AMD hits a major milestone as AI stocks blaze higher

By Britney Nguyen

AMD becomes the 14th U.S. company to see its market capitalization top $1 trillion

AMD's stock rose Monday alongside shares of other companies that make central processing units for servers.

Shares of Intel, Advanced Micro Devices and other hardware companies stormed higher on Monday in a show of intense investor appetite for the artificial-intelligence trade.

Arm Holdings' (ARM) U.S.-listed shares were up 17.1% at the market close, while Intel's stock (INTC) closed up 12.1%. Advanced Micro Devices' stock (AMD) finished the day up 9.9%, marking a record close.

AMD shares finished the day at $615.52, translating to a market capitalization of $1 trillion.

Only 13 other U.S. companies have crossed the $1 trillion mark, according to Dow Jones Market Data. And AMD shares have seen an extreme rally: The company was worth $255 billion at this point last year.

Arm, AMD and Intel are all in the business of making central processing units for artificial-intelligence servers. This corner of the chip market has seen momentum in recent months, driven in part by the proliferation of AI agents, or services that can act autonomously on behalf of users. And Meta Platforms' (META) Muse, a consumer-focused AI agent, is garnering buzz since launching earlier this month.

Mizuho analyst Daniel O'Regan said AI agents have driven a "full-blown feeding frenzy" in chip and networking stocks Monday, reflecting that investors are "finally starting to connect the dots on what" the Muse launch signals for AI infrastructure demand.

"People are realizing Muse isn't a chatbot," and therefore the market is starting to understand that agentic workloads are different from those for AI-driven searches and conversations, O'Regan said in a note to clients.

Agents like Muse run constantly in the background and can handle multiple tasks, which "has much bigger compute implications than a simple chatbot query," he said, referring to computing power.

O'Regan added that Muse's successful launch has investors now questioning when OpenAI, Anthropic, Google (GOOGL) (GOOG) and other AI players will launch similar AI agents - that's when "the infrastructure math starts to get crazy," he said.

The PHLX Semiconductor Index SOX rose 4.3% on Monday.

Another driver of AI stock momentum could be news from the last few days surrounding Anthropic and OpenAI, according to a note from Jeffrey Favuzza, an equities-trading analyst at Jefferies.

Anthropic announced Friday afternoon that it will work with consulting firm Accenture (ACN) to independently evaluate frontier AI models, or those deemed to be on the cutting edge. Both Anthropic and Accenture expect to invest at least $1 billion in the effort over the next five years, according to the company behind the Claude AI model. Under the agreement, Anthropic said embedded evaluators will have similar access as employees to assess model development and deployment.

The partnership comes after Anthropic CEO Dario Amodei published an essay earlier this month calling for a slowdown in the development of leading-edge AI models. Investors have generally gotten more concerned about AI safety.

The Wall Street Journal also reported Friday that Anthropic is planning to hold its initial public offering in November. The Journal noted that investors expect Anthropic's offering to raise up to $100 billion, while the New York Times reported Friday that the company could see up to $100 billion in annualized revenue by year-end.

Anthropic could share financial paperwork for its IPO in the coming weeks, the New York Times reported, citing people speaking on condition of anonymity. Reuters reported that Anthropic could release a new AI model before its IPO, as it faces steep competition with OpenAI after that company's launch of GPT-6 Astra.

Favuzza also pointed to a report from the Financial Times saying that OpenAI expects its revenue to jump almost 10 times, from $36 billion this year to $350 billion by the end of the decade, although it could also spend about $280 billion on computing power over that period.

Mizuho's O'Regan said in a separate note to clients that the headlines around both AI startups "reinforce expectations for sustained AI infrastructure spending."

Meanwhile, shares of networking provider Ciena (CIEN) were up 4.9% at Monday's close after an upgrade by Evercore ISI analyst Amit Daryanani, who moved from an in-line rating to an outperform rating on the stock.

Daryanani said the company is "an attractive way to gain exposure to the optical networking space," which has become a bottleneck in the AI data-center buildout.

Ciena's offerings are "purpose built to address" the connectivity demands of AI data centers given the company's full focus on optical systems, Daryanani said in a Monday note to clients.

-Britney Nguyen

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09-21-26 1619ET

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