Update:
We have recently been sent a copy of the original Jira archive data, which has provided unprecedented access to the entire project tracker. Other listings in the data files for known and unknown projects include "Stars of Blood", "Return to Ravenholm", "Episode 3"/"Episode 3 Movie", "Hardware" / "Hardware Core", "SteamMMO" / "SteamMMO Core" and "F-Stop". A series of joke groups can also be found in the list, including "WUBWUBWUB...", "yo dawg", "gayben" and many more. "Steam Box" is also listed as an official group, showing that Valve's upcoming pre-build PC is still in development, which actually retains the fan created name internally, but whether or not this will feature as the product's final name remains to be seen. On a related note, Xi3's "Piston" is also referenced as "Piston Test" in the files, which most likely relates to some kind of Source Box related development back when Xi3 and Valve were briefly partnered. Unfortunately, the saved HTML file we have been provided is only a local file, and only gives access to a partially complete list of Half-Life 3 developers as previously shown in our original post.

However, we now have access to the entire list of project groups from within Valve, giving us a clear insight of what exactly is and isn't being worked on within the company's walls. Just remember a lot of the projects we've posted here have already been cancelled years ago. Click any of the links provided in the previous paragraph for a screenshot of the group as listed in the Jira archive.

We have also recently received some more information about the contents of several of the project groups and, while we cannot check the Jira archive to verify the contents, we have no reason to doubt our source. According to our anonymous source, the main Left 4 Dead 3 group contains around 68 people, while one of the subgroup contains "about 40". The total number of employees contributing to the Left 4 Dead 3 project groups combines to make it Valve's third largest project, showing that the game is or was in full development. A set of never-before-seen projects, titled "Cries Unheard" and "Microbe Wars" have also been uncovered, which both only consist of a few select designers. Our source also informs us that the previously unearthed "The Grange" project is most likely nothing at all, as the project group only consisted of a single person.

A series of non-Valve titles also appear in the list including Skyrim, Battlefield 3, Company of Heroes and more, all of which are most likely used for recreational time to organise game play sessions between members of the company. We'll be sure to keep you up to date with more information as we learn more.

Original Post:
Evidence of several internal projects at Valve including Half-life 3, Left 4 Dead 3, Source 2 and many others have been discovered from a mailing list found within project management and bug tracking software, Jira.

Valve were recently forced to react to an issue with Jira. A metaphorical window was left open which allowed people to publicly access Valve's internal tickets. Valve were quick to shut down public access to their Jira database, so we recommend you don't attempt to access it.

The images submitted to us from an anonymous source show several mailing list groups of interest, although we do not have the full list at this stage. The first image shows the mailing group for "Half-life 3" including 42 employees in this cabal, which we believe to be quite a significant number, given Valve employ approximately 300~ individuals. The names of individuals in this cabal are from various development disciplines, many of which you're likely to recognise.

The second image includes the part of the second page for the Half-life 3 group, including ex-valve composer, Kelly Bailey. We hypothesise these mailing lists aren't updated when employees leave, only their mailboxes are suspended. We do however know this list is current, as Paul Pepera, who also appears on the list, only joined Valve in March 2013 after leaving Halo and Destiny game creators Bungie.

The image also shows several "Left 4 Dead 3" mailing lists. We don't know who are in these cabals but, based on these images, we can estimate games further in the development pipeline have multiple mailing lists, suggesting Left 4 Dead 3 is potentially in active development. Unfortunately, Half-life 3 only had one group suggesting it's either inactive or in developmental infancy.

The third image shows several Source 2 groups. Source 2's development is no secret, however the number of groups suggest the engine is very deep into development, which comes as no surprise. The fourth and final image, shown below, highlights several other groups including the curiously named "The Grange". Unfortunately we have no other information regarding this mystery group/project, and whether or not it is still active remains to be seen.

Throughout the images you will notice some groups for extra-curricular activities or clubs / societies which are used by Valve employees. Some of these are very obscure, but known by our researchers (part of the job description here at ValveTime!) which has allowed us to verify these images are legitimate and are most definitely taken from the Valve Jira database.

We'd be interested in hearing from you if you have any further details. Please also note, access to Valve's Jira no longer exists, so again, please do not attempt to gain access.