Big Four (companies)

Big Four can refer to several sets of four dominant companies that constitute oligopolies in their respective fields and regions:Railroads The Big Four British railway companies were four largest railway companies in the United Kingdom in the period 1923-1947.The Big Four Irish railway companies in the late 19th and early 20th centuries were Great Southern & Western Railway, Midland Great Western Railway, Dublin & South Eastern Railway and Great Northern Railway."The Big Four" was the collective name given to four railroad magnates in the western U.S.: Collis P. Huntington, Leland Stanford, Mark Hopkins, and Charles Crocker.
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