What the informer did when paid the money? (7)
I believe the answer is:
shopped
'paid the money?' is the definition.
The definition and answer can be both to do with ownership as well as being past participle verbs.
Perhaps there's an association between them I don't understand?
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for shopped that I've seen before include "Bought goods or slangily informed on" , "Bought goods or gave away information about someone" .)