Elon Musk's dream merger is a nightmare for SpaceX shareholders

The big SpaceX story on its Q3 call wasn’t the blowout quarter itself. It was Elon Musk saying SpaceX and Tesla are now weighing a merger, with each company having set up special committees of independent directors to look at it. Musk can’t sit on those committees because he’s a conflicted party, but he clearly likes the idea, and the market seemed to like it too: Tesla rose 3.4% the next day and SpaceX jumped 7.8%, adding $155 billion in value.

At first glance, the match-up looks natural. SpaceX already buys Tesla Megapack batteries and Cybertrucks, Tesla put $2 billion into xAI, which SpaceX bought in February, and both companies share ownership of Terafab. Musk has long talked about building one giant AI-driven empire, and this would move him closer to that. The trouble is that the financial case starts to wobble fast.

The core problem is what SpaceX would have to give up for Tesla. If a deal carried a 30% premium, Tesla would cost about $1.98 trillion. Against SpaceX’s own $2.14 trillion valuation, that would mean issuing stock equal to 92% of SpaceX’s current shares outstanding, pushing the share count from 13.1 billion to 25 billion. SpaceX would be handing over almost half its future earnings for a company that posted $3.28 billion in GAAP net profit over the last four quarters, while SpaceX itself had a $1.5 billion loss over that stretch. Right now, the deal would barely move SpaceX from slightly negative earnings per share to slightly positive ones.

And that’s before the timing problem kicks in. SpaceX’s own profits are improving quickly, while Tesla’s are fading. SpaceX posted $4.4 billion in GAAP net profit in Q3 alone, reversing three straight quarters of deficits. Tesla’s profits, by contrast, have fallen from $15 billion in 2023 and $5 billion in 2024 to a much weaker run rate now. So SpaceX would be buying low-growth earnings at a huge price and surrendering rising ones to do it.

The cash math is ugly too. In the first nine months of this year, SpaceX generated $13.1 billion from operations but spent $48.1 billion on capex, including $40 billion on AI projects, for negative free cash flow of $15 billion. CFO Bret Johnson said Q4 investment alone could run $35 billion to $50 billion, and SpaceX is trying to raise another $40 billion in debt. Tesla is no rescue here. It posted negative free cash flow of $1.1 billion in Q3 and Musk says it plans $25 billion of capex this year. Put the two together and you don’t get a cash machine. You get two cash-hungry companies trying to gulp down the same fire hose.

The punchline is simple. A merger would mostly help Tesla shareholders, who are sitting on a stock price that’s hard to justify on the basics. SpaceX holders would be the ones paying for the privilege of making that problem someone else’s.