Unreported / Non-Citable
Background
Plaintiffs in this multidistrict litigation, suing through their guardians ad litem, allege that lead and arsenic in Defendants' baby food caused them to develop autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD). The court phased discovery, starting with general causation. At 2024 case management conferences, the court and parties framed that question in two parts: whether heavy metals can cause ASD and ADHD in young children, and whether the metal levels in Defendants' products could cause those injuries through consumption.
After a multi-day Daubert hearing, the court in February 2026 granted Defendants' motions to exclude Plaintiffs' general causation experts, concluding Plaintiffs had not met their burden under Federal Rule of Evidence 702. Plaintiffs had also offered no evidence on cadmium or mercury, so they abandoned any causation theory based on those metals. Defendants then moved for summary judgment, arguing that without admissible general causation evidence an essential element of the toxic tort claims fails. The court heard argument on August 13, 2026.
The Court’s Holding
The court granted summary judgment for Defendants. Absent the excluded experts, Plaintiffs had no admissible evidence on general causation. The court rejected the argument that judgment was premature without discovery on any individual plaintiff's actual exposure: bifurcating causation discovery is permissible in toxic tort cases, Plaintiffs must prove both general and specific causation, and they conceded the exclusion ruling would apply in the individual cases. It also rejected Plaintiffs' claim that the Daubert ruling rested only on temporality, noting the earlier order identified various Rule 702 deficiencies.
Plaintiffs who direct-filed in the MDL after expert reports were served on May 23, 2025, but by the November 21, 2025 cutoff, are bound by the ruling. The court had said in March 2025 that a joinder deadline was needed so plaintiffs would be bound one way or the other. Those plaintiffs filed voluntarily through counsel appointed to the Plaintiff Steering Committee, the Daubert hearing did not occur until December 2025, and they could have sought more expert discovery or other relief. The court found no due process violation and held Taylor v. Sturgell, which concerned nonparties, inapposite.
The relief is limited. The order covers cases direct filed or transferred into the MDL as of November 21, 2025, and only claims of neurological injury manifesting as diagnosed ASD or ADHD. It does not reach infant formula claims or claims of other injuries, such as IQ loss, language disorders, learning disabilities, or sensory-processing disorders; the court held those injuries were outside the general causation inquiry and not abandoned. Judgment is entered in full in the Exhibit A cases. In the Exhibit B and C cases, summary judgment covers all claims except formula and non-ASD/ADHD injury claims, and the court found separate Rule 54(b) judgment warranted to allow an immediate appeal. Plaintiffs' motions to exclude Defendants' experts were denied as moot, without prejudice. Claims against retailer defendants in the Watkins case were not addressed because that case was remanded for lack of subject-matter jurisdiction.
Key Takeaways
- Once a court excludes a plaintiff's general causation experts under Rule 702, summary judgment follows if no other admissible evidence on that element exists.
- Bifurcating discovery into general and specific causation phases is permissible in toxic tort litigation, and the court did not require individual exposure discovery first.
- Plaintiffs who direct-filed before the November 21, 2025 cutoff are bound by the Daubert ruling because they had notice through counsel and a chance to be heard before it was decided.
- The order does not dispose of infant formula claims or claims of injuries other than diagnosed ASD or ADHD, and the court refused to treat those claims as abandoned.
- Separate Rule 54(b) judgment was found warranted in the Exhibit B and C cases so the ASD/ADHD general causation ruling can be appealed without piecemeal review.
Why It Matters
The order shows how deciding general causation first in an MDL can resolve the core theory of many cases at once when expert testimony is excluded. It also confirms that the court will bind plaintiffs who joined before a stated cutoff, even after expert reports were exchanged, where they had notice and their counsel took part in the hearing.
This is a district court order, not a published appellate precedent. Because the court found Rule 54(b) judgment warranted in the Exhibit B and C cases, an appeal may bring the underlying Rule 702 exclusion and this summary judgment ruling before the Ninth Circuit. Formula claims and non-ASD/ADHD injury claims remain open; under Pretrial Order No. 15, additional injuries are not considered in the MDL but may be preserved for the transferor courts.