This educational guide is based on the linked primary sources. It is not a Court publication, is not affiliated with the Court, and is not legal advice.
In brief
Overview
According to Petitioners, the dispute centers on whether the adequacy of expert evidence for class certification is a merits question rather than a procedural issue.
The parties discuss the applicability of the Daubert standard to the admissibility of expert testimony.
According to Comcast, both parties agree that if the Daubert question had not been waived, a hearing on the expert report’s admissibility should have been held.
Justice Ginsburg asked whether the proposed settlement affects the Court’s consideration of the case.
Background and question before the Court
Justice Ginsburg asked if the argument was limited to the determination of damages.
Justice Ginsburg asked why not (referring to the merits question).
Justice Sotomayor asked Mr. Estrada to state the legal rule the Court should articulate.
Justice Kagan asked whether evidence that is inadequately probative is inadmissible.
According to Justice Kagan, justice Kagan said she was still searching for a legal question that any party disagrees about.
Justice Alito asked whether a district court may certify a class action under the circumstances.
Justice Alito asked whether the issue was a factual matter of the record.
Justice Sotomayor asked what the district court found when it accepted the expert’s theory as adequate.
Justice Breyer asked whether prior cases such as Learned Hand, Alcoa, and United Fruit apply to the present issue.
- [1] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 3
- [2] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 4
- [3] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 22
- [4] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 31
- [5] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 40
- [6] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 41
- [7] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 42
- [8] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 46
- [9] a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdf, p. 54
What each side argues
Petitioners (Comcast Corporation)
Petitioners argue that the Third Circuit held that assessing the adequacy of expert evidence for class certification is a merits question, not part of the certification inquiry.
According to Comcast, petitioners state that the legal standards are agreed upon and that if the Daubert issue had not been waived, a hearing on admissibility should have been held.
According to Comcast, petitioners contend that the district court found the McClave damages model persuasive enough for class‑wide damages.
According to Mr. Barnett, petitioners note that they never cited Daubert and that their objection was to admissibility, not weight, of the expert report.
Respondents (Caroline Behrend)
Source-limited. The record does not yet support a complete account.
What happened at oral argument
Oral argument began at 10:04 a.m. before the Supreme Court of the United States.
What the Court decided
Why it matters
Terms to know
No glossary terms are available for this guide.
Primary sources
Read the source materials on the official site or open the immutable repository copy used for this guide.
- a7f25eaf0634a44aa503-r1-9a6bd468829792f6.pdforal argument transcript
Guide generated September 24, 2026. Automated validation accepted this version.