Most of them aren't hedge funds, they're private (HFT, Electronic Trading, Botique Firms, Proprietary Trading are all terms you'll hear) so they don't have public data. It is literally impossible to prove without insider information.
However the Virtu Financials, the Citadels, etc, will always exist, and will be doing exceptionally well whether people realize it or not.
However the Virtu Financials, the Citadels, etc, will always exist, and will be doing exceptionally well whether people realize it or not.