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He said there are a lot of issues restricting the release of Shenmue.
http://www.neogaf.com/forum/showpost.php?p=142176208&postcount=502
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About this bit of information; there was another Gaffer/insider who (in question about " Why SEGA didn't make a Shenmue HD Collection for PS360 again? ") said:
Afaik, it's mostly due to legal/copyright reasons.
back in '12 you may remember that Sega went into a port spree. JSR, Nights...they thought it was a great idea, with very low risk and nice proft potential since, well, they don't want to fund traditional AAA anymore. Multiple ports were in development, among them was the canceled Skies of Arcadia port.
Shenmue case was special since not many people know this, but apparently the engine for both games uses licensed technology. It's not Bink Video or Sofdec codecs, apparently it's related to the very own engine.
Well, the thing is, according to what I've been told, the owner of those technologies folded years ago, and it's not clear who owns the copyright now.
Someone shown Sega a working Shenmue prototype for Xbox 360...but after disappointing sales by JSR and Nights, they didn't care enough to bother with the legal hassle. So it never went through the prototype stage, and the Skies of Arcadia port was canceled.
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[Source: http://shenmuedojo.net/forum/viewtopic.php?f=5&t=46868&p=1068524#p1068524]