(Telecompaper) French conglomerate Bouygues did not only improve the cash element of its takeover bid for Vivendi's operator SFR, but also included a break up-up fee of between EUR 500 million and EUR 1 billion if the competition authority blocked the operation, a person familiar with the matter told La Tribune newspaper. The break-up fee would also be used if the authority imposed remedies that offset the estimated EUR 10 billion of synergies to be gained from the acquisition. Another source close to the discussions confirmed the existence of a break-up fee, but said it amounted to a maximum of EUR 500 million. Bouygues, which is offering Vivendi EUR 13.15 billion plus a 21 percent stake for Vivendi in the merged Bouygues Telecom-SFR, would not comment on the matter. Vivendi is in exclusive negotiations with cable operator Numericable's parent company, Altice, until 4 April about its rival bid of EUR 11.75 billion plus a 32 percent share for Vivendi in a combined Numericable-SFR. Separately, sources told the Wall Street Journal that Numericable does not plan to raise the value of its bid.