Mergers and Acquisitions
: implications for acquirers' shareholder wealth and risk

  • Ibrahim Yousef

Student thesis: Doctoral ThesisDoctor of Philosophy


This study analyses the impact of M&As on acquiring company shareholder wealth and market risk through empirical evidence based on event study methods and cross-sectional regressions. The hypotheses investigated relate to the relevance of target status, method of payment, acquirers‘ bidding experience, and diversification motives. The evidence is based on a comprehensive sample of M&A transactions comprising 46,758 initial bids announced in 180 countries over the period 1977-2012, covering 88 industries. The study also investigates the relevance of deal and firm-specific factors affecting the likelihood of the success or failure of a deal once announced. The results of the event study indicate that acquirers‘ abnormal returns are not influenced by uncertainty about whether the announced deals will succeed or fail, which is consistent with the efficient market hypothesis. The event study evidence also confirms that acquirers‘ gains are most significant in cross-border M&As with acquirers located in developed countries and targets in developing countries. Further evidence from cross-sectional regressions confirms that cross-border and cross-industry diversification yields significant announcement gains for acquirers, although in comparison with domestic and focussed deals, such deals carry a greater risk of failure. Diversification has no significant impact on acquirers‘ market or systematic risk. In addition, the evidence with regard to the impact of target status and method of payment suggests that acquirers‘ gains are most significant in stock payment deals involving private or subsidiary targets, while stock payment deals involving publicly-listed targets yield lower returns. In general, cash payment for acquisitions serves to reduce the negative impact of acquiring public targets, while stock payment enhances the positive impact of acquiring private or subsidiary targets. Correspondingly, acquirers‘ market increases with the acquisition of non-public targets, while using cash payment reduces this risk. The overall findings in this regard are robust across various samples and are generally associated with the existence of information asymmetry between acquirers and targets. Finally, the findings reveal that acquirers‘ prior experience of bidding in M&A deals is associated with significantly lower shareholder returns for acquirers, and this also increases their risk. This finding, however, is specific to serial acquirers and generally supports the hubris motive.
Date of Award2016
Original languageEnglish
Awarding Institution
  • Coventry University
SupervisorSailesh Tanna (Supervisor), Hui Pan (Supervisor) & Paul Gower (Supervisor)


  • Consolidation and merger of corporations
  • Stockholder wealth

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