The G Harold & Leila Y Mathers
The G. Harold & Leila Y. Mathers Foundation is a private foundation headquartered in Rye Brook, New York. Established in 1983, it supports basic scientific research with the potential to advance knowledge in the life sciences and improve human health.
The G Harold & Leila Y Mathers at a glance
In short: The G Harold & Leila Y Mathers gave $17.3M across 103 grants in 2024 (avg $168K), top state Massachusetts. 14% of 2024 grantees were new. Source: 2024 IRS Form 990-PF.
- Annual giving (2024)
- $17,273,778
- +4.9% vs 2023
- Grants made (2024)
- 103
- +35.5% vs 2023
- Average grant
- $167,707
- -22.6% vs 2023
- Median grant
- $225,000
- Total assets
- $107,899,647
- +8.0% vs 2023
- New grantees (estimate)
- 14% first-time grantees (7 of 51, 2024)
- Primary geography
- Massachusetts (37% of itemized 2024 grant dollars)
- Latest 990 filing
- Form 990-PF, 2024 View filing
Data from IRS Form 990-PF, 2024; updated October 2026. New grantees are estimated by matching recipient names across years (methodology).
How to apply to The G Harold & Leila Y Mathers
- How to Apply
-
Applications go through the foundation’s online portal in a formal two-step process. Institutional nomination is required before an LOI; registration and nominations must be completed at least two weeks before the cycle’s due date. The LOI includes a project summary, related work, and a three-year budget. Approved LOIs may be invited to submit a formal proposal, which must include a project summary, scientific aims, and a budget justification. Grants are typically awarded within five to six months of LOI submission. The foundation does not make grants to individuals or private foundations and rarely funds periods longer than three years.
- Review Cycle
- Applications are reviewed on a trimester basis; applicants should consult the foundation’s current cycle information for due dates.
- Deadline
- Applications are reviewed on a trimester basis; applicants should consult the foundation’s current cycle information…
- Contact
Application contact: Zachary S Handelman Dir-Operations
Mailing address: 800 Westchester Avenue Ste N-503, Rye Brook, NY 10573-1373
Phone: (914) 242-0465
Website: https://mathersfoundation.org
Application details from Grantable's research on the foundation's public materials; confirm on its website before applying.
Open Grants
1 open opportunity from The G Harold & Leila Y Mathers
Who The G Harold & Leila Y Mathers funds
How this funder distributes its grants
Top Recipients
Top 10 recipients in 2024
The largest 2024 recipient was Dana-Farber Cancer Institute ($1.9M across 10 grants). Together the top 10 received $9.8M.
Grant Size Distribution
432 grants across all recorded years
The most common grant size was in the $100–250K range: 224 grants of 432 (52%).
Geographic Focus
Where this funder awards grants
The foundation’s eligibility guidance limits institutional applicants to those based in the United States. In 2024, Massachusetts received 37% of grant dollars, New York 20%, California 18%, Ohio 7%, and Connecticut 5%.
Grant Distribution by State
Share of 2024 grant dollars across all 103 itemized grants.
States
Cities
Is The G Harold & Leila Y Mathers open to new grantees?
14%
first-time grantees, 2024
In 2024, 7 of 51 grantees (14%) were first-time recipients. First grants averaged $172K; repeat grants $365K. How we count
Medians: $234K first-time, $233K repeat.
- 86% of 2024 grantees were also funded in 2023. Method
- Giving held roughly steady from 2021 to 2024 (+15%). Method
- In 2024 it paid out 96% of its IRS minimum distribution (the 5% rule). Foundations have until the end of the next year to meet it. Method
Estimate from itemized grant lists in IRS Form 990-PF filings (2020–2024). Recipient names are matched across years, so a renamed or misspelled grantee can look new; grants to individuals are left out. Methodology.
Giving History
Giving Over Time
Total grant dollars and number of grants per year
From 2020 to 2024, annual grant giving ranged from $13.1M (2020) to $17.3M (2024). In 2024 it made 103 grants totaling $17.3M.
