Broadcom shares fell 4% after Chief Executive Officer Hock Tan's warning on capital spending cast a shadow over the AI chip sector. Marvell Technology matched the decline. Both stocks closed down 4% on the day.

The sell-off centers on Tan's comments about capital intensity. Investors read his warning as a signal that the cost of sustaining AI chip growth may be rising faster than revenue. Broadcom and Marvell sit at the center of that trade. Both companies design custom AI silicon and sell networking chips to hyperscale data center operators.

Why does the CEO's warning matter?

Hock Tan has built Broadcom's recent growth story on AI. Custom accelerators and networking parts now drive a large share of the company's semiconductor revenue. Any statement from Tan about capital requirements therefore moves the stock directly.

A capital warning from a CEO carries weight because it touches the core question in AI chips: how much spending is required to keep the growth curve intact. When the answer suggests higher costs, markets reprice the entire custom-silicon group. Marvell's identical 4% drop shows the read-across was immediate.

Neither company disclosed new financial figures in the report. The moves reflect investor interpretation of the chief executive's spending signal rather than a change in reported results.

How broad was the damage?

The decline hit the two named names in the custom AI silicon market. Key facts from the session:

• Broadcom shares fell 4%.
• Marvell shares fell 4%.
• The trigger was a capital spending warning from CEO Hock Tan.
• The warning was tied to the outlook for AI chips.

The equal magnitude of the two declines points to a sector-level repricing rather than a company-specific problem. Marvell fell on Broadcom news. That dynamic has defined the AI chip trade for two years.

What does this mean for the AI chip trade?

Broadcom and Marvell share a business model in AI. Both design application-specific chips for large cloud customers. Both supply the networking fabric that connects accelerator clusters. Their fortunes rise and fall with hyperscale capital budgets.

Tan's warning lands at a sensitive moment for that model. Investors have rewarded the two stocks on the assumption that AI infrastructure spending compounds without a spike in required investment. A chief executive flagging capital costs challenges that assumption at the source.

The 4% declines remain modest against the sector's multi-year run. But the direction matters more than the size. A CEO with direct visibility into hyperscale order books has signaled that the cost side of the AI equation deserves scrutiny. Traders responded within a single session.

What comes next?

The market will look for confirmation or rebuttal in the next round of financial disclosures from both companies. Until then, Tan's capital warning stands as the reference point for how investors price AI chip exposure, and both Broadcom and Marvell remain hostage to any further spending signals from their largest customers.