IbizaPocholo
NeoGAFs Kent Brockman

Valve Elaborates On Early Left 4 Dead 3 Rumors, Portal VR Ideas – IGN Unfiltered - IGN
Valve's Robin Walker elaborates on the rumored Left 4 Dead 3, Portal VR, and a whole lot more in this month's IGN Unfiltered.
The official Valve statement on the Left 4 Dead 3 rumors said, "We did briefly explore some Left 4 Dead next-gen opportunities a few years ago, but we are absolutely not working on anything Left 4 Dead-related now, and haven't for years."
What the team at Valve was experimenting with was Source 2, and Valve's Robin Walker explained how it happened. "We used parts of a Left 4 Dead level as the first bit of level geometry to start building in Source 2, so a bit of that got out. It was essentially a rendering test, and people thought that meant we were working on Left 4 Dead."
Unfortunately for Left 4 Dead fans, that wasn't the case. Walker continued, "We built lots of different things as part of building technology in Source 2... There were groups here who would generate a product in mind that would attempt to be a target for Source 2, and so a couple of those were Left 4 Dead-related things, but none of them reached the point where we were like, 'now this is a product team that we're going to build a big product around.' They were more tools for moving Source 2 forward."