Analyst estimates the breach could shave $100m to $200m off the closing price of the deal
Many of the accounts are old and unused, and login details for sites such as Flickr are thought to be caught up in the attack
Yahoo is already haemorrhaging users, traffic and advertising to rivals Google and Facebook - the leak of half a billion users personal details will magnify its problems.
Yahoo will be informing people if their personal information was disclosed – but it’s worth proceeding if you’ve been caught up in the hack either way
Is it because Britain makes it so easy for foreign firms to buy up its developing stars? Is it cultural? Is it down to a lack of available finance? Britain needs to find answers to these questions if it wants to create more technology stars
She's regularly pulled off all-nighters during her time at Google
Uber admitted in February that it was losing around $1bn per year in the country amid fierce competition
The company is now far more than just a social network and has blown Wall Street away with its latest results. But should we be concerned about its growing power?
The deal marks the end of the six-month sale process and the end of an era for a company that once defined the internet
Yahoo shareholders are fed up with a downturn in the company's revenue
The huge database is one of the biggest ever discovered
Yahoo has been looking for a buyer for its core business since February
Yahoo CEO Marissa Mayer says company is considering selling its Internet business; Microsoft buys UK AI firm SwiftKey
Plans include sacking 15 per cent of the workforce - some 1,600 jobs
Struggling internet giant's chief executive says move is part of 'a strategic plan'
Technology has the potential to change the lives of older people. Grow up, says Kevin Maney