Exchange Netflow
The value of an asset moving into exchange-labeled wallets minus the value moving out, measured over a period.
The metric is built by tagging exchange deposit and treasury wallets and summing transfers in each direction. It is commonly narrated as assets moving onto exchanges to be sold and off exchanges into longer-term custody, and that inference is much weaker than the narration suggests. Exchanges reorganize their own wallets, migrate custody providers, move collateral for derivatives, and rotate cold storage, all of which appear as flows. The label set is maintained by third parties and rarely confirmed by the exchange, so a mislabeled or newly created wallet can shift the series in either direction. It is best read as a description of labeled balances changing rather than as evidence of anyone's intent.
In practice
A custody migration in which an exchange moves assets to newly created wallets can register as a large outflow until the new addresses are labeled.
The common misunderstanding
Netflow does not observe intent: a deposit is not a sale and a withdrawal is not a commitment to hold, and much of the series can be exchanges moving their own funds.