How bout Ross Perot. I don’t see him on this thread or on the Forbes site either. Though he was fairly rich…[sub] ‘member him sayin’ ‘Don worry bout me, got 4 billyun in da bank…’
JImmy Stewart in “It’s a Wonderful LIfe.”
I heard his brother say so at the end of the movie. 
What about the Rothschilds?
Don’t they own most of the big banks? And aren’t their assets kept secret?
In this day and age of multi-billionaires I dont think Ross Perrot is a major player anymore. Sure compared to you an me he make more in interest than we’ll ever see in our life time but when you put him in a league with Arab oilmen (sorry for the generalization) he’s a small time player comparatively
I know the OP ask about men (women too of course) but to slightly hijack my own thread what about organizations. I am going to tread on dangerous ground and this is not meant to be or start a flame (disclaimer done).
What about the Roman Catholic Church ? I just think about the property they own in a city like Montreal. The RCC has about 90 - 100 (rought estimate) ornate stone churces that would probably average out to about 40 million EACH to rebuild (we are talking replacemetn value here).
Simple math warning!
90 x 40 000 000 = $ 3 600 000 000
Thats 3.6 Billion in value just in a Major Canadian City…Think globaly what are they REALLY worth ??
Need to read around, Patricinus Scriblerus. See Tomndebb’s answer here. 
'sides, I don’t know if your allowed to hijack your own OP.
OP asks about a man.
A simple web search with the exact OP question turns up exciting data on this subject whose answer probably changes almost daily…plus, I think it’s a moot point because converting from the currency of one country to another to determine wealth is rather pointless.
I always thought it was the Sultan of Brunei