Dublin-born David McMurtry (78), who co-founded UK-headquartered precision engineering business Renishaw, is a billionaire thanks to his 36pc €1.17bn stake in the firm.
Living in greenest Gloucestershire, near Bristol, the inventor - who was born in Clontarf and went to Mount Temple school - holds more patents in his name than British billionaire and fellow inventor James Dyson. He has seen his paper fortune fall this year due to a fall in FTSE 250-listed Renishaw's share price of about 20pc. Nevertheless, he picked up a €17.9m dividend last year, and has banked over €100m in pay and dividends since 2009.
Renishaw, which employs about 5,000 people - including 260 in Swords - makes 3D metal printers, medical robots, and hi-tech components of laser altimeters and lidar. Its equipment is used by everyone from hospitals to major manufacturers such as Rolls-Royce and the Asian giants that are contracted to make smartphones for Samsung and Apple.
The firm began life in 1973, after McMurtry worked as a troubleshooter on the Concorde Olympus engine at Rolls-Royce, and where he met his co-founder, Welshman John Deer.
McMurtry and his wife are generous supporters of charities near where they live. He's also believed to support other causes here in Ireland anonymously. The company champions engineering, inventing, science and technology and is particularly keen to encourage young women to join the firm. Meanwhile, it also supported a Brunel museum and an aerospace museum in Bristol, which houses one of the last Concordes.
An eco-home that he designed and built in the Gloucestershire countryside cost €34m and featured in an episode of the BBC series, Sherlock. McMurtry, a fan of cars and motor racing, drives a top-of-the-range, souped-up Mini and also owns one of the cheapest Renault electric cars on the market. In 2016, he also invested in a small electric car startup close to where he lives, in which a group of young engineers, who have a background in Formula One and other top echelons of motorsport engineering, are working.