The Robert and Diane Weissman Foundation
The Robert and Diane Weissman Foundation is a private foundation, based in Los Altos, CA. IRS filing data is available from 2021 through 2025. As of 2025, the organization holds $1.7M in total assets. In 2025, it awarded 4 grants totaling $3K. Net investment income was $456K.
The Robert and Diane Weissman Foundation at a glance
In short: The Robert and Diane Weissman Foundation gave $3K across 4 grants in 2025 (avg $700), mostly in Arizona. Source: 2025 IRS Form 990-PF.
- Annual giving (2025)
- $2,800
- -62.7% vs 2024
- Grants made (2025)
- 4
- +33.3% vs 2024
- Average grant
- $700
- -72.0% vs 2024
- Median grant
- $875
- Total assets
- $1,737,656
- +25.4% vs 2024
- Primary geography
- Arizona (64% of itemized 2025 grant dollars)
- Latest 990 filing
- Form 990-PF, 2025 View filing
Data from IRS Form 990-PF, 2025; updated September 2026.
Who The Robert and Diane Weissman Foundation funds
How this funder distributes its grants
Top Recipients
Top 4 recipients in 2025
The largest 2025 recipient was tiger Mountain Foundation ($1K). Together the top 4 received $3K.
Grant Size Distribution
8 grants across all recorded years
The most common grant size was under $50K: 8 grants of 8 (100%).
Geographic Focus
Where this funder awards grants
Grant Distribution by State
Share of 2025 grant dollars across all 4 itemized grants.
States
Cities
Giving History
Giving Over Time
Total grant dollars and number of grants per year
From 2021 to 2025, annual grant giving ranged from $1K (2021) to $8K (2024). In 2025 it made 4 grants totaling $3K.
Grants by year
Grant recipients and amounts by year
| Recipient | Purpose | Amount |
|---|---|---|
| tiger Mountain Foundation Phoenix, AZ | Support of Community Garden | $1,000 |
| Daughters of Cambodia | Program support | $1,000 |
| Golden Eagle Foundation Fountain Hills, AZ | Support of programs to support classroom teachers | $750 |
| Courtneys Place Scottsdale, AZ | Support of programs | $50 |
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Financial History
Multi-year comparison from IRS filings
| Filing year | Total Assets | Revenue | Expenses | Grants paid | Grants | Qualifying Distributions | Net Investment Income |
|---|---|---|---|---|---|---|---|
| 2025 | $1,737,656 | $465,686 | $113,227 | $2,800 | 4 | $103,128 | $455,587 |
| 2024 | $1,385,195 | $64,420 | $92,581 | $7,500 | 3 | $87,455 | $59,294 |
| 2023 | $1,413,357 | $26,344 | $75,237 | — | — | $66,370 | $17,526 |
| 2022 | $1,773,199 | $362,924 | $53,903 | — | — | $47,633 | $174,208 |
| 2021 | $1,464,037 | $149,296 | $69,189 | $1,000 | 1 | — | $88,674 |
Leadership & Key People
Officers and directors from IRS filings
The Robert and Diane Weissman Foundation is led by Robert H. Weissman, President & Director on every filing since 2021; none of the 2 officers listed in 2025 report compensation.
Officers on the 2025 filing
Robert H. Weissman
President & Director
On filings since 2021
12 hrs/week
No compensation reported
Diane E. Weissman
Treasurer Secretary & Director
Treasurersecretary & Director → Treasurer Secretary & Director, 2023
On filings since 2021
4 hrs/week
No compensation reported
Data from IRS Form 990 filings, 2021–2025. "On filings since" is the earliest filing we hold that lists the person; hours are average hours per week as reported.
Frequently asked questions about The Robert and Diane Weissman Foundation
How much does The Robert and Diane Weissman Foundation give each year?
The Robert and Diane Weissman Foundation gave $3K across 4 grants in 2025, according to its 2025 IRS Form 990-PF. In 2024 it gave $8K across 3 grants.
What is The Robert and Diane Weissman Foundation's typical grant size?
The Robert and Diane Weissman Foundation's median grant in 2025 was $875, and its average grant was $700, across 4 grants on its 2025 IRS Form 990-PF.
Where does The Robert and Diane Weissman Foundation give grants?
The Robert and Diane Weissman Foundation gives mostly in Arizona: 64% of the grant dollars itemized on its 2025 IRS Form 990-PF went to recipients there.
Does The Robert and Diane Weissman Foundation give general operating support?
Not in 2025: none of the 4 grants with a stated purpose on The Robert and Diane Weissman Foundation's 2025 IRS Form 990-PF were described as general or operating support.
How large is The Robert and Diane Weissman Foundation?
The Robert and Diane Weissman Foundation reported $1.7M in total assets on its 2025 IRS Form 990-PF. Its revenue that year was $466K.
What is The Robert and Diane Weissman Foundation's EIN?
The Robert and Diane Weissman Foundation's EIN (Employer Identification Number) is 77-0560173. IRS Form 990 filing data is available on this page for 2021–2025.
Data last updated September 2026. Sourced from IRS Form 990-PF filings.
Data update history
(1)
When this profile's IRS filing data changed on Grantable
- IRS filings on file for fiscal years 2021–2025
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