ClassNK 
Nippon Kaiji Kyokai, known as ClassNK or NK, has earned a high reputation for its long-standing dedication to safeguarding life and property at sea and preventing marine pollution through the establishment of universally recognized standards for the design, construction and maintenance of ships and other marine structures.
http://www.classnk.or.jp/ABS
American Bureau of Shipping, classification society.
http://www.eagle.org/
Bureau Veritas
French classification society.
http://www.bureauveritas.com/
GL- Germanischer Lloyd
German classification society.
http://www.germanlloyd.de/
Korean Register of Shipping
The Korean Register of Shipping (KR) is a non-profit ship classification society established in June 1960. It is dedicated to working toward the goal of safe ships and clean oceans through promoting technology and human resource development related to shipping, shipbuilding, and industrial services.
http://www.krs.co.kr/
RINA
Registro Italiano Navale, Italian classification society.
http://www.rina.it/
International Naval Surveys Bureau
A non-governmental classification society authorised by St. Vincent and the Grenadines.
http://www.insb.gr
Lloyd's Register
UK based classification society.
http://www.lr.org/
DNV: Det Norske Veritas
Norwegian classification society, also provides certification of management systems, products and personnel to the landbased and offshore industries. It is a worldwide firm.
http://www.dnv.com/
Indian Register of Shipping
A classification society established in 1975, with a quality management system complying with the requirements of International Association of Classification Societies.
http://www.irclass.org/
