While the benchmark S&P 500 index is overall almost 8% in the green in 2026 and close to its all-time highs (ATH), there has been significant divergence between the performance of the various stocks contained within.
For example, one of America’s largest companies, Microsoft (NASDAQ: MSFT), remains deeply in the red even after the April rally, and Nvidia (NASDAQ: NVDA) – a top performer ever since the artificial intelligence (AI) boom started with the original public release of ChatGPT – has been underperforming its own sector.

Indeed, the difference in the performance is also evident across industries, with, for example, all semiconductor companies and all oil giants trading in the green year-to-date (YTD), and none of the major medical devices firms or advertising companies evading a fall.
Additionally, the extremes seen when comparing the various elements of the S&P 500 have translated to multiple extreme rallies in 2026, and Finbold examined the benchmark to reveal the absolute biggest winners YTD.
Seagate Technology Holdings (NASDAQ: STX)
With multiple surveys hinting that there are few, if any, benefits to adopting AI as a company and most data center projects getting either delayed or cancelled, storage availability has become the driving narrative of the bull market in 2026.
Under the circumstances, Seagate (NASDAQ: STX) – an American company focused on data storage – has become one of the strongest stocks in the benchmark S&P 500 despite being relatively underdiscussed compared to its peers.
Indeed, STX shares rallied 183.53% in 2026 and are, at press time on May 8, changing hands at $780.83.

Intel (NASDAQ: INTC)
Thanks to internal reorganization, backing from President Donald Trump and the federal government, and the continued importance of semiconductor makers for the development of AI, Intel (NASDAQ: INTC) has reversed its fortunes and become the second-best S&P 500 stock of 2026.
Indeed, after falling nearly 70% between 2021 and mid-2025, INTC stock took an upward trajectory and, having risen 209.20% YTD to $114.09, not only reclaimed its ATH set during the Dot-com bubble, but significantly surpassed it.

SanDisk (NASDAQ: SNDK)
Though its current tenure in the stock market has been relatively short – SanDisk (NASDAQ: SNDK) was split from Western Digital (NASDAQ: WDC) in early 2025 – SNDK has quickly risen to become one of the most impressive major American stocks.
Specifically, as part of the AI memory demand frenzy, the equity soared 498.64% to $1,427.10 in 2026.

Upon zooming out, SanDisk stock’s rally turns even more impressive – albeit, while also highlighting the questions surrounding the sustainability of the rise. Indeed, in the last 12 months, SNDK shares are up 3,792.80%.
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