Aberdeen boss Mark McGhee has midfielder Stuart Duff he is free to leave Pittodrie.
Duff's contract expires this summer and he will not be offered an extension.
The former Dundee United midfielder spent time on loan at Inverness this season and could renew his relationship with newly-promoted side.
Italian defender Davide Grassi has been offered a short-term deal until December with his current contract due to expire this summer.
Meanwhile, 19-year-old defender Stirling Smith has inked a new deal to keep him at the club.