Mr Tact has it right. The top execs at Valve are scoping the most obvious way to score a huge pile of $$ now that they are in the 40-50's age bracket. Then they'll happily leave Valve within 6 months after the buyout.
I can't say that this isn't the case, but it bears pointing out that Valve co-founders Gabe and Mike Harrington had boatloads of money before forming Valve as before that they were both low-numbered employees at Microsoft.
Stephen "Blue" Heaslip
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