Stock value of companies drop 7.5% after data breaches

Reports reveals a decrease in stock value after companies suffered a data breach.

The report, Kings of the Monster Breaches, conducted by Bitglass, analysed the top breaches from the past three years including the Marriott breach of 2018, Equifax breach of 2017, and Yahoo! breach of 2016.

Altogether the mean number of individuals directly affected by each breach was 275 million. The research revealed that the breaches cost their companies an average $347 million in penalties, legal fees, remediation costs and other expenses. 

Companies that were publicly trading, suffered a drop in stock value by 7.5% after a data breach. However the report revealed that it took 46 days, on average, for the companies’ stock prices to return to their pre-breach levels. Despite these findings, Equifax is still yet to return to its pre-breach levels. The Equifax breach resulted in hackers gaining access to sensitive data including credit card numbers, Social Security numbers, full names, dates of birth and addresses.

Rich Campagna, chief marketing officer of Bitglass said:

“The largest breaches over the past three years have caused massive and irreparable damage to large enterprises and their stakeholders around the globe.

“This should serve as a stark warning to organisations everywhere. If massive companies with seemingly endless resources are falling victim to external attacks, then companies of all sizes must remain vigilant in their cybersecurity efforts.

“It is only by taking a proactive approach to security that breaches can be prevented and data can truly be kept safe.”

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