Rainmaker 20 Index Q2 2026: The growing role of scarcity premiums in late-stage private markets

The Rainmaker 20 Index registered a level of 585 at the close of Q2 2026 on May 15, representing an 8.3% increase quarter-over-quarter and a 115.3% increase year-over-year. The updates reflect continued momentum in secondary market pricing.

The Rainmaker 20 Index tracks secondary market pricing trends across a curated group of 20 actively traded late-stage private companies, offering market participants a consistent reference point for observing relative pricing and broader trends in the private market.

As in prior periods, performance in Q2 2026 was shaped less by broad-based movement and more by concentrated gains among a small number of high-liquidity, high-visibility companies tied to artificial intelligence, frontier technology, and defense innovation. This is consistent with Rainmaker’s broader 2026 view that late-stage private markets are increasingly being driven by AI disruption, renewed IPO expectations, and a return of risk appetite among buyers sidelined in recent years.

At the same time, the Q2 numbers revealed increasing divergence within the AI trade itself. Investor demand for AI exposure remained intense, but investors became more selective, leaning into companies perceived to have durable technological advantages, differentiated infrastructure positioning, or meaningful scarcity value in the secondary market.

Key Themes Driving Q2 Performance

The AI Arms Race Intensifies

The defining theme of Q2 2026 was the continued acceleration of the AI ‘arms race’, with leading model developers and infrastructure players driving a strong share of Index movement.

Across the Rainmaker platform, demand for AI exposure remained elevated, but increasingly selective. The story is no longer simply “AI broadly,” but rather which companies are emerging as durable platform winners.

Anthropic, OpenAI, and other AI-native companies continued to attract strong investor demand. Anthropic, in particular, recorded a 122% quarter-over-quarter increase, making it one of the strongest performers in the Index and reinforcing its position as a leading contender in the frontier model landscape. This quarter, Anthropic became a case study in how scarcity, access, and ownership control increasingly influence valuation dynamics across late-stage private markets.

Rainmaker CEO Glen Anderson noted that Anthropic has long been among the most difficult stocks to source, with an extremely limited pool of sellers willing to part with shares. That imbalance between supply and demand, combined with Anthropic’s market position, continued to drive strong investor demand during the quarter.  

The second quarter also reinforced the growing role of scarcity premiums in late-stage private markets. In several of the Index’s highest-demand names, particularly Anthropic and SpaceX, reduced shareholder willingness to sell combined with persistent institutional demand created increasingly supply-constrained trading environments. The result is a market where access itself has become a premium asset, and the role of the secondary market in facilitating trades serves as an increasingly important component of the broader capital markets ecosystem.

At the same time, OpenAI remains central to the ecosystem. Its scale, capital base, and distribution reach continue to anchor investor confidence. However, Q2 revealed a subtle but important shift: investors are beginning to differentiate between AI leaders rather than treating the industry as a single trade. Anderson and Greg Martin, Managing Director at Rainmaker Securities, caution that this is not a winner-take-all moment just yet. But the gap in secondary market dynamics between Anthropic and OpenAI highlights a new phase in the AI cycle in which investors are moving from thematic exposure to relative positioning.

OpenAI recorded an approximately 3% decline quarter-over-quarter, even as investor conviction remained strong amid intensifying competition.

Beyond model developers, Q2 also highlighted growing investor appetite for infrastructure-oriented businesses supporting the AI ecosystem. Companies tied to compute, data infrastructure, and energy capacity continued to attract increased interest as investors recognized that the long-term AI opportunity extends beyond applications and into the systems powering them. Crusoe Energy Systems, for example, rose 40% quarter-over-quarter underscoring growing demand for AI infrastructure exposure.  

Looking ahead, the critical question is not whether AI companies will continue to appreciate, but which companies can convert technical leadership into sustained revenue growth, enterprise penetration, and ultimately public-market validation.

Defense Tech: Headlines Today, Pricing Tomorrow

While AI dominated realized performance, the defense technology sector quietly emerged as one of the most important forward-looking themes of the quarter as geopolitical tensions continued to persist.

