It’s all up to Valve
The possibility of “Left 4 Dead 3” heightened all the more in December last year when a game developer at Turtle Rock revealed that he is not ruling out the possibility of himself working on the video game if Valve wants it that way. Valve holds the IP to the game so they’re pretty much in charge for its direction.
It was actually Turtle Rock Studios co-founder Chris Ashton who made the remark during an interview where he was asked about the status of the game.
As early as 2013, a visitor to Valve’s headquarters in Washington has seen a “Left 4 Dead 3” reference in an internal company changelog.
Valve did not make any statement when it came out of the media and the internet then. Ashton said that a lot of people in his team at Turtle Rock Studios, including himself, would jump at the opportunity to work on “Left 4 Dead” again because it was a game that they sort of invented in the first place.
He also shared that “Left 4 Dead 3” will be pretty much like “Evolve” when it comes out on the next gen gaming consoles since that has been their signature gaming style.