Jack's predecessor receiving endorsement of minimal value (5)
I believe the answer is:
token
'of minimal value' is the definition.
'jack's predecessor receiving endorsement' is the wordplay.
'jack's predecessor' becomes 'ten' (tens come before jacks in playing card suits).
'receiving' is an insertion indicator.
'endorsement' becomes 'ok' (OK is an example).
'ten' enclosing 'ok' is 'TOKEN'.
(Other definitions for token that I've seen before include "Representative item" , "Privately issued coin or voucher" , "signal" , "Shopping voucher" , "without meaning it" .)