---
title: "Why Saudi Aramco Isn't a Proxy for SpaceX"
description: "Saudi Aramco's tiny float and state control make it a poor comparison for upcoming mega-IPOs like SpaceX, OpenAI \u0026 Anthropic."
categories: ["IPOs","public markets","finance"]
keywords: ["Saudi Aramco","Alibaba","SoftBank Corp","SpaceX IPO","IPO float","market cap"]
ai_summary: "Aramco's frozen float and state-managed valuation make it the exception, not the model, for mega-IPOs."
date: 2026-02-25
lastmod: 2026-07-23
canonical_url: https://www.tomtunguz.com/largest-ipos-market-cap-and-float/
author: "Tomasz Tunguz"
---


After writing about the [SpaceX, OpenAI & Anthropic IPO liquidity problem](/spacex-openai-anthropic-ipo-2026/), readers asked : what about Saudi Aramco? At $29.4b raised & a $1.7t market cap, it's the largest IPO in history. Doesn't it prove mega-IPOs can work?

Aramco isn't a good proxy. The next biggest example, Alibaba at $231b, is a better parallel.

| Company | IPO Year | Market Cap at IPO | Market Cap Now | Float at IPO | Float Now |
|---------|----------|-------------------|----------------|--------------|-----------|
| Saudi Aramco | 2019 | $1.7t | $1.66t | 1.5% | 2.4% |
| Alibaba | 2014 | $231b | $365b | 15% | 86% |
| SoftBank Corp | 2018 | $70b | $66b | 33% | 60% |

In 2019, Aramco floated 1.5% of the company. Six years later, it's still just 2.4%. The Saudi government holds 81% directly; the sovereign wealth fund holds another 16%. The IPO served strategic goals beyond capital markets.

Contrast Alibaba & SoftBank. Both started with real floats & expanded as founders & early investors exited. Alibaba's float grew from 15% to 86%. SoftBank's nearly doubled.

{{< email_image src="kcwxqcbwf7vqxiuy4k6q" alt="Alibaba & SoftBank Corp float percentage over time" width="540" height="304" >}}

Float expansion is only half the story. The other half is timing. When do those shares actually hit the market? The typical IPO has a 180-day lockup, a period when insiders cannot sell shares.

{{< email_image src="ctnnjx8r1sbzfowxfz9i" alt="Alibaba stock price with lockup expiration dates marked" width="540" height="304" >}}

The September 2015 unlock released 5x more shares than the IPO itself. The stock fell 52% from its $120 peak to $58, below the IPO price.

SpaceX, OpenAI & Anthropic may face less pressure. All three have run regular tender offers for years, allowing employees & early investors to sell before any IPO. SpaceX runs tenders 2-3x per year. OpenAI completed a $10.3b secondary sale in 2025. Anthropic launched its first tender in early 2025 at $350b. Much of the pent-up selling has already occurred.

But even Alibaba at $231b was a fifth to a tenth the size of SpaceX's target. The market has never absorbed a trillion-dollar IPO where liquidity was the goal.