'Full games, not experiments.' https://www.bit-tech.net/news/gaming/2017/02/10/valve-three-vr-titles/1
European trademark application a hoax? http://www.bit-tech.net/news/gaming/2013/10/07/hl3-deregistered/1
Claims of a 2014 launch scuppered. http://www.bit-tech.net/news/gaming/2013/07/29/valve-half-life-3-bogus/1
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