Ubisoft believes that a number of their game keys have been fraudulently obtained and resold and therefore, are currently deactivating them.
Third-party resellers such as Kinguin and G2A are known for selling game keys at a significantly reduced price compared to from the games’ official stores. The cheap region-unlocked keys are sold on to customers for them to activate in game clients and then play as if it were a normal key sold directly from the publisher.
This weekend saw many Uplay users writing on the Ubisoft forum to complain about the sudden removal of the titles (Far Cry 4 and Assassins Creed: Unity) from their libraries. As it seems, the users who have lost their games have reportedly purchased their keys from the third-party reseller, G2A.
Similar allegations against G2A arose last year in April when developer ‘Devolver Digital’ deactivated their keys bought from the store for Hotline Miami.