"Firefly came from (the aquisition of the Spain based) Reyes Infografica..."

My impression was that FireFly came from Pixels3D - e.g.

"Tempest is the rendering engine of PiXELS 3D. As stated in the Poser 5 manual and on the Poser 5 box, Curious Labs has licenced the Tempest rendering engine and its material system. The FireFly renderer can be considered a sibling of Tempest, and the Material Room would be a sibling of ShaderMaker Pro. " - http://www.keindesign.de/stefan/poser/firefaq.html#13

Whether Pixels3D got anything from RI, I don't know. I remember their plugins from years ago. It was cool that the gave the Max3 versions away free :-) 

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