Dunderland Iron Ore Company, Ltd

This company was incorporated in London on April 25, 1902, to acquire and work deposits of iron ore, using Edison's ore processing technologies. Originally controlled by the Edison Ore Milling Syndicate, Ltd., it erected an ore concentration plant near Mo, in the Dunderland region of Norway. The company went into receivership during 1908, then reemerged with a reconstituted board in 1910. By 1914 it was known as the New Dunderland Iron Ore Company, Ltd.

Edison Iron Concentrating Company.

This company was incorporated on January 7, 1889, to engage in ore processing. In December 1890 its mill at Humboldt, Michigan, was destroyed by fire. In 1902 the company was dissolved.

Edison Ore Milling Company, Ltd.

This company was organized on December 9, 1879, to extract iron, gold, and other metals from ores. From September 1881 until January 1883 it operated a plant at Quonocontaug, Rhode Island. After its reorganization in 1887, it provided financial support for Edison's ore separation and concentration experiments in return for control of his related patents. The company was officially dissolved on April 2, 1924.

Edison Ore-Milling Syndicate, Ltd.

The Edison Ore Milling Syndicate, Ltd., was organized in London on February 24, 1898, to exploit Edison's ore milling patents in all countries except the United States and Canada. The company used Edison's patents and ore milling designs when developing iron deposits in the Dunderland River valley, near Mo, Norway. It also tried to promote the use of Edison's ore milling technologies in diamond crushing, gold separation, and cement manufacturing. In August 1909 the company entered liquidation.