Anduril sits at the center of that narrative. The company’s $20 billion U.S. Army enterprise contract marks a step-change in how governments engage with private-sector defense innovators. Combined with reports of a potential new funding round at a significantly higher valuation, the signal is clear: defense tech is transitioning from niche to strategic priority.

Yet notably, secondary market pricing has not fully caught up.

Anduril recorded a 10.2% quarter-over-quarter increase, reflecting growing investor interest but still lagging the sharper repricing seen across AI-native companies. This reflects a broader structural reality where private markets tend to react more slowly to geopolitical developments, as pricing is driven more by transaction flow and investor positioning than immediate headlines.

Investor interest in autonomous systems, AI-enabled surveillance, and next-generation defense infrastructure is clearly building. However, that demand has not yet translated into the kind of consistent transaction volume required to meaningfully reprice the sector.

As a result, Q2 was less about realized gains in defense tech and more about positioning ahead of what investors increasingly view as a long-term structural trend.

Liquidity Concentration and Market Leadership

A consistent structural trend that persisted through Q2 is the continued concentration of liquidity in a small number of high-profile issuers.

Companies such as SpaceX, OpenAI, Anthropic and Anduril not only command significant investor attention but also exhibit higher transactional velocity in the secondary market, reinforcing their role as bellwethers for broader late-stage private market sentiment.

SpaceX remains a clear example of this dynamic, with secondary market activity reflecting sustained demand ahead of a widely anticipated liquidity event. The company recorded a 14.2% quarter-over-quarter increase during Q2, maintaining its position as one of the most influential constituents within the Index.

According to Anderson, SpaceX has been consistently “up and to the right,” remaining resilient through multiple market cycles, contrasting with many private companies that experienced steep valuation resets between 2022 and 2024.

With IPO expectations building, the dynamic is shifting further. Rainmaker continues to see a highly active buy-side environment paired with declining willingness among existing shareholders to sell. The result is a tightening market where pricing is being driven as much by scarcity as by underlying fundamentals.

This concentration of liquidity has two key implications. First, Index performance is increasingly shaped by a relatively small number of influential companies. Second, it reinforces the role of the Rainmaker 20 Index as a signal of where liquidity is actually occurring, rather than a broad representation of all private company performance.

At the same time, Q2 reflected a relative de-emphasis on consumer fintech and crypto-adjacent names compared with frontier technology sectors such as AI, defense, and infrastructure. Companies including Revolut, Ripple, and Kraken experienced weaker quarterly performance, suggesting investor capital continues to rotate toward businesses perceived to have asymmetric exposure to next-generation technological platforms.  

Looking Ahead

As the calendar moves toward the second half of 2026, several forces are likely to shape the next phase of Index performance.

The first is the potential for a major liquidity event. SpaceX remains the most closely watched candidate, and its path toward a public listing could set a valuation benchmark for the broader private market. However, Anderson and Martin caution that an IPO of that scale could absorb a significant portion of available liquidity, potentially limiting capital available for subsequent offerings.

Second, the Anthropic versus OpenAI narrative will remain central to investor discussions. While Anthropic demonstrated extraordinary recent momentum, OpenAI’s scale and distribution advantages continue to position it as a critical long-term player.  

Third, Anduril may become a more meaningful Index driver if institutional demand for defense-tech begins to flow through secondary pricing. Increased transaction volume and deeper institutional participation could accelerate repricing across the sector.   

Finally, investors are increasingly focused on which private companies can sustain premium valuations as markets transition from narrative-driven enthusiasm toward more fundamentals-oriented positioning. Companies capable of converting technological leadership into durable revenue growth and public-market readiness are likely to command an outsized share of liquidity and investor attention heading into 2027.

Over the longer term, these dynamics point toward a private market that is becoming more transparent, more liquid, and more differentiated, with clear leaders emerging across AI, space, defense, and frontier infrastructure.

Conclusion

The Rainmaker 20 Index continues to serve as a focused lens into private market performance, capturing where capital is flowing, how valuations are evolving, and which companies are defining the next phase of private market growth.

As the market moves into the second half of 2026, the key question is not whether momentum will continue, but how it will be distributed—and which companies will ultimately define the next generation of market leadership.