possibility of massive lawsuit vs yahoo?

Can it be done?

Yahoo blamed a “state-sponsored actor” for the huge theft, which it said occurred in 2014 when thieves hacked into the Sunnyvale tech firm’s data centers. Neither Yahoo nor federal investigators indicated what nation was believed to be behind the attack.

Yahoo said it had no evidence the hacking entity was still in its system, and that the company was working closely with law enforcement on the matter.

“We take these types of breaches very seriously and will determine how this occurred and who is responsible,” the FBI said, confirming its role in the investigation.

I don't have interest for this matter.

It can certainly be done, but whether or not it'll succeed is doubtful. It certainly wouldn't win on the grounds of claiming Yahoo was negligent in being hacked--since ultimately, perfect security is impossible--but on the grounds of having waited two years to reveal it.

I think the bigger opportunity for a class action lawsuit against Yahoo is in their complicity with NSA requests. Even if they shield themselves in the United States, there's also the European courts, among others, to contend with.

Why not sue the Chinese government instead ?

In Chinese courts or American ones? It would never happen in China. With the law in the United States looking to do away with sovereign immunity, it's certainly doable here. They'll retaliate, of course, loosing their legal system on American assets while pulling their own out of the United States to hedge against future lawsuits--starting a tit-for-tat economic war for very little reward.

If you can't show that you have suffered a loss, you have no case.

If you have suffered some loss due to personal data theft, you'll have to show that this information was extracted from Yahoo.

If you show that you suffered a personal loss and Yahoo was the source of this, you still need to show that they were negligent in losing your data.

You may want to sign up to a future class action suit, if one arises. Otherwise you don't really stand a chance taking on such a huge company.

I think I just saved you about $300 in a legal consultation fee.

Well, of course I didn't mean individual action, but 500.000.000 people...

I used to have a credit card ages ago that was part of a class action suit that I had no idea was going on. One day I got a credit for $5.25 on a bill. The lawyers who ran the suit pocketed millions.