A US court has ordered Facebook and other defendants to pay $500m (£395m) after finding they unlawfully used a firm's virtual reality technology.

The jury found Oculus, which Facebook bought in 2014, used computer code belonging to video game developer Zenimax to launch its own VR headset.

Oculus said it was "disappointed" and would appeal against the ruling.

The case threatened to overshadow Facebook's latest results, which showed it enjoyed a strong end to the year.

Facebook's net profit more than doubled to $3.6bn in the fourth quarter.

The social network was helped by 53% growth in advertising revenues, and said it was on course to hit two billion users in the first half of 2017.

'Trade secrets'

Shortly before the results came out, the court awarded Zenimax damages from Facebook, Oculus and Oculus executives following a three-week trial.

Zenimax argued that its early innovations in virtual reality were unlawfully copied when Oculus built its own headset, the Rift.

"We are pleased that the jury in our case in the US District Court in Dallas has awarded Zenimax $500m for defendants' unlawful infringement of our copyrights and trademarks," said Zenimax chief executive Robert Altman.

The co-founder of Oculus, Palmer Luckey, was also found to have broken a non-disclosure agreement with the firm.

However, the jury ruled that none of the defendants misappropriated Zenimax's trade secrets.

Few people will have given Mark Zuckerberg as many headaches as Palmer Luckey.

The 24-year-old founded Oculus VR, and when Facebook stepped in to buy the firm for $2bn, he was rewarded very handsomely indeed. Then it went a bit downhill.

First, it was revealed he was using some of that money to fund a pro-Donald Trump trolling campaign, which led to Facebook removing him from public view. He didn't even turn up to his own company's developer's conference last year.

And now, a jury has ruled that he broke a non-disclosure agreement that'll mean $500m in damages (unless Facebook wins on appeal).
Mark Zuckerberg doesn't display many emotions - but you wonder what he'll be like behind closed doors on this one.

As it stands, Palmer Luckey is still a Facebook employee, but what he's doing there is anyone's guess - the company won't even tell me his job title.

Source: BBC