The court had made a snap decision in January to block the sale, after Orascom appealed a market regulator ruling that France Telecom could offer to buy all outstanding shares in Mobinil for 245 Egyptian pounds ($44.63) each.
"After this court ruling we will study the decision and the designated authorities will decide if we will appeal it or not," Ahmed Masrafi, a lawyer from the Egyptian Financial Supervisory Authority, told Reuters.
Three tender offers
An international arbitration had earlier ruled that Orascom should sell its 28.75 per cent stake in the holding company to the French firm for 273 pounds, a decision Orascom and Egyptian authorities said forced an obligatory offer for the entire company.
France Telecom had made three tender offers, all at prices below 273 pounds, which were rejected by the regulator before the fourth bid at 245 pounds was accepted.
The two firms jointly own the holding company that controls the firm, while Orascom also holds a 20 per cent direct stake.
"This decision is a big victory for Orascom and it will ensure that we continue to provide quality services to the Egyptian telecom market," Orascom lawyer Osman Mowafi said.
France Telecom said that they did not wish to comment on the matter.