Small caps last week: Ebola vaccine, SpaceX IPO beneficiaries, Russell rebalancing

Shares of a micro-cap vaccine developer surged following an Ebola outbreak. Bloomberg compiled a list of promising space-sector small caps ahead of the SpaceX IPO. The largest crypto ATM operator in the U.S. filed for bankruptcy, while U.S. lingerie retailer Victoria’s Secret changed its ticker symbol in an effort to win back customers. These are the top small-cap stories from May 18-22 in our weekly recap.

Vaccine developer GeoVax said its experimental vaccines could potentially combat multiple viruses, including the new strain of Ebola currently spreading in Congo and Uganda. On Saturday, May 17, the World Health Organization declared the situation an emergency. There are currently no approved vaccines targeting the circulating strain, GeoVax noted.

Following the company’s statement, its shares rose 11.5% on Wednesday and gained another roughly 20% on Thursday. Two Wall Street analysts currently rate the stock a “buy,” while one recommends “hold.” The average target price stands at $15 per share, implying upside of roughly fourfold from current levels.

With Ebola and hantavirus outbreaks again bringing vaccine stocks into focus, Oninvest columnist Roman Kutuzov looked at who might benefit.

Ahead of Elon Musk’s SpaceX IPO, Bloomberg named 13 aerospace stocks investors should watch. The upcoming offering is driving fresh investor flows into the sector, prompting Wall Street to search for the next major winner in space exploration, Bloomberg wrote.

Among Bloomberg’s top picks are satellite-data provider Planet Labs, rocket and spacecraft developer Firefly Aerospace, low-cost satellite manufacturer York Space Systems, lunar rover developer Intuitive Machines, and others. 

Oninvest editor Yulia Kotova summarized the key takeaways from the SpaceX prospectus, filed last week.

The first semiannual rebalancing of the Russell indexes – the main benchmark for U.S. small caps – will conclude at the end of June. Oninvest analyst Aldiyar Anuarbekov picked five companies that could be added to the index, along with four likely deletion candidates.

Potential additions include optoelectronics and data-center substrate producer AXT, drone-component maker Unusual Machines, and hydrogen-power pioneer FuelCell Energy. More than $11 trillion in assets are benchmarked to Russell indexes, meaning any membership changes can trigger significant capital flows from index funds and ETFs.

Bitcoin Depot, the largest crypto ATM operator in North America, initiated voluntary bankruptcy proceedings. The company said tougher regulation of crypto ATMs in the U.S., as well as effective bans in some states, undermined its business model. Earlier, Bitcoin Depot notified the U.S. Securities and Exchange Commission that it would not be able to file its first-quarter report on time. On Monday, Bitcoin Depot shares plunged more than 73%, falling into penny-stock territory.

The company was founded in 2016 and went public in 2023. Its network includes nearly 9,000 kiosks worldwide where customers could exchange cash for Bitcoin. In 2025, Bitcoin Depot announced several major deals, including the acquisition of 527 crypto ATMs operating under the National Bitcoin ATM brand in the U.S. But since the start of this year, the company has faced a string of setbacks. First came high-profile lawsuits alleging facilitation of crypto fraud. Then Connecticut suspended the company’s license, followed by a cyberattack in which hackers stole about $3.7 million from customer crypto wallets.

Victoria’s Secret shares will begin trading on the NYSE under the new ticker symbol VSXY starting June 2. The company said the change reflects a new chapter in the brand’s evolution and a return to the idea that “sexy has always been part of our DNA.”

According to Bloomberg, under CEO Hillary Super the retailer is attempting to regain market share by returning to the idea that “sex sells” and refocusing on its core bra category and the youth-oriented PINK brand. Markets were reacting positively to the news: on Thursday, Victoria’s Secret shares rose nearly 6%.