New Fast Tracks Account for Older Company IPOs

Editor's Note: This analysis was updated to reflect S&P's consultation results released late on June 4, 2026. 

We’ve talked before about how the U.S. initial public offering (IPO) market has been changing, with companies staying private longer. That also means most are going public as bigger, more mature, companies. 

Indexes are designed to be representative of the markets (or “beta” in finance jargon). When large companies stay private for a decade or more before going public, indexes that wait months to add them have less than a full picture of the market they track. 

Index providers are finally catching up. Fast-tracking very large IPOs is, in essence, helping indexes better represent all the public companies that matter to the economy and the stock market.

Three major index providers looking at new “fast-track” addition rules 

MSCI and CRSP/Morningstar already had fast-track rules in place. 

In 2026, three of the five major U.S. index providers proposed new fast-track processes to add very large IPOs to their indexes faster. Two were approved (Nasdaq and Russell) while late on June 4, S&P decided not to update their rules for the S&P 500. 

Table 1 shows where each index stands today and how existing MSCI and CRSP/Morningstar rules compare.

Table 1: U.S. indexes fast-track effective dates 

^{Source: Nasdaq, FTSE Russell, S&P, MSCI, CRSP. Market value estimates are as of June 3, 2026. Market-cap values are approximate and estimated using constituents of QQQ, IWB, and ITOT ETFs. CRSP value is not estimated and sourced from CRSP March 2026 reconstitution. MSCI value source.} 

Fast-tracking large additions helps investors

While indexing was never meant to be a tool to help investors guess the right entry point, merely a transparent representation of U.S.-listed companies that give investors a diversified portfolio, we wanted to ask the question: Does fast-tracking large IPOs benefit investors?

Our analysis below suggests that it does.

Thanks to the different addition rules, Russell tended to add IPOs much faster than S&P. 

In Chart 1, we show the date of S&P 1500 additions from 2010 to 2025 (horizontal axis). On the vertical axis, we plot the returns accrued since they were added to the FTSE Russell 1000. 

This includes 64 companies. On average, these stocks  outperformed the S&P 1500 by 176% during the period between their Russell inclusion and their S&P inclusion, with 70% of the companies outperforming the S&P 1500 while waiting for their S&P addition.

Chart 1: Most Russell 1000 IPO fast-track additions outperformed the S&P 1500  

Some of the names that waited a long time for S&P inclusion included:

• VEEV, which was added to the Russell 1000 in 2013 and waited over  12 years  for S&P 500 inclusion.
• WDAY, which  also waited roughly 12 years.
• TSLA, which  waited about 10 years.

Fast-track rules help companies, too

Index inclusion helps companies, too, providing a pool of long-term investors to help finance operations. But it’s also important to remember that most large IPOs will see their free float increase over time – as insider share lockups expire and owners sell, or through secondary offerings and treasury share sales. That means the companies’ index weights and index buying, at different price points for the companies’ stock, will increase over time, too.

Table 2: Potential IPOs and company ages  

The more index rules change, the more indexes stay the same

So, what's the bottom line? Index providers aren't just updating rules for the sake of it, nor is this a new phenomenon.

Arguably, the first index fund was created almost 50 years ago as a simple way to diversify and invest in “the market.”

As index investing became more popular, size, style and sector indexes were created. In the late 1990s, investors realized that market cap-weighted indexes made it difficult to buy enough shares in “privately held” companies. In the space of years, most index providers adapted by moving to free-float weightings.

Today, we see a similar trend. Index providers are all adapting to a market that looks different than it did 25 years ago — although today, the problem is that the most consequential companies arrive at the public market later, larger, and with a longer track record. 

Getting them into broad market tracking indexes faster means that the indexes better reflects the companies that matter to the economy and the market. That’s what indexes are designed to do. And the good news is, doing that seems to be good for investors, too.