This tool is based on a brief [1] which is basically an update of a study [2] they released in 2011. Neither goes into much detail on methodology but the origin

This tool is based on a brief [1] which is basically an update of a study [2] they released in 2011. Neither goes into much detail on methodology but the original study at least has an appendix identifying the immigrant founder(s). [1] https://research.newamericaneconomy.org/report/new-american-fortune-500-in-2018-the-entrepreneurial-legacy-of-immigrants-and-their-children/ https://research.newamericaneconomy.org/report/new-american-... [2] https://www.newamericaneconomy.org/wp-content/uploads/2013/07/new-american-fortune-500-june-2011.pdf https://www.newamericaneconomy.org/wp-content/uploads/2013/0...