http://metro.co.uk/2015/03/03/htc-co-operating-with-valve-on-half-life-vr-5086443/
Then valve denies.
HTC
Half-life Three Confirmed.
Quote
At the recent Mobile World Congress trade fair in Barcelona the BBC asked HTC chairwoman Cher Wang whether Valve were making a new Half-Life for the VR headset.
After commenting that she preferred Dota 2 and Portal, Wang answered: 'We are co-operating with Half-life, and I think… I hope, you know, it will be on it.'
That's all she said though, and it could easily be that she's just talking about adding VR support to the existing Half-Life games - which has already happened with rival VR headset Oculus Rift.
You'll certainly note that at no point does she use the word 'new' or mention the number three.
All Valve has said on the matter is that they're not planning to make an announcement, with employees reportedly 'surprised' by Wang's comment.
Then valve denies.
HTC
Half-life Three Confirmed.