Chennai is home to three large national level commercial banks[52][53][54] and many state level co-operative banks, finance and insurance companies. Some of India's well-known healthcare institutions such as Apollo Hospitals (the largest private healthcare provider in Asia),[55] Sankara Nethralaya and Sri Ramachandra Medical Centre are based in the city, making it one of the preferred destinations for medical tourists from across the globe.[56] Telecom giants Ericsson and Alcatel-Lucent, pharmaceuticals giant Pfizer and chemicals giant Dow Chemicals have research and development facilities in Chennai. TICEL bio-tech park[57] and Golden Jubilee bio-tech park[58] at Siruseri house biotechnology companies and laboratories. Chennai has a fully computerised stock exchange called the Madras Stock Exchange.
