Space Exploration Technologies Corp SpaceX (SPCX) has now faced two waves of insider share unlocks since its blockbuster June initial public offering, and so far the stock has shrugged them off. But the next test is bigger, and it lands this Wednesday.

Shares closed Tuesday at $153.47, comfortably above the $135 IPO price and about 32% below the intraday peak of $225.64 hit just days after the June 12 debut.

The First Unlock: A Rally Instead of a Rout

SpaceX's first big test came on Aug. 6, when 911.5 million shares held by employees and early investors became eligible to trade. That more than doubled the company's public float, which sounds like a recipe for a supply glut.

But instead of caving, shares rallied. The stock had closed the prior session at $108.27, a fresh post-IPO low tied to an earnings report that showed capital expenditures running at more than double revenue. Then, on the day of the unlock, shares catapulted 16% higher and finished the week at $133.11. The Wall Street Journal described the move as proof that SpaceX's "true believers" were propelling shares past the lockup.

The Second Unlock: A Wobble, Not a Break

A second, smaller unlock followed on Aug. 20, when roughly 319 million additional shares came free under the staggered schedule laid out in SpaceX's prospectus. The stock wobbled but avoided a lasting slide, and by Aug. 10 shares had already closed above the IPO price for the first time in weeks, according to CNBC.

Argus Research upgraded the stock to Buy shortly after the first unlock, arguing the shares merited the call partly on CEO Elon Musk's track record running Tesla Inc. (TSLA).

Third Unlock: This Wednesday

Now comes round three, and it's a bigger one. Roughly 700 million additional shares will become eligible in September, more than double the size of the Aug. 20 release and approaching the scale of the first unlock.

CNBC pointed to Wednesday's share release as one of two remaining supply events still keeping the stock "cheap" relative to Wall Street's price targets. Oppenheimer has a $280 target on the stock, while JPMorgan sits at $240.

And there's more to come. Further tranches are scheduled for Sept. 24, Oct. 9, and Oct. 24, before the full 180-day lockup expires on Dec. 8. Musk's own stake, the largest single block, stays locked until June 2027.

So the question is whether insiders treat Wednesday's tranche as an exit ramp, or whether investors again absorb the float without flinching. The answer could shape SpaceX's next chapter as a newly public, AI-heavy rocket company.