Are SRPM spec files considered derivative source? (Score 1)

In reading the discussion, I have been wondering about modified source, source code distribution, etc. What I am not clear about is if a SRPM spec file comes under the GPL and other licenses? The spec file controls the build process, indicates what patches have been applied, what configure time flags have been used and how to packages. Is this a modification of the original source - or is this their own secret glue? This assumes the original developer did not provide their own spec file or Debian control files....