US stocks showed clear signs of divergence on Monday, with the year's best-performing names facing heavy selling while other sectors held their ground, signaling an increasingly pronounced rotation beneath the surface. According to calculations by Yahoo Finance, as of midday Monday, the top 10% of S&P 500 gainers for 2026 had fallen an average of about 1.6%, making them the worst-performing segment of the index that day. The decline was even more concentrated among leaders, with 19 of the top 20 stocks for 2026 moving lower, averaging a drop of 2.7%. SanDisk Corp (NASDAQ: SNDK), for example, remains up over 500% year-to-date, but fell more than 7% in a single session on Monday. Both Micron Technology Inc (NASDAQ: MU) and Western Digital Corp (NASDAQ: WDC), whose shares have doubled this year, dropped over 5% on the day.

The weakness was most visible in the chip sector. Last week, the iShares Semiconductor ETF (SOXX) was hit by aggressive selling after rebounding into a key technical resistance level. On Monday morning, the ETF fell to a three-week low before finding buying support near the $500 round-number level. Software stocks also came under pressure.

But the other side of the market tells a very different story. "This is a large-scale rotation," said Mark Newton, head of technical strategy at Fundstrat, on Monday. He noted that this year's market leadership has shifted from energy to technology, and now, as various segments within tech correct in turn, sectors like financials, industrials, and healthcare have stepped up to take the baton. The trend is becoming increasingly clear. On Monday, among the major S&P 500 sectors, technology (XLK) posted the worst performance, while consumer staples (XLP), financials (XLF), and communication services (XLC) each rose 1%. Financials traded near their intraday all-time high.

This rotation has been underway for months. Healthcare began breaking out to the upside even as the chip sector entered a bear market. Less than two weeks ago, some of the riskiest trades in the market were still leading the charge. Now, those former leaders are fading, but the selling has not engulfed the entire market. On Monday morning, even as the S&P 500 edged lower, roughly 56% of its constituent stocks were trading higher. After a bull market that has lasted nearly four years, the current dynamic is vastly different from past periods of across-the-board declines. "We know that rotation is providing this market with fairly substantial breadth," Newton added.

Institutional views on the rotation are largely aligned on its persistence, but opinions differ on how to position for it. JPMorgan Chase & Co (NYSE: JPM) released a research note on Monday saying it remains constructive on equities for the rest of the year, but expects gains to come from sector rotation rather than a broad, aggressive rally. Strategist Fabio Bassi anticipates a gradual uptrend with rotation as the main theme. On positioning, JPMorgan favors quality growth names and hyperscale cloud vendors, while also viewing the semiconductor sector as attractive following the recent repricing of valuations. The firm also interpreted the steepening of the US Treasury yield curve as reflecting increased capital demand and investment opportunities, rather than concerns over policy mistakes.

Goldman Sachs struck a more cautious tone. Senior trader Natasha Tiwana warned that the momentum structure of the AI theme has fundamentally shifted, noting that within momentum factors, the semiconductor and AI complex is rotating from long to short positioning, with software taking over as the largest weight in short-term momentum. Goldman pointed out that in 2026, the number of days with momentum factor declines exceeding 5% has already surpassed the total for the past five years combined, forcing the market to seek broader diversification beyond the AI narrative. In terms of allocation, Goldman advises investors to look toward European and Japanese bank stocks, gold miners, and copper miners for hard-asset exposure. However, the firm also stated clearly that the AI trade is not over, but its composition, momentum characteristics, and margin of safety are being rewritten in real time. It recommends a more tactical approach to AI beneficiaries, focusing on opportunities where there is a significant divergence between price and earnings per share (EPS).

Looking ahead, the market is closely watching two key catalysts: NVIDIA Corp (NASDAQ: NVDA) is set to report earnings on August 26, a major quarterly test of the AI narrative, and Federal Reserve Chair Warsh is scheduled to deliver his first major speech at Jackson Hole on August 28, which could offer fresh guidance on the interest rate outlook. With both events on the horizon, the direction of US stocks is set for a pivotal definition.