Far Cry 4
Far Cry 4 was Ubisoft's biggest success of 2014.Ubisoft

Ubisoft is reportedly deleting copies of Far Cry 4 from its Uplay service in an effort to crackdown on third-party digital retailers.

An open letter penned to Ubisoft on its support forum claims that copies of the game bought via websites G2Play and G2A are being removed without warning.

Ubisoft is now apparently telling affected users to contact the retailers directly.

G2Play's owners 7 Entertainment have come under fire before for re-selling Surgeon Simulator 2013 keys via its website and sister sites Fast2Play and Kinguin. Henrique Olifiers of Surgeon Simulator developers Bossa Studios said: "It's 7 Entertainment itself selling it directly, not 'users' nor 'marketplace'. And they're doing so without our authorisation."

The company has also been criticised for re-selling keys obtained through Humble Bundle, a pay-what-you-want service that donates money raised through sales to charity.

Last year Devolver Digital also cracked down on G2A, stating the following through their Twitter account.