I'm trying to understand the role of the initial IPO investors of a SPAC. From the Beginner's Guide of r/SPACs:
When the IPO occurs, a SPAC generally offers Units – generally at \$10 per Unit. These Units are comprised of one share of common stock (Share) and a Warrant (or portion of a warrant) to purchase common stock (generally exercisable at $11.50).
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In the weeks after the IPO, the common stock (Shares) and Warrants included in SPAC Units become separable. At that point, the Warrants and Shares trade separately alongside the unseparated Units.
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[SPAC] Companies will typically have a \$10 floor on their share price, as that is what must be paid out to holders of shares if the company does not successfully reach a deal.
The IPO investors could just sell their common shares for at least $10 right after the IPO (often much higher as we have seen recently) and are left with the warrant. This is essentially an opportunity for free money without any risks or downsides, apart from cash being locked up before before the common shares are traded publicly. For sure such an arbitrage opportunity cannot exist, so what am I missing here?