Both businesses continued to be family run, and they overcame difficulties with supplies in World War I. By 1918 they together accounted for a third of British sugar production. Although competitors, the two companies chose to amalgamate in order to maintain their power in the market, and the government sanctioned the merger even though it gave the company such a dominant position. The new company extended operations by taking over a number of smaller producers in subsequent years. In 1923 Tate & Lyle accounted for half of the refined sugar in Britain; by 1938 business acquisitions meant that it controlled three-quarters of British refining capacity. The new company also took an interest in producing its own sugar for refining by investing in a beet sugar factory in 1925. In 1937, following the establishment of the British Sugar Corporation that had a monopoly in beet production, Tate & Lyle bought cane plantations in Jamaica and Trinidad. Thus, on the eve of World War II, the company had a virtual monopoly in refining and was a major supplier of raw cane sugar.