The present invention concerns a method for determining in a wireless cellular telecommunication network which device among a first device managing data associated to mobile terminals located in a first pool of cells and a second device managing data associated to mobile terminals located in a second pool of cells has to manage data associated to a mobile terminal. The first and second pools of cells have common cells and the mobile terminal is located in the first pool of cells. The first device managing data associated to the mobile terminal: receives a first message, from the mobile terminal located comprising a first list of at least one group of cells the mobile terminal moved through, determines if the cell in which the mobile terminal is located belongs to the second pool of cells, determines if the mobile terminal is going to leave the first pool of cells and/or will not leave the second pool of cells, from the first list and from the cell in which the mobile terminal is located, transfers a second message to the second device requesting the second device to manage data associated to the mobile terminal.