Grants by year
Grant recipients and amounts by year
| Recipient | Purpose | Amount |
|---|---|---|
| Rockefeller University New York, NY | Research Project | $277,200 |
| Massachusetts Institute of Technology Boston, MA | Research Project | $270,000 |
| Yale University New Haven, CT | Research Project | $268,534 |
| California Institute of Technology Pasadena, CA | Research Project | $264,398 |
| Leland Stanford Junior University Stanford, CA | Research Project | $259,200 |
| Children's Hospital Corp (Boston Children's Hospital) Boston, MA | Research Project | $256,184 |
| Children's Hospital Corp (Boston Children's Hospital) Boston, MA | Research Project | $253,000 |
| Vanderbilt University Medical Center Nashville, TN | Research Project | $252,199 |
| Case Western Reserve University Cleveland, OH | Research Project | $250,000 |
| Cleveland Clinic Foundation Cleveland, OH | Research Project | $250,000 |
Ready to take the next step with The G Harold & Leila Y Mathers?
Financial History
Multi-year comparison from IRS filings
| Filing year | Total Assets | Revenue | Expenses | Grants paid | Grants | Qualifying Distributions | Net Investment Income | Distributable Amount |
|---|---|---|---|---|---|---|---|---|
| 2024 | $107,899,647 | $29,243,446 | $18,497,648 | $17,273,778 | 103 | $18,623,245 | $26,786,487 | $19,360,324 |
| 2023 | $99,932,556 | $23,491,261 | $16,295,854 | $16,465,249 | 76 | $17,624,210 | $21,255,933 | $16,887,562 |
| 2022 | $96,422,457 | $20,904,966 | $23,366,307 | $17,144,359 | 87 | $18,303,915 | $18,749,568 | $17,183,059 |
| 2021 | $96,045,942 | $16,941,265 | $18,422,730 | $15,066,168 | 79 | $16,251,360 | $14,992,665 | $17,017,883 |
| 2020 | $97,620,736 | $15,655,700 | $16,461,723 | $13,090,544 | 87 | — | $13,741,609 | $14,390,329 |
Under IRS private-foundation payout rules, The G Harold & Leila Y Mathers reported a distributable amount of $19.4M for 2024 — the minimum it must pay out in qualifying distributions.
Research compiled by Grantable AI from public sources. Last updated September 2026.
Mission & Focus Areas
The foundation’s mission is to advance knowledge in the life sciences by funding bold, basic scientific research with the potential to transform human health. Its stated areas of support include immunology, microbiome, structural biology, cellular physiology, cancer biology, genetics, genomics, microbiology and infectious diseases, stem cell biology, and neuroscience. The foundation identifies clinical trials and drug discovery, vaccine development, plant biology, and several other areas as ineligible; its lists may be subject to change or interpretation by the board.
Eligible applicants include medical research universities and scientific institutions that are nonprofit organizations, as well as principal investigators with fully equipped labs and collaborative projects with other U.S.-based organizations. The foundation prefers applicants to hold 501(c)(3) status. Its 2024 filing states that grants are made to tax-exempt organizations that are not private foundations, or to specified governmental entities or state colleges and universities; it does not make grants to individuals.
Grantee examples include universities and research institutions. MIT describes its mission as advancing knowledge and educating students in science and other fields; the Whitehead Institute says it forges new scientific frontiers, including in genetics and genomics. Case Western Reserve University describes itself as a research-oriented university with strengths including health, engineering, arts and sciences, and law, management, and social work.
Grantmaking
In 2024, the foundation reported 103 grants totaling $17,273,778. Individual grants ranged from $1,000 to $277,200, with a median of $225,000. The listed largest awards were generally designated for research projects.
Among the 2024 grants were $277,200 to Rockefeller University, $270,000 to MIT, $268,534 to Yale University, and $264,398 to the California Institute of Technology. Other recipients included Boston Children’s Hospital, Vanderbilt University Medical Center, Case Western Reserve University, Cleveland Clinic Foundation, and Columbia University.
Leadership & Key People
Leadership team and compensation from IRS filings
Officers and directors listed on the 2024 filing are Richard Handelman (president/director), Howard Chester (secretary/director), Zachary Handelman (treasurer, vice president, and director of operations), David Boyle (director), Judy Herman (director), Peter Gottlieb (director), and Scott Handelman (director).
The G Harold & Leila Y Mathers is led by Richard Handelman, President & Director on every filing since 2020; all 7 officers listed in 2024 are compensated.
