Five French television companies are investing $490m to launch a digital television service on Eut?elsat satellites by the end of the year, competing on the French lan?guage market with Canalsatellite from Canal Plus and its major shareholder Havas SA, which will begin broadcasting on April 27 using Astra satellites. Talks are still under way on a potential agreement over a common decoder to unscramble the satellite signals. Broadcaster TF1 said the alliance wants an open system, unlike Canal Plus, which is insisting on a prop?rietary decoder. TF1 is 38%-owned by conglomerate Bouygues SA and state-owned public broadcaster France Television who each have a 25% stake in the new alliance. Compagn?ie Luxembourgeoise de Telediffusion SA will take a 20% stake and diversified conglomerate with cable operator Lyonnaise des Eaux SA taking 10%. M6, in which both Lyonnaise and CLT have big stakes, will take a 20% holding. Havas raised doubts the alliance could succeed, however, noting that CLT had not yet signed.