The phrase "undisclosed fee" means that the exact amount of money involved in a transaction or deal is not revealed or made known publicly. Full definition
Parkinson brought in Championship experience in all areas, with Aaron Wilbraham and Craig Noone joining for undisclosed fees from Bristol City and Cardiff City respectively. (htafc.com)
For coverage of another SEC enforcement action involving the undisclosed acceleration of monitoring fees, see «Blackstone Settles SEC Charges Over Undisclosed Fee Practices» (Oct. 22, 2015). (hflawreport.com)
Goodbye Sadio Mane, hello Nathan Redmond and Sofiane Boufal (signed, so we're told, for the delightfully weird - sounding «club record undisclosed fee»). (sbnation.com)