SpaceX is finally going public — and at a valuation that's likely to make it one of the world's biggest companies the moment it hits the market. So what happens when a company worth as much as $2 trillion suddenly needs to be folded into indexes, ETFs, and portfolios built for a different era?

On this episode of Trillions, Eric Balchunas and Joel Weber are joined by Bloomberg Intelligence analysts James Seyffart and Sharoon Francis to unpack the dawn of the mega-cap IPO. They explore how index providers are rewriting decades-old rules to accommodate SpaceX, why passive funds could become some of its biggest buyers, which ETFs and mutual funds already have exposure to the company, and what it all means as other private giants — including OpenAI and Anthropic — prepare to enter the public markets.