On the Reliability of I/B/E/S Earnings Announcement Dates and Forecasts

We add to the concerns raised in Ljungqvist, Malloy and Marston, 2009, Rewriting History, Journal of Finance, 64, 1935-1960, about the reliability of the I/B/E/S data provided by Thomson Reuters (TR). Many of the dates reported as earnings announcement dates are not earnings announcement dates; there are inconsistencies between these dates and those reported in Worldscope, another TR database; and summaries of financial analysts' forecasts can be misleading. Following discussions with the authors, TR has reviewed approximately 2 million records and is in the process of correcting some 50,000 of them. Further reviews are under way