Non-commercials are hedge funds, CTAs and other large financial players. Their net position is the number quoted in press coverage as "speculative positioning", and it tends to be trend-following: long in uptrends, short in downtrends, with extremes clustering near turning points.
The category also reports spread positions separately, which matters because a fund holding 50,000 long and 45,000 short across months is not directionally exposed at all even though it holds 95,000 contracts.
Example: a report showing non-commercials long 210,000, short 60,000 and spreading 40,000 gives a net long of 150,000, while total non-commercial open interest is 310,000 — half of it market-neutral.
Related: commercial-trader, managed-money, commitments-of-traders, speculator, disaggregated-cot