Every position above a reportable level is captured by large-trader-reporting and aggregated into categories. The report shows long, short and spread positions for each group in each market, plus the residual non-reportable bucket. It is the closest thing futures markets have to a public positioning map.
The three-day lag is the main limitation. In a fast week the Tuesday snapshot published on Friday can be badly stale, and the data says nothing about the prices at which positions were built.
Analysts use it mainly for extremes rather than levels. When managed-money holds a record net long and commercial-trader positioning is a record net short, the market is crowded and vulnerable to a reversal — though "crowded" can persist for months.
Example: crude COT shows managed money net long 300,000 contracts against a five-year average of 180,000 and a record of 340,000. That is a positioning warning, not a sell signal, and it has been at similar levels for six weeks.
Related: disaggregated-cot, managed-money, commercial-trader, large-trader-reporting, non-reportable-positions