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Marilyn Simons & family
22%
Marilyn Simons & family has given an estimated 22% of total wealth: $10.3B in lifetime giving against $36.6B net worth.
- GiveRate
- 22%
- Lifetime giving
- $10.3B
- Net worth
- $36.6B net worth · Sept. 2026
- Status
- Estimated inputs
- Sources
- Forbes · Giving through Dec. 31, 2025
Forbes 400 · Net worth · Sept. 2026
The math
$10.3B ÷ ($10.3B + $36.6B) ≈ 22%. Lifetime giving through Dec. 31, 2025 (Forbes, Feb. 2026); net worth from the Sept. 2026 Forbes 400.
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