This paper adds to recent evidence on market inefficiency in processing information in earnings reports. It documents that short positions taken in sample stocks which did not report earnings by the date expected during the sample period, 1971–1976, would have been abnormally profitable, before transaction costs. This is because late reports, on average, revealed bad news which was not anticipated in market prices prior to the report date. The magnitude of the average abnormal returns is in the order of 1.0% over 20 days but is larger for smaller firms in the sample and positively related to the length of the reporting delay. The paper also documents that long positions taken in stocks reporting early with good news would have generated abnormal returns of approximately 1.0% on average over a 20-day holding period.