This seems odd for a private company that has been believed to be doing well, given the huge success of its Steam software delivery and management platform. Even though management aren't saying much (see Gabe Newell's response below) it's not a good sign from a company which hasn't finished any projects recently. Ultimately, though the reasons for the firings isn't known at this point.
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This all started when Jeri Ellsworth, hardware designer, tweeted three days ago that she had left the company, "Yup. Got fired today. Time for new exciting projects". Doesn't enlighten us much really, but this appears more to do with Valve asking its sacked staff not to say anything, rather than Ellsworth not wanting to tell. Forbes describes Ellsworth thus:
So it looks like her departure may mean that the upcoming Steam Box will end up being designed and built by a third party rather than in-house, which seems a shame to me. It would have been interesting to see what unusual hardware Valve came up with.Ellsworth had been involved in the prototyping and design of controllers for Steam’s Big Picture Mode, with an eye towards the long-rumored Steam Box. Ellsworth, who joined Valve in 2011 and moved to Bellevue’s campus last August, is a self-taught hardware hacker and pinball machine enthusiast.
Another notable departure, reportedly, is Valve's Director of Business Development, Jason Holtman. Why? Because he has been involved in making the company what it is today, especially the Steam online store, Steamworks and the licensing of the Source engine. All of these are significant assets for the company. Holtman had been with the company since 2005, just two years after the Steam platform was launched.
Forbes contacted Valve for a statement about these departures and surprisingiy got one from CEO Gabe Newell, although, unsurprisingly it didn't say all that much:
That Newell is staying tight lipped isn't surprising, since a private company isn't obliged to reveal details of internal staffing decisions and movements, but more importantly, has good reason not to.We don’t usually talk about personnel matters for a number of reasons. There seems to be an unusual amount of speculation about some recent changes here, so I thought I’d take the unusual step of addressing them.
No, we aren’t cancelling any projects. No, we aren’t changing any priorities or projects we’ve been discussing. No, this isn’t about Steam or Linux or hardware or [insert game name here]. We’re not going to discuss why anyone in particular is or isn’t working here.
Source [sic]: Forbes