Tata Consultancy Services Limited (TCS) is an Indian multinational information technology (IT) service, consulting and business solutions company headquartered in Mumbai, Maharashtra. It is a subsidiary of the Tata Group and operates in 46 countries. TCS is one of the largest Indian companies by market capitalization ($80 billion). TCS is now placed among the â€˜Big 4â€™ most valuable IT services brands worldwide. In 2015, TCS is ranked 64th overall in the Forbes World's Most Innovative Companies ranking, making it both the highest-ranked IT services company and the first Indian company. It is the world's 10th largest IT services provider, measured by the revenues. As of December 2015, it is ranked 10th on the Fortune India 500 list.