The number of short campaigns by hedge funds has dramatically increased over the last two decades. Nearly 80% of campaigns are undertaken by activist hedge funds, particularly those that employ hostile tactics in their long campaigns. Short campaigns are associated with negative abnormal returns of -7%, with aggregate valuation effects similar in magnitude to the gains from long activism campaigns. In contrast to long campaigns, public communication is a critical component of short campaigns. We do not find evidence that such communication is manipulative. Overall, our analysis highlights the importance of short campaigns for understanding the economic impact of activist hedge funds.

中文翻译：

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对冲基金的空头活动

过去二十年来，对冲基金的空头活动数量急剧增加。近 80% 的活动是由激进对冲基金发起的，尤其是那些在长期活动中采用敌对策略的对冲基金。短期活动与-7% 的负异常回报相关，总估值效应与长期激进活动的收益程度相似。与长期活动相比，公共传播是短期活动的重要组成部分。我们没有发现任何证据表明这种沟通具有操纵性。总体而言，我们的分析强调了短期活动对于了解激进对冲基金的经济影响的重要性。