Six billion dollars, ten months after the launch announcement
xAI announced on May 26, 2024 that it had raised $6 billion in a Series B round, at a valuation reported as $18 billion pre-money and $24 billion post-money. The round was led by Valor Equity Partners and Vy Capital, with Andreessen Horowitz, Sequoia Capital, Fidelity Management & Research Company, and Saudi Prince Alwaleed bin Talal's Kingdom Holding also participating. TechCrunch had reported the $6 billion target and the $18 billion pre-money figure a month earlier, so the announcement confirmed numbers that were already circulating rather than surprising the market. [1][2]
The timing sits about ten months after Elon Musk announced xAI's founding in July 2023, and about seven months after the company shipped its first Grok release. Grok-1.5, an updated model with a longer context window, had come out the previous month. [2]
What the money was actually for
xAI's own announcement described the funds as going toward taking its first products to market, building advanced infrastructure, and accelerating research and development, without breaking that down further or disclosing revenue. [1]
Atlas interpretation: "Advanced infrastructure" turned out to mean compute at a scale most labs would need a cloud contract to reach rather than a warehouse. Four months after the round closed, xAI brought online Colossus, a cluster of 100,000 Nvidia H100 GPUs in Memphis, built in 122 days after the site was picked that June. Musk described the goal as training Grok-3 into what he called the most powerful AI in the world by the end of 2024. Whether that specific claim held up is a separate question; what the timing shows is that the Series B money and the compute buildout were the same plan executed in sequence, not two unrelated events that happened to be close together. [3]
Where it landed among that month's other checks
At the time of the announcement, Crunchbase News placed xAI as the second most valuable generative AI startup globally at $24 billion, behind OpenAI's roughly $86 billion valuation from an earlier tender offer and ahead of Anthropic's reported $18 billion. Mistral AI closed its own round, a $600 million raise valuing it at $6 billion, in the same window, a fraction of xAI's number despite Mistral already shipping a competitive open-weight model. [4]
Atlas interpretation: A company ten months old, with one released model and no disclosed revenue, out-valued at $24 billion by only OpenAI is less a statement about Grok's technical standing in May 2024 than about what investors were pricing: Musk's ability to raise capital and stand up infrastructure fast, and the assumption that being second to a moving target was still worth a premium over almost everyone else in the field. [4]
The valuation kept moving after this
Less than a year later, in March 2025, xAI acquired X in an all-stock deal that valued xAI itself at $80 billion, more than three times the Series B figure. In February 2026, SpaceX acquired xAI outright, with contemporary reporting valuing the combined entity at roughly $1.25 trillion, though neither company disclosed a transaction price or structure for that deal. [5][6]
Atlas interpretation: Read against that sequence, the Series B looks less like a ceiling and more like the round that proved the model worked: raise on the strength of a fast-moving team and a stated infrastructure plan, spend it visibly and quickly on hardware that generates headlines of its own, and let the next valuation reset off the last one before a full product cycle has even finished. Whether that pattern reflects durable value or a market that kept extending credit to the same person's momentum is not something this round settles either way. [5][6]
Sources
- Series B funding round
xAI · May 26, 2024
- Elon Musk's xAI raises $6B from Valor, a16z and Sequoia
TechCrunch · May 26, 2024
- Elon Musk's just fired up 'Colossus'—the world's largest Nvidia GPU cluster used to train Grok
Fortune · Sep 3, 2024
- xAI Makes It Official — Raises $6B At $24B Valuation
Crunchbase News · May 28, 2024
- Elon Musk says xAI has acquired X in deal that values social media site at $33 billion
CNBC · Mar 28, 2025
- Musk's xAI, SpaceX combo is the biggest merger of all time, valued at $1.25 trillion
CNBC · Feb 3, 2026