Diversification, Size and Risk: the Case of Bank Acquisitions of Nonbank Financial Firms
研究了1991至2012年间银行收购保险公司和证券公司的风险效应，发现银行与证券公司合并风险更高，银行规模是风险的重要决定因素，而多元化则不是。
Abstract We investigate the risk effects of bank acquisitions of insurance companies and securities firms between 1991 and 2012 using a newly constructed dataset of M&A deals. We examine risk changes before and after deal announcements by decomposing risk into systematic and idiosyncratic components. Subsequently, we investigate the relationship between risk and diversification by modelling the determinants of risks. We find that bank combinations with securities firms yield higher risks than combinations with insurance companies. Bank size is an important and consistent determinant of risk whereas diversification is not. Our results inform the continuing debate on diversification versus functional separation of bank activities.