SpaceX Could Disrupt Anthropic’s Private Market Momentum

The landscape for trading private company shares has transformed dramatically over the past decade and a half. Where once only a handful of institutional investors operated, thousands now actively participate in the late-stage private market. Glen Anderson, president of the investment bank Rainmaker Securities, has witnessed this evolution from the front lines. His firm facilitates transactions in about a thousand private stocks, giving him a clear view of the major forces currently shaping the secondary market. According to Anderson, the current narrative revolves around three dominant players: Anthropic, OpenAI, and SpaceX, with a storyline far more nuanced than simple headlines suggest.

Demand for shares in AI firm Anthropic has become exceptionally intense, bordering on insatiable. Anderson confirms that it is currently the most difficult stock to source in his marketplace, with a severe shortage of sellers. This surge was partly ignited by the company’s very public stance against the Department of Defense, an event that initially seemed risky but ultimately rallied public and investor support. That episode helped differentiate Anthropic from OpenAI in the eyes of the market, amplifying its appeal. While many institutional investors still seek exposure to both leading AI companies, the momentum in private trading has demonstrably shifted toward Anthropic.

This does not imply OpenAI has collapsed. Anderson resists a binary interpretation, but acknowledges the trading activity for its shares is not nearly as vibrant. On valuation, secondary market transactions suggest a company worth around $765 billion, a noticeable discount to its latest primary funding round valuation of $852 billion. OpenAI has moved to assert more control over its secondary market, warning investors to be cautious of unauthorized brokers and establishing fee-free channels through major banks. Notably, some banks are now offering OpenAI shares without their typical carry fees, while still charging them for access to Anthropic.

The wildcard in this dynamic is SpaceX. Anderson describes it as a rare standout that largely avoided the severe valuation corrections that punished much of the private market from 2022 to 2024. The company’s share price trajectory has been consistently positive, a trend Anderson attributes to management’s disciplined approach to pricing in funding rounds, avoiding the temptation to maximize valuation at every turn. This conservative strategy has generated enormous returns for early investors. A stake purchased during a $12 billion valuation round in 2015 would now represent a gain of over 100 times, with the company valued above $1 trillion.

SpaceX’s recently confidential filing for an initial public offering is poised to be a historic market event, potentially raising between $50 billion and $75 billion. This impending debut is already reshaping its private market, sparking a flood of buy-side interest as supply from existing shareholders dwindles in anticipation of the public listing. This creates a significant challenge for both Anthropic and OpenAI, which are also reportedly eyeing public offerings this year.

The first-mover advantage in going public is substantial. Anderson bluntly states that SpaceX will soak up a tremendous amount of available liquidity, as there is only so much capital allocated for major IPOs. The company that tests the waters first accesses that capital pool, leaving those who follow to face greater scrutiny and potentially diminished investor appetite. Even for hyped AI firms, this fundamental market dynamic applies. Timing a public offering is a high-stakes gamble: move too early and you bear the risk of testing market receptivity, but wait for another to lead and you may find the largest checks have already been written.