Three months after SpaceX's record-breaking Nasdaq debut, Wall Street is asking whether Anthropic's own Initial Public Offering (IPO) could top it. The AI firm has filed its S-1 with the United States Securities and Exchange Commission (SEC) in confidence and plans to go public later this fall, thus providing a direct comparison to the most expensive listing in the stock market history.

SpaceX went public on June 12, priced at roughly $150, and raised $86.2 billion after the overall commitment, outshining Saudi Aramco's nearly $26 billion record in 2019.

At the end of its first day on the stock exchange, SpaceX had a market value of roughly $2.1 trillion and a price-to-sales ratio of 112 times based on 2025 revenue.

However, SpaceX offered merely 4% of its equity; therefore, the buyers pay a very high multiple for a company that generates losses due to its untested AI project.

The firm’s valuation stood at $61.5 billion in early 2025, rising to $183 billion by September, followed by an increase to $380 billion by February after a $30 billion Series G funding. In its latest move, a $65 billion Series H funding saw the firm value reach $965 billion, backed by companies such as Amazon, Micron, Samsung, and SK Hynix.

Annualised revenue tells a similarly steep story: roughly $9 billion at the end of last year, $47 billion by the May raise, and $65 billion by July, driven by enterprise use of the Claude API, Claude Code, Claude Cowork, and Claude for Financial Advisors.

Anthropic's confidential S-1 has fuelled talk of an IPO valued around $2 trillion, a figure that would put it in the same league as SpaceX by valuation alone.

Matching SpaceX on cash raised is a taller order, though, and would likely require offering a larger float than SpaceX's roughly 4% stake, a level of dilution founders and existing investors may be reluctant to accept.