Prior research demonstrates that manufacturing firms increase production (relative to sales) to transfer fixed costs from cost of goods sold (COGS) to inventory accounts, thereby increasing income to reach or surpass earnings thresholds. We examine how the market reacts to this earnings management strategy. We find that investors respond positively to inventory growth based on an expectation of increased future sales; however, this signal is weaker for inventory manipulators. Further, the market premium from meeting or beating analyst earnings forecasts by manipulating inventory is smaller than the premium for achieving this threshold absent inventory manipulation or through accrual manipulation. Finally, we examine firms considered to be “serial” inventory manipulators, finding that the market consistently discounts earnings beats for these firms, suggesting that inventory manipulation erodes investor confidence in firms' earnings. Collectively, our results provide new insights into a challenge facing operations managers and finance managers in manufacturing firms.