The Yahoo data breach has given prospective buyers Verizon cause for concern, potentially putting the $4.8bn acquisition at risk.
At a roundtable, Verizon’s general counsel Craig Silliman said that it was “reasonable” for Verizon to believe that the impact of the breach was “material”.
This references specific legal language in the deal that says Verizon can withdraw if an event occurs which “reasonably can be expected to have a material adverse effect on the business, assets, properties, results of operation or financial condition of the business.”
Silliman said that the results of Yahoo’s investigation would determine how big the impact was, with the onus on Yahoo to demonstrate that it was not “material”.

The massive data breach targeting Yahoo reportedly affected 500 million accounts.
According to Reuters, Yahoo said: “We are confident in Yahoo’s value and we continue to work towards integration with Verizon.”
Yahoo has already been criticised by a prominent group of US senators for its failure to promptly disclose the breach, taking over two years to do so. The revelation of what actually caused the attack could be just as damaging if the internet giant had somehow failed to take basic steps to defend the data.
Earlier in October it was suggested that Yahoo might see $1 billion slashed off its price tag in its acquisition by Verizon as controversies mount around the cyber attack.
The New York Post reported that Verizon was pushing for the price to be cut with fierce resistance by Yahoo, according to the New York Post.
Yahoo recently discovered a colossal cyber attack in 2014, which led to over 500 million email account details being stolen from within Yahoo’s network.
The situation worsened when Reuters revealed in a report that Yahoo had secretly built a software programme that would search customer emails for specific information requested by US intelligence officials at the National Security Agency or FBI.