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· Private foundation

Halvorsen Family Foundation

Its FY2025 filing reports that it funds preselected organizations and did not take unsolicited requests; check the foundation's own site before ruling it out.

$35M
Granted FY2025still arriving
33
Grants FY2025still arriving
8
States reached
$20M
Largest
01What you fundRead
02The needRead
03Your edgeRead
04Your fieldRead
01What you fund
0198% classified

What you funded, over time

Every grant placed by its stated purpose and the recipient’s mission, by year — across FY2018–2025.

Education$58MHealth$18MPhilanthropy$14MArts & Culture$12MSocial Science$2.2MRecreation & Sports$1.8MAnimals$1.1MInternational$156kOther$0
02FY2025 · 33 grants

Where the money goes

Your grants by size, and where they go.

By grant size · FY2025

  • Under $10k6 grants · $21k
  • $10k–50k13 grants · $181k
  • $50k–250k6 grants · $550k
  • $250k+8 grants · $34M
$20,000
Median grant
8
States reached
$365M
Total assets
Largest grants
RecipientAmount
Individual grant recipient$20,000,000
STERLING AND FRANCINE CLARK ART INSTITUTE$5,125,000
MEMORIAL SLOAN KETTERING CANCER CENTER$5,000,000
GREEN MOUNTAIN VALLEY SCHOOL$1,500,000
WEILL CORNELL MEDICINE$1,000,000
US SKI & SNOWBOARD$500,000
WILDLIFE CONSERVATION SOCIETY$350,000
THE ROCKEFELLER UNIVERSITY$275,000
WILLIAMS COLLEGE$200,000
TEACHERS COLLEGE COLUMBIA UNIVERSITY$100,000
STANFORD UNIVERSITY$100,000
THE MUSEUM OF MODERN ART$50,000
THE HOSPITAL FOR SPECIAL SURGERY FUND INC$50,000
NEW ENGLAND NORDIC SKI ASSOCIATION$50,000
NORWEGIAN-AMERICA ASSOCIATION$26,464
02The need
03

Do your dollars go where the need is?

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

show:

Dollar for dollar, your grants (FY18–25) land where the poverty rate runs at 10%, against an area that typically sits at 10%. 35% of your dollars go to grantees based in above-average-need neighborhoods. Your grants skew toward lower-need ZIPs.

area typical 10%WILLIAMS COLLEGE: $7.5M → 12%NATIONAL NORDIC FOUNDATION: $100k → 14%JP MORGAN CHARITABLE FUND: $9.3M → 7%STANFORD MEDICAL DEVELOPMENT: $20.0M → 7%STANFORD UNIVERSITY - GSB: $1.0M → 8%MEMORIAL SLOAN KETTERING CANCER CENTER: $5.3M → 9%HOSPITAL FOR SPECIAL SURGERY: $3.0M → 17%WILDLIFE CONSERVATION SOCIETY: $350k → 28%US SKI & SNOWBOARD: $1.0M → 5%GREEN MOUNTAIN VALLEY SCHOOL: $1.5M → 9%NENSA: $50k → 7%STERLING AND FRANCINE CLARK ART INSTITUTE: $5.5M → 12%JP MORGAN CHARITABLE FUND: $5.1M → 7%STANFORD MEDICAL DEVELOPMENT: $20.0M → 7%STANFORD UNIVERSITY: $440k → 8%MEMORIAL SLOAN KETTERING CANCER CENTER: $5.0M → 9%THE HOSPITAL FOR SPECIAL SURGERY FUND INC: $2.0M → 17%WILDLIFE CONSERVATION SOCIETY: $350k → 28%US SKI & SNOWBOARD: $500k → 5%GREEN MOUNTAIN VALLEY SCHOOL INC: $55k → 9%NEW ENGLAND NORDIC SKI ASSOCIATION: $50k → 7%STERLING AND FRANCINE CLARK ART INSTITUTE: $5.1M → 12%STANFORD UNIVERSITY: $100k → 8%TEACHERS COLLEGE COLUMBIA UNIVERSITY: $100k → 17%WILDLIFE CONSERVATION SOCIETY: $100k → 28%WILLIAMS COLLEGE: $3.7M → 12%THE HOSPITAL FOR SPECIAL SURGERY FUND INC: $100k → 17%WILDLIFE CONSERVATION SOCIETY: $100k → 28%STERLING AND FRANCINE CLARK INSTITUTE: $2.1M → 12%TEACHERS COLLEGE COLUMBIA UNIVERSITY: $100k → 17%WILDLIFE CONSERVATION SOCIETY: $100k → 28%WILLIAMS COLLEGE: $750k → 12%THE HOSPITAL FOR SPECIAL SURGERY FUND INC: $60k → 17%WILLIAMS COLLEGE: $550k → 12%TEACHERS COLLEGE COLUMBIA UNIVERSITY: $100k → 17%STERLING AND FRANCINE CLARK ART INSTITUTE: $479k → 12%WILLIAMS COLLEGE: $350k → 12%WILLIAMS COLLEGE: $200k → 12%WEILL CORNELL MEDICINE: $1.3M → 17%WILLIAMS COLLEGE: $200k → 12%WEILL CORNELL MEDICINE: $1.0M → 17%STERLING AND FRANCINE CLARK ART INSTITUTE: $100k → 12%THE ROCKEFELLER UNIVERSITY: $600k → 17%STERLING AND FRANCINE CLARK INSTITUTE: $100k → 12%THE ROCKEFELLER UNIVERSITY: $275k → 17%ROCKEFELLER UNIVERSITY: $200k → 17%MOMA: $100k → 17%THE ROCKEFELLER UNIVERSITY: $150k → 17%0%20%40%50%more need →
grant to an above-average-need area below average· circle size = grant amount

