Wall Street’s Index Plumbing Bends to the Trillion-Dollar IPO
On 1 May 2026, Nasdaq changed how its main index works, and it did so to win the biggest stock listing in history before that company had sold a single share. Under the new “fast entry” rule, a large new company can join the Nasdaq 100 just 15 trading days after going public, instead of waiting three months. SpaceX promptly chose Nasdaq over the New York Stock Exchange. The catch is that index funds tracking the Nasdaq 100 will then be forced to buy SpaceX whether or not they think it is worth the price.
For European investors, this is not a distant American story. Pension funds and savings schemes across the continent have poured money into passive funds that simply track these indices. When an exchange can engineer demand by editing its own rulebook, those funds end up buying an expensive new stock automatically, and the people whose retirement money sits inside them never get a say. That is the real issue here: the indices that millions treat as neutral and low-cost are being reshaped to suit the companies listing on them.
What Nasdaq actually changed
For years, a newly public company had to trade for at least three months before it could join the Nasdaq 100. That waiting period gave the market time to find a fair price. Nasdaq has now scrapped most of that wait for the largest companies. A big enough new listing can join the index after 15 trading days.
The rule was written with one company in mind. SpaceX is preparing the largest stock market debut ever attempted, and it told exchanges that fast index entry mattered. Nasdaq changed its rules; SpaceX chose Nasdaq. Its filing shows $18.67bn in 2025 revenue and a $4.94bn loss, with a June debut planned under the ticker SPCX. Two more giants are close behind: OpenAI and Anthropic are both laying the groundwork to go public.
Why index funds are forced to buy
An index fund’s job is to copy its index exactly. So when a new company joins the Nasdaq 100, every fund tracking it has to go out and buy the stock, no matter what it costs. More than 200 investment products holding over $600bn track the index, so that is a lot of automatic buying landing on one stock at once.
The problem is that there will not be much SpaceX stock to go round. The company is targeting a valuation of $1.75tn to over $2tn and a raise of up to $75bn, which sounds enormous but is only a small slice of the company. A flood of forced buying meeting a small supply of shares pushes the price up fast. And as the price rises, the stock’s weight in the index rises too, which forces the funds to buy even more. The effect feeds on itself.
Someone has to sell
Index funds are almost fully invested at all times. So to buy a large new stock, they have to sell something they already own to raise the cash. That means the arrival of SpaceX forces selling elsewhere in the index.
There is a second cost. The old three-month wait stopped fast-money traders from gaming the system. Now a hedge fund can buy SpaceX on day one and sell it to passive funds 15 days later at a higher price. In effect, ordinary long-term savers hand a quick profit to professional traders. That is the trade-off Nasdaq has built into the rule, and it lands on the people least able to see it coming.
The other exchanges are following
Nasdaq is not alone. More than $30tn is tied to the S&P 500, the Dow, the Nasdaq Composite and FTSE Russell, and all of them are now looking at ways to fast-track new listings too. The pattern is clear: the companies that run the world’s big indices are competing to let giant new firms in faster, and the companies listing now hold the upper hand.
The irony is that none of this is about giving people access. Anyone can buy SpaceX the moment it starts trading. The rushed inclusion exists to guarantee the company a wall of forced buyers — and to hand the risk of an unproven, expensive stock straight to the passive investor.
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