Nasdaq Composite Outperforms Through First Half, as AI Infrastructure Stocks Power Gains

The Nasdaq Composite is pushing ahead in the final trading session of H1, adding 1.13% to 26,111.89 today to sit 12.4% up YTD. The artificial intelligence infrastructure plays and index inclusion flows are driving some of the big movers, as the tech index puts up a powerful rally into the end of the first half.

The day’s action underscored the increasingly narrow leadership propelling the tech-heavy index to a significant outperformance on the broader S&P 500 (+9.1%), or the Dow Jones Industrial Average (+8%). The smaller cap Russell 2000 index however has outperformed even further, up 20% since the turn of the year to more than double some of it’s bigger named peers.

Leaders and Laggards Today

Nebius Group surged 10.14% to $287.64, building on a staggering 395% twelve-month advance. Fellow AI infrastructure beneficiary Astera Labs jumped 8.45% to $494.48, while Marvell Technology gained 7.27% to $297.94.

Intel shares have added 6.60% to $140.42, capping a remarkable 485% one-year run as markets reassessed the chipmaker’s turnaround prospects.

Looking to the other side of the green/red divide, and enterprise software names once again bore the brunt of rotational selling, with Intuit declining 2.63% to $259.40 and Workday falling 2.86% to $120.05. PayPal dropped 4.44% to $42.41, extending a painful twelve-month slide of more than 42%.

The rally’s primary catalyst centers on structural demand for AI data center infrastructure and the mechanical buying pressure from major index rebalancing events.

Nasdaq announced earlier this month that both Nebius and Astera Labs would join the Nasdaq-100 Index effective June 22, 2026, alongside CoreWeave, Rocket Lab, and Teradyne. The inclusion forces passive indexers and exchange-traded products tracking the benchmark to purchase shares, creating sustained upward pressure.

Marvell Technology received an even more significant boost from its addition to the S&P 500, also effective June 22. The semiconductor designer has emerged as a central player in AI networking infrastructure following a March 31 strategic partnership with Nvidia that included a $2 billion investment and collaboration on NVLink Fusion and silicon-photonics-based interconnects. Marvell completed its acquisition of Celestial AI on February 2, further strengthening its optical interconnect capabilities for AI workloads.

Axon Enterprise, up 7.71% to $549.95, showed signs of recovery after a difficult stretch. The law enforcement technology provider reported first-quarter revenue of $807 million on May 6, representing 34% year-over-year growth driven by cloud-based software and sensor adoption. The strong print has gradually rehabilitated sentiment after the stock fell as much as 46% over the prior twelve months.

Outlook

The divergence between winners and losers highlights a fundamental tension in the current market structure. A handful of AI infrastructure names and index inclusion beneficiaries are generating outsized returns, while traditional software-as-a-service companies, fintech platforms, and defensive technology sectors struggle to attract capital.

The underperformance of enterprise software stalwarts like Intuit, down 67% over twelve months, and Workday signals markets’ scepticism about how quickly these companies can monetize AI capabilities or whether their mature franchises justify premium valuations in a higher-rate environment. PayPal’s 42% twelve-month decline reflects persistent concerns about competitive pressure from Apple Pay, Stripe, and other digital wallet providers, with limited clear pathways to capture AI-driven upside.

The mechanical nature of index-related buying provides near-term support for newly added constituents, but history suggests the boost often fades once rebalancing completes and passive flows normalize. For Nebius and Astera Labs, the test will come in subsequent quarters as markets assess whether fundamental growth trajectories justify the valuations reached during the inclusion-driven rally.