If you believed that Valve is working on Left 4 Dead 3, then you might be mistaken. IGN has recently announced that Valve has shut down any possibilities of Left 4 Dead 3, as the company is moving away from that project, at least for now.
IGN has discovered the neglects by Valve on a new Left 4 Dead title, as the development team of Valve has called upon misinformation once it is seen gaming media raising voice about the third installment of Left 4 Dead.
As Valve stated:
We’ve seen rumors to this effect for the last couple of months. We did brieflt explore some Left 4 Dead next gen opportunities a few years ago. But we’re absolutely not working on anything L4D related now, and haven’t for years.
Therefore, the stories found about Left 4 Dead 3 or leaks that are destined to expose the development of the next series of the title are most likely fake. A next-gen Left 4 Dead title is probably not intended to release anywhere in the near future.