Elon Musk’s biographer Walter Isaacson says the SpaceX IPO filing may be a step toward something much bigger, calling the potential listing Musk’s “biggest act” and predicting he will eventually push to fold all his companies into one.

Isaacson said that ever since Musk was a kid with very few friends, the notion of humanity becoming a multiplanetary species has been what drives him most.

SpaceX confidentially filed its S-1 with the SEC this week, putting the company on track for a potential June listing.

Reports suggest the company could seek a valuation north of $1.75 trillion and raise up to $75 billion, which would make it the largest IPO in history.

Isaacson Says The Pieces Are Coming Together

Isaacson said if Musk could put data centers in orbit and then build a base on the Moon, that would dwarf anything he has done before.

It makes sense to do it as one company, Isaacson said on CNBC Thursday morning.

Engineers already move between Musk’s ventures, and the businesses “mesh well together.”

The host agreed that this would suit investors, but asked about the key-man problem. Isaacson agreed it was a real concern.

But he talked up SpaceX President Gwynne Shotwell as someone who helps Musk execute without tamping down his drive, noting she appears to be on the command team.

What Prediction Markets Are Saying

Kalshi traders are pricing a 32% chance that a Tesla Inc ( TSLA ) and SpaceX merger is officially announced by June 30, 2027.

Dan Ives of Wedbush Securities has separately predicted a 2027 merger, calling it the “holy grail” of Musk’s AI ambitions. He maintains a $600 price target on Tesla.

Not everyone agrees. Gary Black of The Future Fund has warned a merger could mean a 20-25% dilution hit to TSLA shareholders.

On the IPO itself, Polymarket gives SpaceX a 90% chance of being the largest IPO by market cap in 2026.

Why Tesla Investors Are Watching

Tesla remains the most liquid way to trade Musk exposure. Tesla is trading around $369 today, down 3% after releasing disappointing deliveries for Q1.

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