Arm Plunges 9.29 as 1.34B Volume Ranks 86th on AI Partnership Concerns and Tech Sector Selloff

On October 10, 2025, Arm Holdings (ARM) closed with a 9.29% decline, marking its lowest daily performance since a key regulatory decision earlier this year. The stock traded with a volume of $1.34 billion, ranking 86th in overall trading activity on the day. The sell-off appears linked to a combination of sector-wide pressure and specific corporate developments.

A newly announced partnership with a major Asian semiconductor manufacturer raised questions about long-term licensing revenue sustainability. While the collaboration aims to optimize chip design for AI applications, analysts noted the agreement includes royalty reductions for certain embedded systems, potentially impacting near-term margins. This came alongside broader weakness in the tech sector as investors reassessed growth projections for 2026.

Separate disclosures highlighted operational challenges in scaling manufacturing capacity for next-generation 3nm architecture. The company acknowledged delays in securing foundry commitments, though emphasized these would not affect existing product roadmaps. Market participants interpreted the admission as a sign of intensifying supply chain constraints, particularly in high-performance computing segments.

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