Marvell Technology rose 3.9% despite broader market weakness, lifted by Nvidia partnership momentum and an upcoming addition to the S&P 500.

What happened: Marvell Technology closed at $289.54, up 3.90%, with trading volume reaching 48.6M shares—about 38% above its three-month average. The gain was driven by premarket comments from Nvidia's CEO and a new $2 billion（約3200億円） AI chip alliance, while the broader S&P 500 fell 1.19% and the Nasdaq Composite fell 1.34%.

Why it matters: Marvell's resilience during a weak market session reflects investor confidence in its AI infrastructure business. The company reported record revenue in Q1 results, an improved Q2 outlook, and strong AI-related bookings in data-center infrastructure—suggesting the market believes its partnership with Nvidia and AI demand are real drivers of near-term growth.

What to watch: The key test ahead is whether demand for custom XPUs, optical interconnects, and scale-up networking can turn Marvell's AI bookings into sustained revenue and margin growth. The company's upcoming addition to the S&P 500 is also expected to boost index-related demand and increase visibility among large-cap investors.