Overturned litigant film custodian issuing notice (6)
I believe the answer is:
remark
'notice' is the definition.
(remark is a kind of notice)
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for remark that I've seen before include "Notice; happen to say" , "Mention - observe" , "what someone says?" , "Incidental observation" , "Comment, observation" .)