Have gangs succeeded? (7)

I believe the answer is:

possess

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'have' is the definition.
(I know that have can be written as possess)

I don't understand the remainder of the clue.

(Other definitions for possess that I've seen before include "Have as one's own" , "Have - control" , "influence" , "Own, keep" , "Consume" .)

I've seen this clue in The Telegraph.

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