Swiss major Holcim has increased its stake in Ambuja Cements by around 4 per cent in the last couple of months to over 50 per cent through open market transactions. It has been noticed that ever since Holcim picked up stake in Ambuja Cements, it has been increasing its holdings in the firm. And during the last couple of months, Holcim has picked up an additional 4 per cent stake in Ambuja taking its total equity holding to over 50 per cent. The shares, thus accumulated were bought through open market transactions. The global cement major Holcim had in 2006 acquired the management control of Ambuja Cements, founded by Narotam Sekhsaria in 1983 with a partner, Suresh Neotia. Gradually, it increased its stake to 46 per cent towards the end of 2007. Holcim also controls ACC. ACC and Ambuja Cements together have 52 million tonne per annum or around 20 per cent of India's total cement installed capacity. ACC has 27 million tonne per annum and Ambuja Cements 25 million tonne per annum capacity in 2010. Work is on at ACC to increase the capacity to 30 million tonne per annum by the middle of the current year and at Ambuja Cements to 27 million tonne per annum within 2011.