Directors' purchases "talk" and buybacks "whisper"?

With a unique daily data set from the London Stock Exchange we find that directors’ purchases trigger a higher market reaction compared to share buybacks. Moreover, we find evidence of market timing for both directors’ purchases and actual share buyback transactions, but the former display better short-term timing ability and the latter better medium-term timing ability. We also find a number of concurrent trades for which the share performance is mostly driven by directors’ purchases. However, the non-concurrent trades show that directors’ purchases are not informative, contrary to share buybacks which display a better post-event performance.