from a discussion regarding insurance:

there is no distinction or seperate classification for
framebuilders. we are all "bicycle manufacturers" and,
as such, lumped in with the odds facing the risks assumed
when writing policies for all makers of all sizes, and it
also considers the middlemen along the way that assemble
these bicycles in the stores as well as service them routinely.
no matter how limited your output, how fine your product,
how few - if any -times one of yours has fallen apart, in
the eyes of the underwriters, you're manufacturing a bicycle.
this stymied me from day one, and for a brief period in the
80s i switched to classification as a welder - but ultimately
lost that due to the fact that if the "welded object" were to
ever see life as a bicycle it would violate the terms of the
agreement. the reality is that frames built by independent
builders 1) are not made in high enough numbers to constitute
a classification and 2) there aren't enough records kept
because these builders don't have consistant long-term business
histories to examine and 3) no matter; their frames are used
in bicycles carrying a host of parts from 20 other suppliers.