SpaceX is an investment I’ve wanted in my Stock and Shares ISA for almost eight years. I know this because that’s how long ago a certain book — The Space Barons: Elon Musk, Jeff Bezos, and the Quest to Colonize the Cosmos by Christian Davenport — was published.

This details how visionary entrepreneurs such as Musk were bringing a Silicon Valley start-up mentality to the space industry to dramatically reduce the cost of accessing ‘the final frontier’.

After reading this (and other material), I was convinced that space would become a massive market. But disruptor-in-chief SpaceX unfortunately remained a private firm.

This summer though, the rocket pioneer is expected to go public with a blockbuster IPO. So is this finally the chance to invest inside my Stocks and Shares ISA?

SpaceX has totally transformed the rocket launch market in a few ways. For a start, it builds almost everything in-house to avoid the middleman mark-up common in the aerospace supply chain. This has dramatically lowered costs and broke the decades-long monopoly held by government agencies and legacy defence contractors.

SpaceX also has a culture of ‘fail fast, learn faster’, allowing for rapid iteration. Game-changing innovations including self-landing rockets and Musk’s vision to colonise Mars attract top talent to the company.

In 2025, the firm launched its Falcon 9 rocket 165 times, roughly one mission every 2.2 days on average! For context, emerging rival Rocket Lab carried out 21, while China succeeded with 90 orbital launches.

SpaceX reportedly generated $16bn in revenue last year, with EBITDA of $8bn. And most of its growth is being driven by Starlink, its broadband-from-space service powered by more than 10,000 active satellites.

Who’s using Starlink? Well, you name it. Airlines, cruise ships, trainlines, telecoms, military vessels, people in camper vans, remote villages, scientists in Antarctica.

Now, while I’m still very bullish, I do have valuation concerns. Because SpaceX is reportedly looking to attract a $1.75trn valuation (or potentially higher).

The price-to-earnings (P/E) ratio probably isn’t the best metric to use to value this enterprise yet. But this IPO could potentially put the price-to-sales (P/S) multiple above 100.

Beyond the extreme valuation, another thing I’m not sure about is SpaceX’s recent merger with xAI. The Grok chatbot maker is losing a ton of money and I’m yet to be convinced the two are a good fit. Perhaps the IPO prospectus will change my mind.

Thankfully, I’ve benefitted indirectly from the rocketing SpaceX valuation through Scottish Mortgage Investment Trust (LSE:SMT). The FTSE 100 fund has a massive SpaceX stake, which has helped its stock jump 64% in the past year.