Officers on the 2024 filing
Richard Handelman
President & Director
On filings since 2020
4 hrs/week
$45K (2020) → $50K (2024)
David Boyle
Director
Secretary & Director → Director, 2024
On filings since 2020
2 hrs/week
$45K (2020) → $50K (2024)
Judy Herman
Director
On filings since 2020
2 hrs/week
$45K (2020) → $50K (2024)
Peter Gottlieb
Director
On filings since 2020
2 hrs/week
$45K (2020) → $45K (2024)
Howard Chester
Secretary & Director
Director → Director & Executive Director, 2022
Director & Executive Director → Secretary & Director, 2024
On filings since 2021
40 hrs/week
$10K (2021) → $500K (2024)
Zachary Handelman
Treasurer, Vice President & Director of Operations
Treasurer & Director of Operations → Treasurer, Vice President & Director of Operations, 2023
On filings since 2022
30 hrs/week
$205K (2022) → $210K (2024)
Scott Handelman
Director
New on the 2024 filing
2 hrs/week
$10K (2024)
Former officers (4)
- Former: Donald Handlemen (2023) — Director
- Former: Donald E. Handelman (2020–2022) — Vice President
- Former: Joseph Handelman (2020–2021) — Director
- Former: William S. Miller (2020–2021) — Director
Data from IRS Form 990 filings, 2020–2024. "On filings since" is the earliest filing we hold that lists the person; hours are average hours per week as reported.
Compensation Overview
From 2024 IRS filing
The highest reported compensation on the 2024 filing was $500K, to Howard Chester (Secretary/Director). 7 officers or directors reported compensation on that filing.
Frequently asked questions about The G Harold & Leila Y Mathers
How much does The G Harold & Leila Y Mathers give each year?
The G Harold & Leila Y Mathers gave $17.3M across 103 grants in 2024, according to its 2024 IRS Form 990-PF. In 2023 it gave $16.5M across 76 grants.
What is The G Harold & Leila Y Mathers's typical grant size?
The G Harold & Leila Y Mathers's median grant in 2024 was $225,000, and its average grant was $167,707, across 103 grants on its 2024 IRS Form 990-PF. Organizations receiving their first grant from The G Harold & Leila Y Mathers that year got $172K on average.
Where does The G Harold & Leila Y Mathers give grants?
The G Harold & Leila Y Mathers's top state is Massachusetts, with 37% of the grant dollars itemized on its 2024 IRS Form 990-PF. The next largest states were New York (20%) and California (18%). The most frequent recipient cities were Boston, MA (30 grants), New York, NY (18 grants), Cleveland, OH (5 grants) and Pasadena, CA (5 grants).
Does The G Harold & Leila Y Mathers give general operating support?
Occasionally: 9% of The G Harold & Leila Y Mathers's 2024 grants with a stated purpose (9 of 103) were for general or operating support, per its 2024 IRS Form 990-PF. Recurring purposes include "Research Project" (94 grants).
Who are The G Harold & Leila Y Mathers's largest grantees?
The G Harold & Leila Y Mathers's largest 2024 grantees include Dana-Farber Cancer Institute ($1,918,333 across 10 grants), Children's Hospital Corp (Boston Children's Hospital) ($1,537,139 across 7 grants) and President and Fellows of Harvard College ($976,856 across 5 grants), according to its 2024 IRS Form 990-PF. Together they received 26% of its itemized 2024 grant dollars.
How large is The G Harold & Leila Y Mathers?
The G Harold & Leila Y Mathers reported $107.9M in total assets on its 2024 IRS Form 990-PF. It paid out $18.6M in qualifying distributions that year, against a required minimum of $19.4M (roughly 5% of its investment assets). Falling short in one year is not a violation: foundations have until the end of the next year to meet the minimum.
What does The G Harold & Leila Y Mathers fund?
The foundation’s mission is to advance knowledge in the life sciences by funding bold, basic scientific research with the potential to transform human health. See mission & focus areas ↑
How do I apply for a grant from The G Harold & Leila Y Mathers?
Applications go through the foundation’s online portal in a formal two-step process. Eligibility and process details are in the grantmaking section of this profile. See how to apply ↑
What is The G Harold & Leila Y Mathers's EIN?
The G Harold & Leila Y Mathers's EIN (Employer Identification Number) is 23-7441901. IRS Form 990 filing data is available on this page for 2020–2024.
