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Stephen Mack & Kelly Mack Foundation Inc at a glance

· Private foundation

Stephen Mack & Kelly Mack Foundation Inc

Its FY2024 filing reports that it funds preselected organizations and did not take unsolicited requests; check the foundation's own site before ruling it out.

$1.1M
Granted FY2024still arriving
10
Grants FY2024still arriving
4
States reached
$305k
Largest
01What it fundsRead
02The needRead
03Its granteesRead
04Its fieldRead
05Through PlinthRead
01What it funds
0189% classified

What it funded, over time

Every grant placed by its stated purpose and the recipient’s mission, by year, FY2021 to 2024.

Health$1.1MPhilanthropy$695kEducation$669kHuman Services$413kInternational$130kAnimals$28kRecreation & Sports$10kFood & Nutrition$5kOther$0
02FY2024 · 10 grants

Where the money goes

Grants by size, and the largest recipients.

By grant size · FY2024

  • Under $10k3 grants · $11k
  • $10k–50k1 grant · $10k
  • $50k–250k3 grants · $260k
  • $250k+3 grants · $805k
$87,500
Median grant
4
States reached
$30k
Total assets
Largest grants
RecipientAmount
NYU$305,000
NYU LANGONE HEALTH$250,000
MUSICIANS ON CALL$250,000
92Y$122,667
GEORGETOWN UNIVERSITY$87,500
RIVERDALE COUNTRY SCHOOL$50,000
THE SCHWARZMAN ANIMAL MEDICAL CENTER$10,000
BOSTON CHILDREN'S HOSPITAL TRUST$7,500
LUSTGARTEN FOUNDATION$1,500
ATLANTIC GOLF CLUB EDUCATIONAL FUND$1,500
02The need
03

Does the money reach high-need areas?

Each grant placed by the hardship in its grantee’s ZIP, against the area’s typical level.

show:

Its human-services grants (FY21–24, $113k) land where the poverty rate runs at 16%, against an area that typically sits at 10%. 99% of those dollars go to grantees based in above-average-need neighborhoods. Most of its grants land in higher-need ZIPs.

area typical 10%CHALLENGED ATHLETES FOUNDATION: $10k → 11%VISTA DEL MAR CHILD AND FAMILY SERVICES: $1k → 14%LUSTGARTEN FOUNDATION: $2k → 6%AMERICAN FRIENDS OF OR NATIONAL MISSION: $100k → 17%0%20%40%50%more need →
grant to an above-average-need area below average· circle size = grant amount
How this is measured
Matched: human-services grants are those whose grantee’s IRS cause code is Human Services. Placed by people below the poverty line in the grantee’s ZIP, averaged from the tracts in that ZIP.
How this is measured
US grants placed by each grantee’s ZIP, which can differ from where services are delivered. Need from public data (U.S. Census/ACS, CDC PLACES, Eviction Lab, USDA), shown as context about the area, never attributed to the funder’s giving.
03Its grantees
repeat funding

Who it funds again

Organizations funded in more than one year, against those funded once.

84%of every dollar goes to organizations it has funded before.
$2.9M · 10 repeat orgs$554k to everyone else

Grantees it renews have grown median revenue +19% since the first grant, against 0% for those funded once.

10 repeat relationships: 8 still active in FY2024, 2 since wound down; 2 grantees were first funded in FY2024 (too recent to call).

How the two cohorts compare

Re-uppedFunded once

Organizations

10
8

Total granted

$2.9M
$551k

Median revenue growth · since first grant

+19%
0%

Still filing today

70%
63%

New vs renewed · share of each year

In FY2024, 100% of grant dollars renewed an existing relationship; $3k went to new ones.

50%100%’21’22’23’24
RenewedFirst-time

Where new relationships form · theme of each grantee’s first grant

’21’22’23’24
PhilanthropyHuman ServicesAnimalsEducationArts & CultureFood & NutritionOther
How this is measured
First-time means a grantee’s first year in the filing window; renewed means funded in an earlier year too. The renewed share climbs naturally as a portfolio matures, so the signal is a year that bucks it (a wave of new grantees). The earliest year is left-censored: relationships that predate the data read as new. Theme is the grantee’s IRS cause.

