Yahoo has tripled down on what was already the largest data breach in history, saying it affected all three billion of its users, not the one billion it revealed late last year.
The company announced Tuesday it's providing notice to additional user accounts affected by the August 2013 data theft.
The breach was previously disclosed by the company in December.
Following its acquisition by Verizon in June, Yahoo says it obtained new intelligence while investigating the breach with help from outside forensic experts.
It says the stolen customer information did not include passwords in clear text, payment card data or bank account information.
The Associated Press wire services helped contribute to this report.