Tally up the lost estate taxes from the superwealthy who passed away this year, and that's about $9.9 billion that Uncle Sam missed out on.
Co-founder of Enterprise Products Partners (gas and oil pipelines)
Passed away: March 28, 2010
Wealth-X (Est.): $10 billion*
Potential tax uncollected: $4.5 billion**
NEXT: John Kluge
Last updated December 22 2010: 5:34 AM ET
*Net worth figures from Wealth-X. **Assuming tax liability hasn't been reduced by trusts and charitable deductions. N.A.: not available