Backed again, and grew

  • MO
    MUSICIANS ON CALL INC
    3× · 2021–2024 · $500k · revenue +30%
  • GEORGETOWN UNIVERSITY
    2× · 2023–2024 · $238k · revenue +19%
  • RC
    RIVERDALE COUNTRY SCHOOL INC
    2× · 2023–2024 · $75k · revenue +9%

Funded once

  • SD
    STEPHEN D HASSENFELD CHILDREN'S CENTER
    one grant, 2021 · $412k
  • AF
    American Friends Of Or National Missions
    one grant, 2023 · $100k · revenue 0%
  • TT
    THE TOM COUGHLIN JAY FUND FOUNDATION INCgraduated
    one grant, 2021 · $13k · revenue +130%
How this is measured

Repeat means funded in two or more distinct years. Growth and survival are read from each grantee’s own subsequent IRS filings.

04Its field

Closest unfunded matches

The nonprofits that most resemble its grantees but are not funded by it, scored along the direction from the rest of the field toward the portfolio. A resemblance in what they say they do, not a recommendation.

1
The Children's Hospital of Philadelphia

The children's hospital of philadelphia, the oldest hospital in the united states dedicated exclusively to pediatrics, strives to be the world leader in the advancement of health care for children by integrating excellent patient care,…

Health
2
Massachusetts Institute of Technology

The mission of mit is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the 21st century.

Education
3
New York University

Nyu is a private university with approximately 60,000 matriculating students in 20 schools and institutes. nyu's primary missions are education, research and scholarship, and patient care.

Education
4
Children's Health Care

We champion the health needs of children and families. we are committed to improving children's health by providing the highest-quality, family centered care, advanced through research and education.

Health
5
Association of American Medical Colleges

Aamc leads & serves the academic medicine community to improve the health of people everywhere.

Education
6
American Society of Clinical Oncology Inc

See schedule o:asco is a professional oncology society committed to conquering cancer through research, education, and promotion of the highest quality patient care.

Health
7
Memorial Sloan-Kettering Cancer Center

Leadership in the prevention, treatment, and cure of cancer through excellence, vision and cost effectiveness in patient care, outreach programs, research, and education.

Health
8
New York Genome Center Inc

Operate a state-of-the-art, world-class genomic research center that creates and uses advanced genomics to understand the genetic basis of disease. for more information, see schedule o.

Health
9
Asco Association

Asco association promotes the common business interests of its members by: (1) advocating for policies that improve the quality of cancer care; (2) maintaining the highest standards of oncology medical care through programs supporting…

Community Improvement
10
The American College of Trust and Estate Counsel

Enhance the ability of actec members to provide the most efficient and highest quality services to their clients; develop qualified trust and estate counselors; improve and reform probate, trust and tax laws, procedures, and standards of…

Community Improvement
11
Sanford Burnham Prebys Medical Discovery Institute

Sanford burnham prebys medical discovery institute's mission is to advance the biomedical sciences by cultivating the next generation of scientific leaders, providing meaningful opportunities for researchers of all backgrounds to learn,…

Health
12
University of Southern California

The central mission of the university of southern california is the development of human beings and society as a whole through the cultivation and enrichment of the human mind and spirit. the principal means by which our mission is…

Education
How this is measured
The grantee most central to the portfolio’s shape is Team Impact Inc; the most unlike its peers is Home Stretch Farm and Sanctuary. Resemblance is measured on each organization’s own IRS 990 mission text; it reflects how work is described, not its quality or impact.
04the grantee network

16 grantees tracked through their own filings, 2017–2026.

Each grant beside the grantee’s revenue from every source, year by year.

How this is measured

Counted here: distinct organizations funded across 2017 to 2026, not grant rows in a single year, so this will not match the grant count on the cover. 16 of the 21 grantees resolved in that span have returns of their own we could reconcile.

