Complex sentence: Due to their very successful operations, in 1948 Farrell was forced to reduce his interest from 92% to 10% by the British colonial government which would not allow an American citizen to own the controlling interest of a British-registered company.
Split into simpler sentences: Due to their very successful operations, in 1948 Farrell was forced to reduce his interest from 92% to 10% by the British colonial government. This was because they would not allow an American citizen to own the controlling interest of a British-registered company.