SpaceX (SPCX) is poised to close out its first full week as a public company on a down note, with shares on track to shed 18% — extending a rough debut for one of the most highly anticipated IPOs.

The slide dragged SpaceX’s market capitalization back toward $2 trillion, down from a peak above $2.5 trillion reached in its first days of trading. At current levels, the stock is flirting with its $135 IPO price and has slipped beneath the $150 mark, where it opened — a psychologically important line, and a sign SpaceX is following other blockbuster debuts that eventually sank below their offer price.

Just yesterday SpaceX priced a $25 billion bond sale that drew nearly $90 billion in orders — demand so heavy the company upsized the deal from an initial $20 billion target. On its face, that kind of appetite is a vote of confidence, but the question for investors is why a company that just raised a fortune in its IPO needed to turn around and borrow billions more.

Now Bloomberg reports paper losses on SpaceX’s debt offering have mounted since it began trading, with losses now totaling around $305 million relative to benchmark US treasuries.

To some on Wall Street, the back-to-back capital raises look worrisome. The bearish take is that SpaceX is pulling forward every dollar it can while the window is open — and that the rush to lock in the debt marks the top of the Space/AI trade that has minted trillions in paper wealth over the past year.

Speaking at the FT Global Insurance Summit, Allianz chief investment officer Ludovic Subran said the SpaceX deal shows markets shifting “from a stretched boom into bubble territory.”

The ramifications can be seen with OpenAI (OPAI.PVT), which has reportedly tapped the brakes on its own long-anticipated IPO, a move investors are reading as confirmation that the exuberance over AI companies is cooling off as expenses rise and cash flow growth slows.

Separately, the Financial Times reported that SpaceX is weighing a move into consumer mobile, exploring a Starlink-based wireless service that would sell plans directly to consumers and pit the company against established carriers.

The plan would build on Starlink’s direct-to-cell ambitions and give SpaceX more recurring revenue, something it needs to defend its $2 trillion valuation and its ambitions for further growth.

Pras Subramanian is Lead Transportation Reporter for Yahoo Finance. You can follow him on X and on Instagram.

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