Wealth
As of 2013, Kellner owned 98.93% of the PPF investment and financial group.
In 2006, he was first time listed in Forbes list of billionaires with estimated net worth at US$3 billion and as 224th wealthiest man in the world. In 2007, he was 119th with US$6 billion; in 2008 he was 91st with US$9.3 billion. In 2009, he was 76th with US$6 billion. In 2010 he was 89th with US$7.6 billion; according to the Czech weekly Týden, the estimates were lower, however, approx. US$4 billion.
In 2015, Kellner ranked #137 on the Forbes list with an estimated wealth of US$9.2 billion (2015). In August 2016, he ranked #102 with US$11.4 billion, making him the wealthiest person in the Czech Republic. In 2018, Kellner ranked #88, with US$15.5 billion. In 2020 he ranked #68 with US$14.9 billion. In October 2020, Czech Forbes listed him as the richest person in the Czech Republic with net worth 293 billion CZK (around US$13 billion at the time).
In 2010 he bought a Boeing 737-700 BBJ1 as his business airplane. It was registered P4-NGK and was operated by ABS Jets. After his death in 2021, the 737 was used to repatriate his body back to the Czech Republic. His home was in an extensive residence, in the village of Podkozí near Prague. He also owned a number of other properties in several countries. He possessed one of the largest collections of photographs taken by Josef Sudek who was best known for his neo-romantic photography.
He was an avid fan of the Jára Cimrman plays, as a result, PPF Group is a sponsor of Jára Cimrman Theatre since 1999.