Changes in Working Captial (FCF, WCInv) change, always, current, capital, like

chunty

When I think about working capital, and in turn WCInv, the term used in the FCFF & FCFE formulas, I always think about the change in current assets and current liabilities. But it seems like the calculation of WCInv excludes changes in cash, and ST debt. Any other current assets/liabilities excluded from the WCInv calculation?