Alphabet Shares Slide 0.41% on 10th-Highest U.S. Trading Volume as Antitrust Pressures Mount

On September 8, 2025, , , . . equities, reflecting heightened regulatory scrutiny and market uncertainty.

Alphabet faces mounting antitrust pressures as the U.S. Department of Justice (DOJ) pushes for structural remedies to dismantle its dominance in digital advertising. A September 2025 court ruling mandated that Google share search data with competitors and prohibit exclusive contracts for six years, challenging its control over publisher ad markets. The DOJ has also reportedly sought the potential divestiture of Google’s Ad Manager division, a critical component of its advertising infrastructure. Legal experts suggest these measures could fragment Alphabet’s ad tech ecosystem, though the company argues such actions risk harming small businesses and advertisers reliant on its platform.

PubMatic’s antitrust lawsuit against Google further complicates the landscape, alleging anticompetitive practices that suppress competition. While the case could accelerate market shifts, Alphabet’s preemptive steps to prepare its ad tech unit for independence signal a strategic response to regulatory expectations. Analysts remain divided: some warn that compliance costs and operational disruptions may weigh on Alphabet’s near-term performance, while others highlight its long-term resilience through AI-driven ad innovations and a vast ecosystem.

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