The news: Adam Mosseri, head of Instagram, testified Wednesday that heavy social media use does not equal clinical addiction. In a Los Angeles courtroom, he argued that overuse is subjective and said it would be shortsighted for Meta to profit at the expense of user well-being. 

He compared scrolling too long on Instagram to binge-watching a series on Netflix, framing the behavior as personal rather than pathological, per CNBC.

The case centers on whether design features such as infinite scroll contributed to a teen plaintiff’s mental health struggles. 

• It’s a bellwether for thousands of similar suits moving through state and federal courts. 
• Two defendants, TikTok and Snap, have already settled. Meta, YouTube, and others are fighting on design, liability, and the definition of addiction.

For marketers, the takeaway is less about semantics and more about exposure. Brands appearing alongside features framed as potentially harmful could be singled out by advocacy groups and plaintiffs’ attorneys connecting ad dollars to disputed mechanics.

Zooming in: Internal documents surfaced in discovery show Meta researchers had flagged rising body image concerns among teen girls years ago, according to reporting from The Wall Street Journal and congressional exhibits. 

• Plaintiffs argue those findings undercut Mosseri’s framing of overuse as merely “personal.” 
• They contend that features such as infinite scroll, algorithmic ranking, and push notifications were engineered to extend session time—especially among younger users.

“We make less money from teens than any other demographic on the platform,” Mosseri said Wednesday. “Teens don’t click on ads and they don’t have much expendable income.”

The jury will weigh whether Instagram was a “substantial factor” in harm. The verdict could shape platform design, disclosure, and brand adjacency.

Implications for advertisers: Depending on how the trial leans, advertisers may face questions about adjacency, targeting practices, and youth exposure. Media plans tied to teen engagement could face scrutiny in future suits.

A court ruling against Meta would harden the narrative that engagement design equals harm. Brands aligned with “time spent” KPIs may need to rethink success metrics.

• Advertisers need to audit youth targeting and model scenarios where teen engagement drops. 
• Diversify beyond platforms under active litigation. Align KPIs with quality attention, not raw session time.

If the court narrows how feeds work, expect it to ripple into reach, pricing, and brand safety standards across social media advertising.

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