In the top 10, 2 are 1st-generation trust-fund babies (The Koch brothers), 7 are tech company founders, and 1 is self-directed investor. Certainly most of these enjoy great upper-middle-class opportunity and privelege, but these founders did not get their wealth from pedigree-appointed positions at Daddy's company after drinking their way through a Political Science degree.

Then come 3 more trust fund babies (The Walton kids), a self-made casino founder, and another tech company founder.