Is it possible that, out there somewhere, someone has produced a book
which gives details of all the piano roll manufacturers, their output
and eventual demise?  Something which tells me which company took over
which and where rolls were continued under a different label?

As a new player piano owner (just over 14 months) and an enthusiastic
collector of rolls, I can see that some performers worked for several
companies, or maybe the company was taken over.

I would love some sort of guide which can lead the way.  I realise
there were many millions of rolls made by hundreds of companies,
but perhaps the major players in the field (no pun intended) have
been catalogued and defined.

Best wishes
Stephen Simpson
http://www.happycowmusic.co.uk/