Visualizing A Decade Of Private-Market Buildup

Editor’s note: This article is part of a series looking at how the venture and startup landscape has evolved over the past 10 years. Read more articles about seed funding, Series B trends and the rise of megafunds over the decade.

Over the past decade, Crunchbase has chronicled the rise of unicorn companies — private startups valued at $1 billion or more — as a signal of where venture capital dollars and market enthusiasm flow.

What began as a trickle in the early 2010s surged into a flood in 2021, as valuations skyrocketed and new unicorns joined The Crunchbase Unicorn Board at a record pace, with new unicorn creation growing threefold year over year.

But while the number of unicorns has continued to climb, exits have not kept pace. Today, the board hosts more than 1,500 companies, collectively valued at $6 trillion — most of which have not raised at a disclosed valuation in over three years. The board has continued to grow across all metrics, albeit at a slower pace.

Below, we visualize the vast backlog of still-private giant startups, highlighting how the private market boom has evolved into an overhang of capital, value and expectation. To gain some insight on the massive expansion of the board in 2021, we separated out cohorts from 2020 and earlier, the COVID growth years of 2021 which bled into 2022, and the slowdown of the past 2.5 years, even as AI has gained.

2020 and earlier cohorts

The 2020 and earlier cohorts have the highest exit proportion and currently also represent the majority of the board’s value, an analysis shows.

This is not surprising as these companies have had more time to grow their business and make exits. They also benefited from the boom year of 2021, when a record stream of companies went public. Of the 953 companies that joined the unicorn board before 2021, 46% have since exited, with the majority — by a factor of three —as public debuts vs. M&A exits.

Remaining on the board are some 470-plus still-private companies from this era, which account for more than half of the board’s current value at $3.2 trillion. These companies, which have had a longer time to grow, make up many of the most highly valued companies on the board and include SpaceX, OpenAI, ByteDance, Shein, Stripe and Databricks. The youngest of these valued above $60 billion is GenAI giant OpenAI, which will be a decade old by the end of this year, while the oldest is 25-year-old space exploration company SpaceX.

Rapid rise in 2021

The 2021 and 2022 cohort of new unicorns account for 54% of the companies currently on the board, and showed a massive increase in companies that joined in a short period of time. These 854 still-private companies are collectively valued at $2 trillion — a third of the current board’s value with nine of the top 50 valued companies. The most highly valued is Anthropic, part of the 2022 cohort of new unicorns and currently valued at $61.5 billion.

Slowed since 2023

In 2023 and through May 2025, 257 unicorn companies have joined the board, adding a half-trillion in value. The most valuable of this cohort are AI labs xAI, valued at $50 billion, and Safe Superintelligence at $32 billion. Many of the 2023 through May 2025 cohort of companies experienced an increase in value due to the AI wave.

Companies that have joined the board since 2023 match annual counts of earlier years, 2015 through 2017 — with around 100-plus companies per annum.

Unicorn overhang

The Crunchbase Unicorn Board is close to reaching 1,600 companies, approaching $6 trillion in value, with $1 trillion in funding raised. Only a small count of companies have dropped off the board through a lowered valuation or closure — around 40 since 2022.

And as of June 2025, over 60% of companies on the board have not raised funding with a disclosed value in more than three years.

While funds have downgraded valuations internally, they are still looking for returns. And in a more uncertain global market and with a slow pace of exits, the board is poised to keep growing.