Portsmouth and agent Willie McKay have been charged by the Football Association with breaches of rules in relation to the transfer of Benjani Mwaruwari to and from the club.
Under the FA's football agents regulations, agents are prohibited from acting for two different clubs in two consecutive transactions involving the same player.
Clubs are not allowed to use the services of an agent in such circumstances, the FA stated.
It is alleged that McKay acted on behalf of Auxerre in respect of the transfer of Benjani from Auxerre to Portsmouth in January 2006.
He is then alleged to have acted for Portsmouth in Benjani's transfer from Portsmouth to Manchester City in January this year, the subsequent completed transaction involving the player.
Both parties have until August 29 to respond to the charges.