"The board, following thorough examination, unanimously decided not to pursue the unsolicited offer by the Altice group," Bouygues said in a statement, citing "significant execution risks" related to competition laws in seeking to merge two large rivals.
The decision comes after Monday's purchase offer by Altice for a reported 10 billion euros ($11.3 billion). The bid sought to combine Bouygues' mobile, internet, and fixed phone businesses with those of Altice affiliate Numericable-SFR, and propel the merged group into France's top spot ahead of leader Orange.
The move met the opposition of France's leftist government, which voiced concerns about employment threats and higher consumer prices should the nation's sector consolidate from four to three players, as has happened in many other European markets.
In addition to citing competition concerns in rejecting the Altice offer, Bouygues also said its "strong and lasting competitive advantage" derived from its range of mobile frequencies and 4G network left it capable of expanding its business on its own.
The rejection was a setback for Altice's acquisition-hungry owner, Franco-Israeli tycoon Patrick Drahi, who has undertaken a spree of impressive, debt-financed telecom and media acquisitions in Europe and the US since 2014, when he purchased SFR and later merged it with cable operator Numericable.