Not Space. Not Starlink. Here's My Top Reason to Buy SpaceX Stock.

Space Exploration Technologies (NASDAQ: SPCX), better known as SpaceX, is primarily known for one thing: launching rockets to put payloads into space, and then landing those rockets back on Earth in a condition that allows them to be reused. While this is incredible and noteworthy technology, it may not be the best reason to invest in the stock.

Another popular product from SpaceX is the Starlink broadband service, which can provide satellite-based internet to users practically anywhere on Earth. While this is also an innovative product, I still think there's a better reason to invest in SpaceX: its super intelligence (SI) division.

SI is the division that holds SpaceX's AI data center platform, and after the growth it just reported, I think it's clear that it is the top reason to invest in SpaceX stock right now.

Image source: Getty Images.

Super intelligence's revenue growth rate is just absurd

SI was formed from xAI, another one of Elon Musk's start-ups that SpaceX acquired a few months before going public. It also includes X, the social media platform formerly known as Twitter. However, X accounts for just a fraction of the SI division's total revenue, which reached $7.56 billion in revenue during the third quarter, or about 830% year-over-year growth. That's not a typo; SI's top line grew from $813 million in Q3 2025 to $7.56 billion in Q3 2026. That was also about three times as much as the $2.56 billion in revenue it brought in during 2026's second quarter.

The reality is that AI services are starting to really take off, and that the Grok family of large language models and products (like Grok Bots) is starting to become widely deployed in businesses and personal lives. That has led to huge growth for SpaceX, and it sees more growth ahead. During Q3, it invested $16.4 billion in capital expenditures in its SI division, clearly signaling that it believes in the future of this segment.

Additionally, SI posted a small operating profit of $431 million. However, one item to note is that this was the first report since the company acquired Cursor in August. That deal added to SI's revenue stream. While SpaceX didn't reveal how much of its revenue came from this acquisition, it did note that there was a sizable $1.2 billion stock-based compensation cost associated with its SI divisions due to the acquisition. This won't repeat in the future, and could push SI's profitability to far higher levels.

If the SI division can continue growing rapidly over the next few years, SpaceX may be better off renaming itself xAI, although that won't happen. This is the most exciting division for SpaceX, and investors would be better off viewing the investment through an AI lens rather than a space one.

Keithen Drury has no position in any of the stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy.