PE's Middle-Market Deal Boom Is Moving Downmarket as $860 Billion 'Zombie' Problem Grows

Private equity investors are increasingly turning to smaller deals as uncertainty weighs on larger transactions, while a growing backlog of aging portfolio companies leaves billions of dollars of capital tied up in investments that have yet to find an exit.

U.S. middle-market private equity deal value fell 8.7% sequentially to $92.4 billion in the second quarter, according to a new PitchBook report. Deal count, however, jumped 25.7% to 1,090, pointing to a market where sponsors are still deploying capital but favoring smaller transactions.

The median middle-market deal size fell to $151.9 million in the first half of 2026, down from $179 million in 2025.

Deals between $25 million and $100 million were the strongest segment in the second quarter, generating $16 billion in value, up 70.6% from the prior quarter. It was the only middle-market size category to post sequential growth in both deal value and deal count.

The shift comes as sponsors contend with tariff uncertainty, higher-for-longer interest rates and the potential for artificial intelligence to disrupt some industries and business models.

Middle-market transactions accounted for 61.9% of total U.S. buyout value in the second quarter, up from 54.8% a year earlier. At the same time, megadeal value plunged 43.5% year over year.

The $860 Billion Problem

The bigger challenge for private equity may be what happens to the companies already sitting in portfolios. U.S. buyout funds that were more than seven years old held more than $860 billion in net asset value as of the end of 2025, according to PitchBook. The research firm also identified 2,536 U.S. portfolio companies that had reached or passed the traditional five-to-seven-year exit window as of June 30.

Not all of these companies are distressed or stuck. Some sponsors are deliberately holding strong businesses longer to capture additional growth. But PitchBook said the growing population of older investments includes companies facing stalled earnings, elevated leverage or limited buyer interest — making attractive exits increasingly difficult.

The weak exit market is adding to the pressure. Middle-market exit value dropped 19.5% sequentially to $24.7 billion in the second quarter, the lowest quarterly level since the second quarter of 2020. Exit value was also down 14.2% from a year earlier, despite the number of exits increasing 2% to 239.

That creates a difficult equation for sponsors: new investments are getting done, but older investments are taking longer to sell.

Longer holding periods can delay distributions to limited partners and slow the recycling of capital into new funds. That could become increasingly important as fundraising itself becomes concentrated among fewer managers.

Middle-market fundraising totaled $69.1 billion across 71 funds in the first half of 2026. PitchBook estimates the full-year pace at roughly $140 billion, slightly above the $124.7 billion raised in 2025.

But the number of funds raised is on track to decline for a third consecutive year, signaling that LP capital is increasingly flowing toward a smaller group of established managers.

For now, sponsors continue to find opportunities in smaller, more manageable transactions.

The bigger test for the industry, however, may be whether it can turn its aging portfolio of investments back into cash — before today’s smaller deal boom creates an even larger exit backlog tomorrow.

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