Non-threatening party line adopted by French company (6)
I believe the answer is:
docile
'non-threatening' is the definition.
(docile can mean non-threatening or subservient)
'party line adopted by french company' is the wordplay.
'party' becomes 'do' (do is a kind of party).
'line' becomes 'l' (used when specifying particular lines from a poem).
'adopted by' indicates putting letters inside (I've seen this in other clues).
'french company' becomes 'cie' (abbreviation of the french 'compagnie').
'l' inserted into 'cie' is 'cile'.
'do'+'cile'='DOCILE'
(Other definitions for docile that I've seen before include "Coiled in obedient way" , "Gentle and tractable" , "Gentle and teachable" , "Willing to obey, not aggressive" , "Meek and biddable" .)