Lead: On Feb. 11, 2026, Instagram head Adam Mosseri testified in a California courtroom that social media is not “clinically addictive,” disputing claims in a bellwether trial that platforms prioritized engagement over teen mental health. Mosseri, 43, told the court Instagram tests features used by young people before release and framed the company as a steward of safety. The case, brought by a 20-year-old plaintiff known as K.G.M., seeks damages and design changes and could set a precedent for dozens of related lawsuits. The trial pits claims of addiction-like harms against tech firms’ defenses and federal legal protections.
Key Takeaways
- Adam Mosseri, Instagram’s chief executive, testified on Feb. 11, 2026, in the bellwether trial that social media is not “clinically addictive.”
- The plaintiff is a 20-year-old California woman identified in filings as K.G.M.; a win for her could unlock broad monetary damages and force app redesigns.
- The suit is among a flood of lawsuits from teenagers, schools and state attorneys general accusing platforms of addiction-level harms comparable to slot machines and cigarettes.
- Mosseri emphasized Instagram tests features used by young people before rollout and framed the company as balancing safety and speech.
- Defendants, including Meta and YouTube, argue there is no scientific consensus that platforms cause clinical addiction and cite federal protections for online publishers.
- The trial is being watched as a potential barometer for liability exposure and regulatory pressure on major platforms.
Background
The litigation is part of a growing wave of cases filed since roughly 2020 alleging that social apps contributed to mental-health harms among minors. Plaintiffs have sought to hold major platforms accountable for design choices they say encourage compulsive use, citing parallels to gambling and tobacco litigation. Tech companies counter that existing research does not establish a causal link to clinical addiction and that federal law limits liability for third-party content. The legal fight also intersects with broader policy debates over platform safety measures, youth privacy protections and the limits of intermediary immunity.
Instagram, owned by Meta, has repeatedly defended its policies and engineering practices as safety-minded while acknowledging trade-offs inherent in product design. Adam Mosseri has led Instagram since 2018 and has frequently testified publicly about content moderation and features aimed at teenagers. Regulators, state attorneys general and advocacy groups have pressed for stronger safeguards and more transparency about how algorithms influence young users. The current bellwether case was selected to test core legal arguments that could influence many related suits nationwide.
Main Event
On the first day of testimony for tech-company executives, Mosseri appeared in court and told judges and jurors that Instagram does not meet the clinical threshold for addiction. He described the company’s process for testing features targeted at young people and stressed that some engagement outcomes can be harmful even when not intended. Mosseri drew a distinction between heavy use and a clinical diagnosis, saying people can be highly engaged in an app the way they are engaged by a popular TV show without meeting clinical criteria.
He also acknowledged a tension between safety and expression, saying the company aims “to be as safe as possible and censor as little as possible.” Mosseri was the first senior executive to testify in a case that directly challenges the design and business incentives of major platforms. Plaintiffs argued in opening statements and filings that features and algorithms were intentionally optimized to maximize time-on-platform, contributing to harms for some adolescent users.
The defendants broadly pressed that the scientific record does not show social media causes clinical addiction, and that established federal protections constrain liability for user-posted content. Court filings emphasize that liability would hinge on proving company conduct crossed legal lines beyond ordinary speech and product choices. Observers say the judge’s rulings on admissible evidence and expert testimony will be decisive for how widely any verdict might apply.
Analysis & Implications
If the plaintiff secures a favorable verdict, the financial stakes could be substantial, with the potential for large damages awards and injunctions requiring product changes. Beyond dollars, a finding of legal responsibility could prompt industry-wide design shifts, from algorithmic tweaks to limits on certain youth-facing features. Companies may respond by accelerating safety tech, increasing disclosures, or altering recommender systems to reduce engagement incentives.
Conversely, a defense win could dampen the momentum of similar suits and reinforce current legal protections for platforms, especially if the court reinforces federal immunity doctrines. The outcome may also shape legislative agendas: a verdict against platforms could spur lawmakers to pursue standardized safety rules for minors, while a defense victory might shift focus to research funding and voluntary best practices. Investors and advertisers will monitor the trial for signals about regulatory risk and user-reputation exposure.
Practically, the case highlights the challenge of translating public-health concerns into legal causes of action. Courts will grapple with expert disputes over definitions — distinguishing heavy or problematic use from clinically diagnosed addiction — and with whether platform design choices constitute actionable misconduct. The trial’s evidentiary record could clarify how courts treat behavioral-science testimony, algorithmic design documentation and internal company communications.
Comparison & Data
| Claim | Plaintiffs’ Position | Platforms’ Defense |
|---|---|---|
| Addiction | Use comparable to slot machines and cigarettes; leads to addiction-like harms | No scientific consensus that social media causes clinical addiction |
| Design Incentives | Features and algorithms optimized to maximize youth engagement | Companies test features for safety and balance speech concerns |
| Liability | Design choices make companies responsible for harms | Federal law and user-post protections limit publisher liability |
The table summarizes central legal and factual disagreements at issue in the litigation. While plaintiffs emphasize behavioral parallels to regulated harms, defendants stress gaps in causal proof and statutory shields. The judge will need to assess expert evidence on both behavioral science and industry practices to determine whether allegations rise to legally cognizable harms.
Reactions & Quotes
The courtroom exchanges drew immediate reactions from both sides and observers.
“Social media is not ‘clinically addictive,'”
Adam Mosseri, Instagram chief executive, Feb. 11, 2026 testimony
Mosseri used this line to reject the characterization at the heart of plaintiffs’ claims while acknowledging platforms can produce harmful outcomes for some users. He framed the company’s role as balancing safety and expression.
“Comparable to slot machines at casinos and cigarettes,”
Plaintiffs’ court filings
Plaintiffs’ filings use this comparison to argue the scale and character of harms; their legal theory relies on showing that design choices materially increased risk of addiction-like outcomes for minors.
“There’s always trade-off between safety and speech,”
Adam Mosseri, courtroom testimony
This remark underscored Mosseri’s framing of difficult policy choices inside product development and framed regulatory remedies as potentially constraining user expression alongside safety gains.
Unconfirmed
- Whether specific Instagram features cited by plaintiffs directly caused the plaintiff’s harms remains unproven in court at this stage.
- The extent to which federal immunity statutes will shield defendants from the novel legal theories raised here is still pending judicial interpretation.
- Any ultimate damages amount or required product changes are speculative until a final judgment or settlement is reached.
Bottom Line
The Feb. 11 testimony by Adam Mosseri crystallizes the core dispute in a high-stakes trial: plaintiffs say platform design produced addiction-like harms for minors; defendants deny a causal, clinical link and invoke legal protections. The case is a bellwether — its outcome could either accelerate regulatory and design changes across the industry or reinforce existing legal and operational frameworks that shield platforms.
Watch for the court’s rulings on expert admissibility and whether the judge permits the jury to consider behavioral-science evidence as proof of clinical-level harm. Those procedural decisions will shape not only this trial’s trajectory but also the posture of related lawsuits and potential legislative responses.
Sources
- The New York Times (news report on courtroom testimony and trial overview)