One of the country's best-known and most successful businessmen, Michael Smurfit (81) turned a small cardboard box firm into the global giant that became Smurfit Kappa.
In 2002, he earned €230m for his 7.5pc stake when US firm Madison Dearborn acquired it for €3.8bn. He later spent €55m to buy 4.29pc of the private company back before it returned to the stock market in 2007, and he later made money again selling that stake. The family are believed to still retain a tiny stake, less than 1pc.
In 2016, he banked an estimated €62m from his stake in his brother Dermot's firm Powerflute, which was bought by a familiar name: Madison Dearborn. He also invests in start-ups, including nephew Dermot Jr's gambling tech firm GAN and Offaly-based farm tech firm MooCall. He has also invested in cancer treatment firm Inflection Biosciences, while past investments include postal software firm Escher Group, telecoms firm Perlico, CNG Travel and Skillpages, the latter two of which lost money.
For his 80th birthday he brought 100 close friends, family and VIPs on a superyacht voyage lasting a week from Venice to Corfu via Dubrovnik, Hvar and Montenegro. Another voyage is planned for his 85th.
Among his most prized possessions are a €60m yacht called the Lady Ann Magee, an art collection that includes top pieces by Louis LeBrocquy and Jack B Yeats worth a similar amount, and several properties, including a stud farm in Kildare where he breeds horses.
The Monaco-based golfing fan and bon viveur paid €115m to buy The K Club with developer Gerry Gannon during the boom, but later won a battle to take control of it from Nama by buying Gannon's stake. Its last accounts show it owes creditors €76m, most of which is believed to be owed to Smurfit.
A palatial 10-bedroom Spanish property in Marbella, Casa Loriana, has languished on the market for a number of years, and comes with a private beach and a mooring for a yacht, with asking prices having ranged from between €50m and €80m.