Many transactions are priced on a cash-free, debt-free basis with an agreed level of normalized working capital delivered at closing. If measured working capital is below the target, the purchase price may be reduced; if it is above the target, the price may increase—subject to the agreement.
There is no universal formula. The definition of included current assets and liabilities, accounting policies, seasonality, unusual balances, and post-close true-up mechanics are negotiated transaction terms. A working-capital peg is the agreed target, not an extra amount the seller automatically receives.