This is the cleanest available proxy for professional speculative positioning. Managed money is dominated by trend-following systems, so its net position is highly correlated with recent price direction, and its extremes mark crowded trades.
Because these funds trade on rules, their behaviour is partly predictable: they add on breakouts and cut on reversals. That predictability is itself traded — sharp counter-trend moves often accelerate as managed money is forced out.
Example: managed money flips from net long 180,000 copper contracts to net short 40,000 over three weeks. That 220,000-contract swing, at 25,000 lb per contract, is 5.5 billion pounds of notional turnover driven by systems, not by any change in mine supply.
Related: disaggregated-cot, non-commercial-trader, commitments-of-traders, speculator, copper-futures