In 2005, the Senior Director at Viacom Interactive (part of the company that took over Paramount) took part in a thread here discussing canon policy. His quotes:
Jan 21, 2005 wrote:Right. Only the reference books (tech manual, encyclopedia, etc...) and two books by Jeri Taylor are considered canon outside the tv show and movies.
Jan 21, 2005 wrote:The tech manuals are written by ST production staff, same as the Encyclopedia (Mike Okuda). Since their contents report on what is canon, they are technically canon.
I'm not entirely sure what to make of this, but it suggests at least part of the company that produces ST considers the encyclopedia and tech manuals canon.Jan 22, 2005 wrote:Again. The encyclopedia is a reference to what has appeared on the show and in the movies. It's content is reporting on canon.
The tech manuals are written by the production staff about what has been established on the show and then expands a little.
The two novels were also written by a member of the production staff (the exec. producer in this case).