William Todd Lithgow (1854–1908) was a Scottish ship-designer who became sole owner of an extremely successful shipbuilding company. For much of the 20th century its name was Lithgows, as it was developed further by William's sons Sir James Lithgow (1883–1952) and Henry Lithgow (1886–1948), and then by his grandson Sir William Lithgow (born 1934). By 1950 it was the largest private shipbuilding company in the world.