Leidos Holdings, Inc. is an American defense, aviation, information technology and biomedical research company headquartered in Reston, Virginia. Formed in 2013 when Science Applications International Corporation (SAIC) split into two companies, Leidos provides scientific, engineering, systems integration and technical services primarily to U.S. government agencies across the defense, intelligence, civil and health markets. It is publicly traded on the NYSE under the ticker LDOS and employs roughly 47,000 people.