Wall Street spent May watching Micron Technology Inc. (MU) rally toward a market value of roughly $850 billion on the strength of artificial intelligence memory demand. Micron's 46% monthly gain is nothing to sneeze at—unless you're looking at the small-cap world.

Below the headlines, a quieter move was underway. The seven best-performing stocks in the Russell 2000 each more than doubled Micron's return in a single month. Some tripled it.

The May Small-Cap Leaderboard

The table below ranks the seven Russell 2000 names by month-to-date performance.

What Actually Drove Each Move?

Each of the seven rallies had a specific trigger, and most of them landed in the first two weeks of May. Here is the catalyst behind each name.

• Hyliion Holdings Corp.: Two catalysts, two legs. Hyliion reported on May 12 with revenue up 479% year over year and a narrower net loss, and the stock jumped roughly 30% on the print as the company confirmed it had cleared UL certification testing for its KARNO Power Module. The second leg came late in the month: the U.S. Navy selected the KARNO platform for power trials on the unmanned USX-1 Defiant vessel, and the stock surged another 40% in the days that followed, trading near $6. An earnings pop, then a defense headline on top.
• agilon health, inc.: The senior-care company reported stronger first-quarter profitability and raised its full-year 2026 sales guidance, a combination that reversed a long stretch of weak sentiment. The stock gapped up 117.8% the next session, opening near $44 and closing above $60. It did not stop there. Shares climbed for most of the rest of the month, reaching the mid-$80s. Deutsche Bank upgraded the stock to Buy from Hold during the month.
• Rackspace Technology, Inc.: Rackspace reported on May 6, and the stock posted back-to-back daily gains near 55% in each of the two sessions that followed, lifted by a swing to first-quarter profit and a multi-year AI infrastructure partnership with Advanced Micro Devices, Inc. (AMD) announced on May 7. With roughly 21% of its float sold short heading into the news, the move was amplified by short covering. Shares ran from roughly $2.50 to above $7.50 in days. The retracement was just as sharp: by late May the stock had fallen back near $4.
• Entravision Communications Corporation: The media and ad-tech company reported first-quarter results on May 5 showing revenue up 114% year over year to about $197 million and a return to profitability. The gain was driven by its Advertising Technology and Services segment, where revenue rose 204%. Management also pointed to the 2026 political advertising cycle as a coming tailwind. Shares rallied 94% in the post-earnings session and continued to drift higher thereafter.
• NextNRG, Inc.: The AI-driven energy and mobile-fueling company reported that April 2026 was the highest single revenue month in its history, with monthly revenue of roughly $21 million. The move is best read as a sharp rebound: the stock remains down about 41% year to date, and its financing leans on convertible notes that can dilute shareholders.
• Innodata Inc.: The data-engineering supplier reported first-quarter results on May 7 with revenue up 54% year over year and lifted its full-year 2026 growth target above 40%. The stock gapped 86% higher on the print and extended through the month. Wedbush raised its price target to $100 from $80 the following week, the clearest analyst endorsement in the group.
• Ambiq Micro, Inc.: The ultra-low-power chipmaker reported first-quarter net sales up 59% year over year on May 12, with more than 80% of units shipped running AI algorithms on the device. Management guided second-quarter sales higher still.