Yahoo recently discovered a huge cyber attack that took place in 2014.
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.