A current developer at Valve says that the team is working on Half Life Episode 3 and plans to launch the game in late 2014 on the PC, the PlayStation 4, the Xbox One and current-generation consoles.
A little-known site called NSS says that it spoke to a designer named John Guthrie via e-mail and that he said, "We hope to have the first trailer ready for E3 2014, which we (after several times not attending) will finally come back to."
The developer also says that the game will be strictly single player and will use many of the characters that players are familiar with.
The comments section of the article already has comments from someone claiming to be the real Guthrie who says that he never gave such a statement.
A new Half Life is one of the most expected video games, but Valve has not offered any sign that it is actively working on a new installment in the series.