The Impact of Data Breaches on Public Companies Stock
See charts for AET, CUS, EK, GPS, HUM, MHS, RL, SBUX, TJX
This post is not meant to come to any conclusions or be the result of a comprehensive study. Simply some raw data to be used in conjunction with other research in the hopes others will start looking at this aspect of the problem.
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Andy Peet | Feb 11, 2009 | Reply
Is there another article discussing these breaches?
The impact of the breaches on stock price does not appear conclusive from these tickers. There appears to be some evidence for MHS, CVS, AET and TJX; but the others are far less conclusive.
I think this is a great idea for analysis, but do you have some other comments as to why some breaches appear to affect stock price whilst others do not?
Editor | Feb 11, 2009 | Reply
There are several data breach studies that include this information. One of them is at http://www.perimeterusa.com/reports/Healthcare_Data_Breach_Study_charts-SCM.pdf. It begins discussing this information on about page 16. You are correct. The impact is sporadic at best. There are several factors that seem to weigh in on the impact to stock. The size of the breach, how publicized it is, the type of data exposed, etc. But even with all that taken into account, it seems that although you can build a story around the impact to stock, it is short term. People seem to have short memories for such things.
Allan Friedman | Feb 11, 2009 | Reply
I have a paper with Alessandro Acqisti evaluating the impact on share price a little more systematically: “Is There a Cost to Privacy Breaches? An Event Study,” Alessandro Acquisti, Allan Friedman, and Rahul Telang. Proceedings of the International Conference of Information Systems (ICIS), 2006. http://www.heinz.cmu.edu/~acquisti/papers/acquisti-friedman-telang-privacy-breaches.pdf
We’re working on an updated version of the paper incorporating more recent data and hope to have a working paper by the end of the spring.