All Eyes Are on SpaceX's Next Share Unlock on Sept. 9. But These 3 Unstoppable Growth Stocks Are Better Buys Hiding in Plain Sight.

Space Exploration Technologies (NASDAQ: SPCX) has given investors plenty to get excited about this year. The company's IPO was all the rage this summer, as tech pundits and analysts weighed its impact on the market. But for retail investors, SpaceX has a problem that has little to do with rockets: Its various stakeholders can't sell most of the shares they own -- yet.

When companies go public, their pre-IPO stakeholders -- employees, executives, and other early investors -- can't start selling their shares immediately. Lockup periods are put in place to prevent too many shares from flooding the market in too short a time frame. SpaceX laid out a staggered schedule for the release of those shares over the next year, and the next release date falls on Sept. 9.

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As of that day, those early shareholders will be able to sell another 319 million shares. That does not mean every shareholder will sell their newly eligible shares. But it does create a potential technical headwind for a stock that entered the public market with a small effective float. SpaceX's own filing also registered shares held by current and former employees for potential resale, meaning investors have to think about supply as well as demand.

That is one reason I'd rather look for opportunities elsewhere in the space and technology markets today. Three companies stand out because their growth stories are tied to infrastructure that still has to be built.

1. Rocket Lab is building the other end of the launch market

Rocket Lab (NASDAQ: RKLB) is not trying to replicate SpaceX one-for-one. Its smaller-payload Electron rocket has given the company launch experience, while its larger Neutron vehicle addresses the medium-lift market. Rocket Lab has said Neutron is intended to support constellation deployments, and it already has dedicated launches booked.

The technical opportunity for the company is bigger than selling launches. Rocket Lab is building itself into an end-to-end space company, with launch vehicles, spacecraft, and components under one roof. That vertical integration can matter because satellite operators don't just need a ride to orbit. They need spacecraft, propulsion, power systems, and the ability to replace aging satellites or expand satellite constellations over time.