Published September 30, 2026
Meta CEO Mark Zuckerberg and Instagram head Adam Mosseri will likely be back on the witness stand this fall. Los Angeles Superior Court Judge Carolyn Kuhl has rejected Meta's motion to quash the subpoenas requiring both executives to testify at the next social media addiction trial in California's coordinated state-court proceeding, set to begin October 28, 2026, The Recorder reported on September 29.
The upcoming trial combines the claims of two young plaintiffs identified by their initials: S.J., a 15-year-old from Illinois, and K.D.B., an 18-year-old from Mississippi. Judge Kuhl ordered on August 28 that their cases be heard together by one jury, over Meta's objection that a two-plaintiff trial would confuse jurors. Both plaintiffs settled with TikTok in August, leaving Meta, YouTube, and Snap as the remaining defendants. A third plaintiff originally slated for October, P.M.Y., dropped the remaining claims.
Heading into the September 29 final status conference, the defendants also asked the court to let jurors hear that attorney advertising played a role in the families' decisions to sue, arguing it bears on credibility. How the court ruled on that request had not been widely reported at publication time.
This would not be Zuckerberg's first time testifying before a jury in this litigation. He took the stand on February 18, 2026, in the first bellwether trial in the same proceeding, which ended in a verdict finding Meta and YouTube liable. Mosseri testified in August during a state attorney general trial. Executives often argue that they should not be forced to testify when others in the company could answer the same questions; the ruling means that argument did not keep either off the witness list here.
The California state cases run alongside the federal social media addiction MDL, where more than 3,000 cases are pending. Personal injury and school district claims were carved out of Meta's recent settlement with state attorneys general and continue to move toward trial.
If your child developed anxiety, depression, an eating disorder, or other harms linked to compulsive social media use, see Atumio's social media addiction case page for a free eligibility review, or start your case review directly.