the company was formed in 1902 as the tabulator limited, after robert porter obtained the rights to sell herman hollerith's patented machines from the us tabulating machine company (later to become ibm). by 1909, the company had been renamed the "british tabulating machine company limited". in 1920, the company moved from london to letchworth, hertfordshire; it was also at this point that it started manufacturing its own machines, rather than simply reselling hollerith equipment.