Anthropic Is the Hottest Trade in Private Markets. SpaceX's Looming IPO Could Change Everything.

The secondary market for private technology company shares is experiencing a level of activity that Glen Anderson of Rainmaker Securities describes as unprecedented — and at the center of it is Anthropic. The company's private shares are commanding substantial premiums over book value, with demand consistently outstripping available supply as institutional investors who missed the early rounds look for exposure ahead of a likely public offering.

Why Anthropic Is the Dominant Trade

The bull case for Anthropic in secondary markets rests on a combination of technical differentiation, recent commercial momentum, and the asymmetric upside of being positioned in the AI infrastructure stack at the frontier model layer. Claude's recent enterprise wins, the company's expanded Amazon partnership, and the perception that it is the most credible alternative to OpenAI among large enterprises are all factors that have driven secondary demand.

The bears note valuation — Anthropic's implied private valuation has expanded significantly from its last formal funding round, and secondary premiums represent a further markup. At current trading levels, buyers are pricing in scenarios that require Anthropic to capture substantial AI revenue market share over the next five to seven years. That's not an implausible outcome, but it's a demanding hurdle.

OpenAI's Relative Position

Anderson's framing is notable: he describes OpenAI as "losing ground" in secondary market sentiment relative to its peak. The dynamics are partly fundamental — OpenAI's organizational restructuring, the ongoing governance uncertainty around its nonprofit conversion, and growing competition from Anthropic and Google have all created hesitation among institutional buyers. Secondary market prices for OpenAI shares have softened relative to implied public valuations, reflecting a more mixed risk-reward assessment than existed twelve months ago.

The SpaceX Wild Card

The most significant risk Anderson identifies is not competitive — it's capital allocation. A SpaceX IPO, which has been rumored for 2026-2027, would represent one of the largest public offerings in US history and would absorb institutional capital that currently has no public market home. Funds that have been using AI private market exposure as their primary growth bet would face a genuine choice between maintaining that position and participating in SpaceX's public debut. The timing is the key variable — a SpaceX IPO while AI private market sentiment is still elevated could create a synchronized reallocation that pressures Anthropic and OpenAI secondary valuations regardless of either company's underlying performance.