Data last updated October 2026. Sourced from IRS Form 990-PF filings. Research dossier generated September 2026.
Data update history
(1)
When this profile's IRS filing data changed on Grantable
- IRS filings on file for fiscal years 2020–2024
Explore Open Grants
Browse active grant opportunities in The G Harold & Leila Y Mathers's focus areas in our free grants database
Similar Funders
Funders that support many of the same organizations
The Trustees of Columbia University in the City of New York
New York, NY
Columbia funds research, education and research, and capital projects, primarily through grants to universities and medical and research institutions across the United States, with the largest share going to New York recipients. Its 2025 grants had a median of about $109,000, though awards ranged from $5,350 to $15.1 million. The profile does not state whether it accepts unsolicited requests.
Assets
$26.0B
Grants
417
Total Given
$208.3M
The Chicago Community Trust
Chicago, IL
The Chicago Community Trust funds eligible nonprofits working to narrow the wealth gap and meet urgent needs, with priorities including economic mobility, education, jobs, homeownership, and community development in metropolitan Chicago and Cook County. Its 2025 grants had a median of $26,500, though amounts varied widely; the profile does not state whether it accepts unsolicited requests.
Assets
$7.1B
Grants
4,316
Total Given
$1.2B
The Pew Charitable Trusts
Washington, DC
The Pew Charitable Trusts funds nonpartisan policy research and initiatives, civic participation, and—especially in Philadelphia—arts and culture and services for people in need. Its 2025 grants had a median of $75,000, though amounts varied widely; funding is national, with substantial support in Washington, D.C., and Pennsylvania. The profile does not state whether Pew accepts unsolicited requests.
Assets
$1.5B
Grants
535
Total Given
$140.6M
Emory University
Atlanta, GA
Emory University primarily funds research and subcontract work for universities, hospitals, research organizations, and other organizations, across a range of academic and health-related fields. Its 2025 grants ranged from $5,500 to $19.1 million, with a median of about $97,000; 41% of grant dollars went to Georgia recipients. The profile does not state whether Emory accepts unsolicited requests.
Assets
$24.9B
Grants
362
Total Given
$183.7M
American Heart Association Inc
Dallas, TX
The American Heart Association funds basic, clinical, behavioral, translational and population research on cardiovascular, cerebrovascular and brain health, along with research training and education programs. In 2025 it awarded 833 grants totaling about $198 million; amounts ranged from $5,000 to nearly $9.93 million, with a median of $20,000. Research awards are for eligible U.S.-based nonprofit institutions, and the profile describes a formal proposal process but does not state whether unsolicited requests are accepted.
Assets
$2.0B
Grants
833
Total Given
$198.2M
Silicon Valley Community Foundation
Mountain View, CA
Silicon Valley Community Foundation funds work in areas such as housing, economic security, education, health, the environment, arts and culture, and civic engagement, with Community Action Grants supporting local, community-led organizations in San Mateo and Santa Clara counties. Its 2024 grants had a median of $51,716, though amounts varied widely; applications depend on the program, and SVCF states that it does not accept unsolicited proposals for advised funds.
Assets
$12.3B
Grants
3,576
Total Given
$3.2B
More similar funders
More Funders in New York
Cite this profile
Grantable. (2026). The G Harold & Leila Y Mathers funder profile. GrantGraph. Retrieved October 14, 2026, from https://grantable.co/funders/the-g-harold-and-leila-y-mathers-morg_f6c405f884f94b3ea6b413783d2190e1
BibTeX
@misc{grantable_237441901_2026,
author = {{Grantable}},
title = {{The G Harold \& Leila Y Mathers funder profile}},
howpublished = {GrantGraph},
year = {2026},
url = {https://grantable.co/funders/the-g-harold-and-leila-y-mathers-morg_f6c405f884f94b3ea6b413783d2190e1},
note = {Accessed 2026-10-14. Data licensed CC BY 4.0}
}The figures on this page are open data under CC BY 4.0: reuse them with credit to Grantable and a link. Download the data.
Figures come from The G Harold & Leila Y Mathers's IRS filings (methodology). AI-written summaries, news items and logos are not covered by the open licence. Spot an error? Email hello@grantable.co.
The G Harold & Leila Y Mathers down — hundreds of funders to go?