the market value impact of operational risk events for us banks and insurers j david cummins wharton school christopher m lewis hartford insurance group ran wei december 23 2004 keywords banking event study jel codes g21 g22 g14 g28 opinions expressed in this paper are those authors do not necessarily reflect views or corresponding author 3303 steinberg hall dietrich 3620 locust walk philadelphia pa 19104 6302 phone 215 898 5644 fax 0310 email upenn edu abstract conducts an analysis on values companies using opvar database we focus financial institutions because increased regulatory scrutiny losses these industries covers all publicly reported affecting traded from 1978 2003 that caused at least 10 million a total 403 bank 89
