Unfortunately, I threw away the FutureNet manuals last year (who would
ever need a FutureNet manual again?!), but my recollection is that they
didn't contain the netlist format anyway. I wrote a utility in 1995 to
compare Cadence and FutureNet netlists; I've just had a look at the
code, and it appears that I did it without a spec, although I had all
the manuals. You can have the source if you want, for what it's worth.