Exploit legal document (4)

I believe the answer is:

deed

I believe this clue is a double definition.

'exploit' is the first definition.
(I've seen this before)

'legal document' is the second definition.
(deed is a kind of legal document)

(Other definitions for deed that I've seen before include "Conscious act" , "documentary evidence" , "Something done" , "Feat" , "A conscious action" .)

I've seen this clue in The Telegraph and The Guardian.

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