Power Laws Are Everywhere Not Just in Venture Capital

Author:

Peter Walker

Read time:

1 minute

Published date:

July 3, 2026

The top 10 S&P 500 stocks now represent 36% of total market cap, up from 17% in 2015, with concentration even higher in many other countries.

Power laws are everywhere, not just in venture.

As recently as 2015, the top 10 stocks in the American S&P500 made up ~17% of the total market cap. Today, they represent 36%.

But the US is actually one of the least power-law nations when you measure by the concentration of the top 10 stocks. In many countries, the top 10 companies take 75% or more of the total market cap weight (in some they take the whole index).

Viewed one way, this just reinforces the common refrain from mega-fund venture capitalists who say you need to be in the right 5 companies and nothing else matters.

Viewed another, this is a dangerous overconcentration and reliance on a handful of companies, a blow to any one of whom would have disastrous consequences to equity holders across the board.

Probably both :)

Author: Peter Walker

Peter Walker runs the Insights team at Carta, focused on discovering key data and narratives across the private capital ecosystem. In a former life, he was a marketing executive for a media analytics startup and led the data visualization team at the Covid Tracking Project.