InsiderFlow › Glossary › What is a dark pool?
Dark pools are private exchanges where large orders trade without being visible before execution: the submerged (and legal) market of institutions.
If a fund must sell 5 million shares, showing them on the public market would crash the price before the sale is done. In dark pools, orders stay hidden until execution, protecting whoever moves big blocks.
An estimated 30–40% of US equity trading happens off public exchanges, between dark pools and market-maker internalization. Trades are still reported after execution: opaque before, transparent after.
On InsiderFlow these concepts come alive on real data: what big funds and insiders are buying, explained every day.
Yes, SEC-regulated: the opacity only concerns the pre-execution phase.
The debate is open: they reduce big orders' market impact but drain liquidity and transparency from the public market.