Halo 4 one of the most anticipated games this year has been leaked onto torrent sites like Piratebay, 1337x, h33t, Bitsnoop. Halo 4 has already been downloaded thousands of times from torrent sites a month before its official release. Getting a game like Halo 4 a month before its official release is much tempting & is proving to be a costly matter to Microsoft.
Pre-Order cost of Halo 4 at Amazon is 60$. If Halo 4 has been downloaded 10,000 times then Microsoft has already lost a million dollars. And at this rate this number seems to be minute as illegal torrent downloads are surging day by day & loss to Microsoft will reach many Millions even before the official release.
TorrentFreak News found atleast 2 active Halo 4 torrents on Piratebay with many peers, one of them is an 8GB version while other is a 16GB version.
Halo 4 will be officially released in November 2012,until then the people who can’t wait for the game are heading on to torrent sites.

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The same thing happened with the Win8. RTM is available on the torrents and thousands of peers got the OS activated through a KMS server. (not working anymore though)