Oscar held by rogue art genre producer (9)
I believe the answer is:
generator
'producer' is the definition.
(I've seen this before)
'oscar held by rogue art genre' is the wordplay.
'oscar' becomes 'O' (phonetic alphabet: alpha, bravo, charlie etc.).
'held by' indicates putting letters inside.
'rogue' indicates anagramming the letters (letters go rogue).
'art'+'genre'='artgenre'
'artgenre' anagrammed gives 'generatr'.
'o' put into 'generatr' is 'GENERATOR'.
(Other definitions for generator that I've seen before include "It gives power" , "Power source" , "Dynamo or similar machine" , "Engine to produce electricity" , "juice maker" .)