Why the exploding secondaries market is hard to pin down

Core Insights - The secondaries market is significantly large and expanding, but its true size remains uncertain due to structural opacity and lack of comprehensive data [1][3][6] Market Size and Estimates - PitchBook estimates that U.S. direct secondaries will trade between $62.5 billion and $120.9 billion in 2025, indicating a substantial margin of error [2] - The midpoint estimate of the secondaries market is $91.7 billion, with an additional $14.6 billion from GP-led venture secondaries, totaling $106.3 billion for U.S. venture secondaries in 2025 [6] Market Dynamics - The secondaries market is characterized by a lack of transparency, with many investors operating with incomplete information, similar to public market behaviors [3][4] - A significant concentration exists within the market, where the top 20 startups on the private stock marketplace Hiive accounted for 86.4% of secondary trading value in Q4 2025, with the top five companies alone making up 55.6% of that volume [5]