EVERY THREE MONTHS, a small committee meets in Manhattan to make decisions that dictate where billions of retirement dollars flow. You won’t see them on financial television. They belong to the Index Committee at S&P Dow Jones Indices.
Nearly all readers here likely know the S&P 500 isn’t a mindless tally of America’s 500 largest businesses. Yet in an era dominated by mega-cap hype, it is worth remembering just how ruthlessly disciplined that curated roster really is. As financial planner and podcaster Tyler Gardner pointed out in a recent episode of Your Money Guide on the Side, the index behaves less like a passive benchmark and more like a remarkably disciplined money manager that avoids the behavioral flaws that plague everyday investors.
To enter the index, sheer market capitalization is not enough. A candidate must report positive cumulative earnings over its four most recent quarters under standard GAAP accounting, including its latest quarter.
When Wall Street gets euphoric, it invents bespoke metrics to justify astronomical valuations, and rival benchmarks regularly rewrite their eligibility rules to capture hot initial public offerings on day one.
Gardner highlighted this dynamic with the recent SpaceX initial public offering. Living here in Austin, just up the road from their massive operations in Bastrop and South Texas, the atmosphere was electric. I watched employees and early insiders snap up multimillion-dollar homes across town purely in anticipation of cashing out their equity packages. I imagine private artificial intelligence giants will prompt similar real estate booms in the not-too-distant future (can it get any more expensive in Silicon Valley?).
Yet when advisers pushed for immediate inclusion into major equity benchmarks, the S&P committee refused to budge. While other index providers accommodated the debut by bending float and seasoning requirements, the S&P committee simply pointed to its rulebook: come back when you have four consecutive quarters of audited GAAP profitability and a sufficient public float.
Could the index miss out on huge early gains in SpaceX, Anthropic, or OpenAI? For sure. But missing the initial pop is a small price to pay for peace of mind.
Investors are notoriously bad at cutting losers. We fall in love with our holdings, convince ourselves a dying company is a turnaround play, and refuse to sell because doing so makes the loss official.
The index carries no such ego. As a struggling business deteriorates, its valuation shrinks, reducing its weight in the portfolio with zero human intervention and no tax hit. If it falls far enough, the committee quietly shows it the door, replacing it with an ascending company.
Equally vital is how the index handles failure. I am willing to give up sizeable potential upside in the very short term for a reasonable guarantee against negative outcomes stemming from fraud, business failure, and other corporate landmines. That will apply to the AI losers too, if they ever even make the index in the first place, and we will be left with the winners once they qualify. All that is required of us is the discipline to leave the machinery alone, and perhaps a little gratitude for that small committee that meets in Manhattan wouldn’t hurt either.
According to the Business section of today’s NYTimes,so far this year (as of 4 Oct 2026) hedge funds have borrowed $3.7T from banks with a large portion of this used to bet in the stock market. Is this a cause of overvaluation?
Great article, John. I have complete confidence in the S&P 500 for many reasons, one is what is defined above the other is a guy named Warren Buffet. My portfolio favors S&P at about 60%, and total of 85% total equities to insure to keep up with inflation and beat it over the long term. The other 15% is cash to tide me over the negative years. I won’t become a billionaire but that is just fine with me. I am now 80 years old and this is working well for me.
Let me echo the praise of the others. Good article and thank you!
Great article John! Good to know there is a ‘cop on the beat’ making sure that the S&P index does not become 10 percent ‘vaporware’.
With regards to employment and housing booms next to data centers, I don’t see it happening. Most of the jobs created will be on the front-end, during construction.
I had the opportunity to tour a data center a few years ago when I worked for a Tier 1 Telecommunications provider… the daily operations staff for a Data Center is only a handful of security people and a handful of roving IT folks walking the floor of the ‘server farm’ to take logs and swap out a bad ‘blade’ server when directed.