MUMBAI: Gujarat Ambuja Cements Ltd. (GACL) on Tuesday said it had sold 11 per cent stake in Ambuja Cement India Pvt Ltd (ACIL) to Swiss cement major Holcim for Rs. 526.50 crore. The company, which owns 33 per cent holding in ACIL, has exercised its put option for 11 per cent stake and sold 9.53 crore shares to Holcim.