Citigroup is an American transnational financial services corporation established in 1812 and headquartered in New York. Citigroup is the fourth largest of the American banks and a systematically important bank for the U.S. and world economy. Citigroup’s revenue is currently more than $71.5 billion. Citibank is a part of Citigroup that specializes on consumer financial services. Some major Citibank branches are the American and Mexican branches, but Citi also has its branches in Russia, India, the UAE and some other countries. Citigroup’s blockchain research and development were some of the first in the banking and financial services sector. Citi and Nasdaq announced an agreement that implemented blockchain in global banking in May 2017. This agreement authorizes Citi to transfer funds into Nasdaq’s blockchain platform that is used for buying and selling shares of private companies.