[baronspam]

So, questions on Nuyen.  What country actually issues nuyen and controls the money supply for it?  Is it perhaps the corporate court?  If it is an "international" currency it would either need to be an international organization, or it would need to be the largest/strongest economy in the world, basically the currency so good everyone wants it. 

Is there any formal explanation of this anywhere?

[Crimsondude]

It was originally Japan, but then the Z-OG Bank took over as the central bank for the nuyen. It's been discussed in all of the corporation books.

[baronspam]

Ah, found this article.  Looks like it is basically the corporate court.

http://shadowrun.wikia.com/wiki/Zurich-Orbital_Gemeinschaft_Bank

[Nath]

It was originally Japan, but then the Z-OG Bank took over as the central bank for the nuyen. It's been discussed in all of the corporation books.

As far as I remember, the fact that the nuyen is the Japanese currency wasn't specified until Shadows of Asia (which also happen to be only the second book, after Year of the Comet, to cover Japan at all). It does state "The Yamato Act also officially changed our national currency to the nuyen, deepening the country’s economic dependence on its largest corporations." The latter part suggests the nuyen was, from the start, and possibly before its adoption by the Japanese government through the Yamato Act of 2012, a corporate currency (albeit obviously not issued by the Corporate Court or the Zurich-Orbital Gemeinshaft Bank, as none of them existed at that point).