Abstract ：
This article analyzes the leading mergers that give insiders the strategic advantage of becoming a Stackelberg leader in free-entry markets. It is shown that mergers enhance welfare if and only if they are profitable. It is also shown that the welfare-deteriorating leading mergers do not appear in equilibrium if the entry costs are sufficiently large.

Keywords : Horizontal mergers; Stackelberg competition; Free entry
JEL Classification : L13; L22