Each grantee is resolved to its own IRS returns. Association, dated; never a causal claim.

0
Load-bearing (≥25% of a budget)
1
Early backer (in before they grew)
15/16
Grantees still filing
9/16
Grew since first funded

Where the money sits, by cause and then by grantee

NYU LANGONE HEALTH: $515,000 · OtherNYU LANGONE HEALTH92Y: $429,288 · Other92YSTEPHEN D HASSENFELD CHILDREN'S CENTER: $412,000 · OtherSTEPHEN D HASSENFELD CHILDREN'S CENTERNYU: $355,000 · OtherNYU+1 more: $2,500 · OtherMONTEREY PENINSULA FOUNDATION: $695,000 · PhilanthropyMONTEREY PENINSULA FOUNDA…TEAM IMPACT INC: $60,000 · PhilanthropyTEAM IMPACT INCCHARITIES AID FOUNDATION AMERICA: $30,000 · Philanthropy+2 more: $14,000 · PhilanthropyMUSICIANS ON CALL INC: $500,000 · Arts & CultureMUSICIANS ON CAL…GEORGETOWN UNIVERSITY: $237,500 · EducationGEORGETOWN…RIVERDALE COUNTRY SCHOOL INC: $75,000 · EducationRIVERDALE …American Friends Of Or National Missions: $100,000 · Human ServicesCHALLENGED ATHLETES INC: $10,000 · Human Services+2 more: $2,500 · Human ServicesTHE ANIMAL MEDICAL CENTER: $20,000 · AnimalsHOME STRETCH FARM AND SANCTUARY: $8,000 · AnimalsChildren's Hospital Corporation: $15,000 · HealthCITYMEALS-ON-WHEELS: $5,000 · Food & Nutrition
Other$1,713,788Philanthropy$799,000Arts & Culture$500,000Education$312,500Human Services$112,500Animals$28,000Health$15,000Food & Nutrition$5,000

Each grantee by its size and the funder’s share of it; top left is load-bearing

25%50%75%100%$10M$100Mgrantee revenue →↑ funder's share of their budgetMONTEREY PENINSULA FOUNDATION: $695,000 over 3y, 0.9% of budgetMUSICIANS ON CALL INC: $500,000 over 3y, 5.5% of budgetGEORGETOWN UNIVERSITY: $237,500 over 2y, 0.0% of budgetAmerican Friends Of Or National Missions: $100,000 over 1y, 1.6% of budgetRIVERDALE COUNTRY SCHOOL INC: $75,000 over 2y, 0.1% of budgetTEAM IMPACT INC: $60,000 over 2y, 0.5% of budgetCHARITIES AID FOUNDATION AMERICA: $30,000 over 1y, 0.0% of budgetTHE ANIMAL MEDICAL CENTER: $20,000 over 2y, 0.0% of budgetChildren's Hospital Corporation: $15,000 over 2y, 0.0% of budgetTHE TOM COUGHLIN JAY FUND FOUNDATION INC: $12,500 over 1y, 0.3% of budgetCHALLENGED ATHLETES INC: $10,000 over 1y, 0.1% of budgetCITYMEALS-ON-WHEELS: $5,000 over 1y, 0.0% of budgetMARC LUSTGARTEN PANCREATIC CANCER FOUNDATION: $1,500 over 1y, 0.0% of budgetATLANTIC GOLF CLUB EDUCATIONAL FUND INC: $1,500 over 1y, 0.4% of budgetVISTA DEL MAR CHILD AND FAMILY SERVICES: $1,000 over 1y, 0.0% of budget
Grantee by grantee: a decade per organization, before and after funding

A decade per grantee: revenue shaded, grants as bars, all rows on one timeline.

Co-funders

Grantmakers whose grantees overlap with this funder’s far more than size alone predicts. Closer means stronger alignment; arcs show where they also fund each other. Here they form a tightly interlocked group: most of these funders back each other's grantees too.

