Marinus and Minna B Koster Foundation
Marinus and Minna B Koster Foundation is a private foundation focused on Philanthropy, Voluntarism & Grantmaking, based in POTOMAC FALLS, VA. IRS filing data is available from 2020 through 2024. As of 2024, the organization holds $7.0M in total assets. In 2024, it awarded 19 grants totaling $205K. Net investment income was $436K.
Financial Overview
From 2024 IRS Form 990-PF · View filing
Total Assets
$7.0M
+10.7% YoY
Annual Giving
$205K
+10.8% YoY
Grant Count
19
+11.8% YoY
Avg Grant Size
$11K
-0.9% YoY
About Marinus and Minna B Koster Foundation
Based on IRS filings
Marinus and Minna B Koster Foundation is a private foundation focused on Philanthropy, Voluntarism & Grantmaking, based in POTOMAC FALLS, VA. IRS filing data is available from 2020 through 2024. As of 2024, the organization holds $7.0M in total assets. In 2024, it awarded 19 grants totaling $205K. Net investment income was $436K.
Focus Areas
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Geographic Focus
Where this funder awards grants
Grant Distribution by State
Cities
Financial History
Multi-year comparison from IRS filings
| Metric | 2024 | 2023 | 2022 |
|---|---|---|---|
| Total Assets | $6,992,775 | $6,319,551 | $5,824,634 |
| Revenue | $463,944 | $212,480 | $289,287 |
| Expenses | $329,891 | $325,598 | $398,032 |
| Qualifying Distributions | $301,791 | $293,050 | $359,629 |
| Net Investment Income | $435,844 | $179,932 | $250,884 |
| Distributable Amount | $320,432 | $293,884 | $330,245 |
Giving Over Time
Total grant dollars and number of grants per year
Grant Insights
How this funder distributes its grants
Top Recipients
Top 10 recipients in 2024
Grant Size Distribution
94 grants across all recorded years
Open Grants
1 open opportunity from Marinus and Minna B Koster Foundation
Giving History
Grant recipients and amounts by year
No grants recorded for .
Leadership & Key People
Officers and directors from IRS filings
Compensation Overview
From 2024 IRS filing
From 2024 filing
| Name | Title | Hours | Compensation |
|---|---|---|---|
| ROSETTE M WILLS | PRESIDENT | 2 | $17,500 |
| BARBARA FREEDMAN | SECRETARY | 2 | $17,500 |
| MICHAEL T FLYNN | TREASURER | 2 | $17,500 |
| STERLING E SCROGGINS | ADVISOR | 1 | $3,500 |
| MIRIAM ISAACS | ADVISOR | 1 | $3,500 |
Subject Areas
Focus areas based on grantmaking activity
Data last updated April 2026. Sourced from IRS Form 990-PF filings.
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