SpaceX IPO: A Market Test, Not a Breaker

Rob Arnott argues SpaceX’s mega-IPO would not break capital markets but would stress them, potentially widening the valuation gap between index constituents and non-members. While index funds would absorb the stock under float-based rules, such mega-IPOs could still trigger sizable inflows and entrench the advantages of benchmark membership—leaving long-run returns more favorable for non-members if their cash-flow growth overtakes that of the giants.