American Online Givin…Donor Advised Charita…Fidelity Investments …Amazonsmile Foundation
American Online Giving Foundation IncDE7.2× affinity4 shared granteesties to 3 of 3Hover any node to trace its alignments.Compare side by side →

Open a dossier: American Online Giving Foundation Inc · Donor Advised Charitable Giving Inc · Fidelity Investments Charitable Gift Fund · Amazonsmile Foundation

How this is measured
Affinity is a Gamma-Poisson posterior co-funding rate, re-centered on the typical rate, so thin evidence shrinks toward no signal. Overlap is association, not proof of shared intent.

How much its grantees rely on government

Each dot is one organization Stephen Mack & Kelly Mack Foundation Inc funds: left to right is the share of its income from government, bottom to top the share from Stephen Mack & Kelly Mack Foundation Inc. Bigger dots raise more.

2024
’20’21’22’23’24’25
no gov · 20%1%3%6%10%funder's share of their income ↑0%10%20%30%40%share of the org’s income from government →median 10%
  • Children's Hospital Corporation: 10% of income from government
no gov moneyreceives it· size = income
2get no government money at all
1report government grants on their 990 we could not trace to a source (not plotted)
0rely on government for over half their income
⤢ axis zoomed · 0–40%
typical government reliance, FY20–25
How this is measured
Government income is each org’s traced federal awards (USASpending grants and contracts) plus state payments (open checkbooks) as a share of its total revenue (IRS Form 990); the self-reported government-grant line (990 line 1e) is carried for cross-check: a grantee that reports government grants we could not trace to a source is left off the chart rather than shown as receiving none. An association, not a claim that a grant caused the public funding. Coverage is precision-first, a floor rather than a census; state records exist for 9 states, so a grantee outside them shows no state figure (dimmed) rather than a false zero. Federal award amounts are obligations, which can span years, so a single-year share is indicative. 990 filings lag 12 to 24 months.
05Through Plinth

Warm introductions · Powered by PlinthPlus

How do I get to Stephen Mack & Kelly Mack Foundation Inc?

Find your warmest path to Stephen Mack & Kelly Mack Foundation Inc through trustees and officers whose names appear on both boards. Search for your organization and Plinth traces the shortest route it can evidence.

Each link is a name appearing on two organizations’ public IRS 990 filings, matched on that name and, where the filings support it, on location. A same-state match has geographic support, which is a second matching feature rather than confirmation that the two are one person; a cross-state one is the likeliest to be two people who share a name. Every hop shows its tier, low-confidence and distant paths are held back rather than guessed, and it is worth confirming the person before you use the introduction.

On method. Every financial figure here is read from IRS e-file XML, the funder’s own 990/990-PF, and from the multi-year returns of the 21 grantees we resolved, each linked to its source. Grantee outcomes are each organization’s own program-service reporting (Form 990, Part III), read as association with funding, never as caused by it. Low-confidence name matches are suppressed rather than guessed. How we build these →

How this is measured
Each figure carries one of six labels. Filed is what the funder reported on its return. Official is another government record about an organization, such as a federal award or a charity register, joined by name where no shared identifier exists. Resolved is an identity we worked out where the filing named a recipient without an EIN, kept only above a measured confidence threshold. Computed is arithmetic over those, like themes, portfolio clusters and co-funder strength. Context is a statistic about a place rather than about an organization, which is what the need overlay is: it describes the area a grantee’s address sits in, not where its work lands. Inferred is drawn by a model from text, like the partnerships read out of public news and organization websites. Each is labeled where it appears.

Generated from the IRS Form 990-PF e-file return for fiscal year 2024, released 2024. Filings run roughly 12 to 24 months behind; figures are dated accordingly.

Source object · view filing

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More from the funding graph

The unnamed billions
grants reported with no recipient in the public record
The regranting layer
51% of grant dollars land in the regranting layer
The DAF merry-go-round
$9.7B circulates between donor-advised funds
The endowment market
who holds foundation money, and what just moved
The camps
funders cluster by geography, not ideology
By state
where grant money is based, and what stays home