Limerick brothers John (26) and Patrick (28) have gone from being highly gifted students to paper billionaires in just a few short years. This year's Rich List continues to see them gallop up the rankings with valuations for their micro-payments firm, Stripe, racing ahead every few months.
A fundraising last November ensured they are each billionaires. It brought in $150m, giving the company a $9bn valuation. The brothers each own around 12pc of the business, giving them a net worth of over $1bn each.
The brothers have been making money since their teens — they sold their first company, Auctomatic, for $5m in 2008.
They both secured highly sought-after places in Harvard and MIT but dropped out to pursue their entrepreneurial leanings and set up Stripe in 2010. They discovered that businesses found arranging online payments difficult and they had an idea — simplifying online transactions. With initial backing from Tesla founder Elon Musk and Paypal's Peter Thiel, the company kept on growing.
Forbes has described the business as “a mobile payments phenomenon”. It employs over 600 people.