Working-capital changes in the cash flow statement — sign logic down to modeling depth?

Δ in an asset item (other than cash) hits OCF with the opposite sign. Δ in a liability item (current liabilities) hits it with the same sign. Concretely: AR ↑ by X → −X in OCF (you booked revenue but collected no cash). Inventory ↑ by X → −X (cash tied up in stock). Prepaid expenses ↑ by X → −X (cash already out, expense not yet in the income statement).

AP ↑ by X → +X (you owe more, conserving cash). Accrued expenses ↑ by X → +X (expense booked, not yet paid). Deferred revenue ↑ by X → +X (cash received, revenue not yet booked). Modeling trap: the NWC definition varies — some models include tax payables or dividend payables, some don't. IB standard: model only 'operating working capital' — i.e. AR, inventory, AP, other operating receivables/payables. Cash, debt, and dividends out.