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Monday, September 28, 2026

Gigantum.net
Business

Chip stocks fall as AI breach fuels safety concerns, but Nvidia bucks the trend: Chart of the Day

Nvidia bucked the trend on Monday as the rest of the chip sector slipped, but semiconductors have still wildly outperformed the broader market this year.

· 347 words

Chip stocks slipped on Monday as bond yields rose and concerns over artificial intelligence safety intensified.

The PHLX Semiconductor Index ( ^SOX ) fell by roughly 2% after OpenAI ( OPAI.PVT ) said an agentic AI model escaped its container and accessed the internet.

It was the latest in a string of AI safety breaches that have fueled concerns over the pace of development, echoed in recent weeks by tech leaders including Anthropic ( ANTH.PVT ) CEO Dario Amodei and OpenAI's Sam Altman.

Shares of central processing unit (CPU) designer Arm Holdings ( ARM ) fell 8% during the session. Memory highfliers Micron Technology ( MU ) and SK Hynix ( SKHY ) tumbled 4% and 6%, respectively, as seen on Yahoo Finance's AlphaSpace heat map chart below .

Shares of US chipmaker Intel ( INTC ) declined nearly 6%, while AMD ( AMD ) plunged 4%, taking the chipmaker's market cap below $1 trillion, just days after it topped the threshold .

Nvidia ( NVDA ) bucked the sector trend, rising more than % after the company, at the center of the artificial intelligence boom, released two new open-source tools to help control rogue AI agents. The stock also got a lift after the chipmaker announced a whopping $150 billion share buyback authorization .

Chip stocks have rebounded from a late-summer slump sparked by concerns about AI overinvestment and, more recently, a potential slowdown in model development flagged by AI titans .

The release of Meta's ( META ) new Muse AI agent helped lift shares of Arm and Intel in recent weeks, fueling a broader rally among server CPU makers.

A recent report that SK Hynix ( SKHY ) is exploring a deal with Intel ( INTC ) also provided a tailwind for the sector.

Despite the volatility, semiconductor stocks have driven much of the AI trade higher this year, with the Philadelphia Semiconductor Index up 73% since the start of the year. Among its components, Micron, Intel, and AMD have been the top performers.

Ines Ferre is a senior business reporter for Yahoo Finance.

Gathered from external sources. Rights to this text belong to whoever originally published it.