[UPDATE: Confirmed]
Sean Murray himself has confirmed the August 12th release date for No Man's Sky's PC version in an effort to make it global. Here is the tweet:
PC NMS release will now be global and will be August 12th worldwide. It's so important we get it right and make the best version we can
— Sean Murray (@NoMansSky) August 5, 2016
Original Story: Ever since No Man's Sky was delayed and got a new release date, the universale belief was that the PS4 version and the PC version would be releasing at the same time: August 9th in North America, August 10th in Europe and across the world on August 12th.
An update to the official No Man's Sky website (via NeoGaf) is suggesting that this is not the case. Instead, the PC version of the game will release on August 12th, making the game a PS4 exclusive for at most three days (depending on where you live).
Steam, GOG and Humble have yet to update their listing for the game, still claiming that it will release on August 9th. So there's hope that this is some kind of typo on the site, otherwise, this means that the release date was changed roughly three weeks before the game was set to launch.