The Spitzer high resolution spectra of 72 Seyfert galaxies from the 12$\mu$m
Galaxy Sample are presented and discussed. The presence of starburst components
in these galaxies can be quantified by powerful mid-IR diagnostics tools (i.e.
11.25$\mu$m PAH feature equivalent width and the H$_2$ emission line
intensity), as well as the AGN dominance can be measured by specific fine
structure line ratios (e.g. [NeV]/[NeII], [NeV]/[SiII], etc.). The two types of
Seyfert galaxies do not show any statistical difference in our diagnostic
tools. However, the Seyfert 2's showing hidden Broad Line Regions in
spectro-polarimetric observations have on average an higher AGN dominance, a
weaker star formation component and a warmer [60 - 25] spectral index than
those without broad emission lines.