prevail, a plaintiff must show misleading or deceptive conduct creating consumer confusion, and justifiable reliance to financial detriment. Rice’s evidence—that he paid cash, was not warned about missing coins, discovered the shortfall only upon inquiry, and left 45 ¢ short—supports a claim that Chipotle’s conduct misled a reasonable customer and induced reliance.

3. Impact

Ascertainability Clarified: Courts will scrutinize the defendant’s own records to ensure they actually capture the disputed event. Absent objective data, reliance on surveillance or affidavits alone may doom class certification.
Administrative Feasibility: The decision reinforces that “mini-trials” to authenticate class membership undermine Rule 23(b)(3) certification; parties must propose streamlined, verifiable methods.
Contract vs. Tort in Consumer Disputes: The ruling underscores the reach of the gist-of-the-action doctrine and the limits of tort remedies for purely contractual disputes in Pennsylvania.
Consumer-Protection Claims: The revival of UTPCPL catchall claims signals that point-of-sale practices which surprise or mislead purchasers can trigger statutory remedies, even where formal advertising claims are absent or inapplicable.

Complex Concepts Simplified

Ascertainability Requirement: Before certifying a class, courts ask: (1) Is the class defined by clear, objective rules? (2) Can we actually identify who belongs to the class without dozens of individual mini-trials? If the answer to either is “no,” certification fails.
Gist-of-the-Action Doctrine: In Pennsylvania, you cannot turn a contract breach into a tort claim unless there is an independent legal duty outside the contract. If the only broken promise is the promise to pay or deliver goods, your claim is contractual, not tort.
UTPCPL Catchall Provision: Beyond specific unfair trade practices, any deceptive act that likely confuses consumers can be actionable. You must show you were misled and suffered a loss because of it.
Waiver vs. Breach: Accepting part of a changed agreement does not always mean you gave up your right to the original deal. If you protest or ask questions, you may preserve your breach‐of‐contract claim.

Conclusion

The Third Circuit’s decision in McMahon v. Chipotle delivers important clarifications for both class‐action and individual consumer disputes. It affirms that class certification under Rule 23(b)(3) requires not only objective definitions but also a practicable way to identify members without individualized proof. It reaffirms the bar on contractual disputes dressed up as torts under Pennsylvania’s gist-of-the-action doctrine, while preserving genuine contract and consumer‐protection claims. For practitioners, the decision underscores the need to assess carefully the data and processes available for ascertainment and to distinguish sharply between contractual and extra-contractual duties in consumer transactions. Its guidance will shape class certification strategies and consumer-litigation tactics in the Third Circuit and potentially beyond.