NetJets, a subsidiary of Berkshire Hathaway, offers fractional ownership and rental of private business jets. Formerly called Executive Jet Aviation, NetJets Inc. was founded in 1964.It was the first private business jet charter and aircraft management company in the world.etJets, a subsidiary of Berkshire Hathaway, offers fractional ownership and rental of private business jets. Formerly called Executive Jet Aviation, NetJets Inc. was founded in 1964.