Matched: human-services grants are those whose grantee’s IRS cause code is Human Services. Placed by people below the poverty linein the grantee’s ZIP, averaged from the tracts in that ZIP; grantee ZIP can differ from where services are delivered.

Which US states your grants reach

ME
VT
MN
NY
MA
PA
CT
CA
UT

US grants placed by each grantee’s ZIP, which can differ from where services are actually delivered. Need from public data — U.S. Census/ACS, CDC PLACES, Eviction Lab, USDA — shown as context about the area, never attributed to your giving.

03Your edge
repeat funding

Who you back again

Which organizations you funded more than once, and which you funded a single time. Each grantee is matched to its own filings.

96%of every dollar goes to organizations you’ve funded before.
$102M · 33 repeat orgs$4.6M to everyone else

33 repeat relationships — 27 still active in FY2025, 6 since wound down; 5 grantees were first funded in FY2025 (too recent to call).

How the two cohorts compare

Re-uppedFunded once

Organizations

33
10

Total granted

$102M
$4.5M

Median revenue growth · since first grant

+18%
+213%

Still filing today

73%
10%

New vs renewed · share of each year

In FY2025, 100% of grant dollars renewed an existing relationship; $112k went to new ones.

50%100%’19’20’21’22’23’24’25
RenewedFirst-time

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

’19’20’21’22’23’24’25
EducationArts & CultureEnvironmentRecreation & SportsHealthAnimalsOther

First-time = a grantee’s first year in your filing window; renewed = funded in an earlier year too. As a portfolio matures the renewed share naturally climbs — once funded, an org stays “renewable” — so the signal is the years that buck it (a new-grantee intake wave). 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

  • SA
    STERLING AND FRANCINE CLARK ART INSTITUTE
    6× · 2020–2025 · $13M · revenue +123% · 51% of their budget
  • Williams College
    7× · 2019–2025 · $13M · revenue +13%
  • TH
    The Hospital for Special Surgery Fund Inc
    4× · 2022–2025 · $2.2M · revenue +16%

Funded once

  • HF
    HOSPITAL FOR SPECIAL SURGERY
    one grant, 2021 · $3.0M
  • SU
    STANFORD UNIVERSITY - GSB
    one grant, 2020 · $1.0M
  • IG
    Individual grant recipient
    one grant, 2020 · $140k

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

04Your field

The map has a center of gravity: the average direction from the rest of the sector toward the organizations the foundation funds — the shape of its giving. Scoring every nonprofit along that direction surfaces the ones that look most like the portfolio. These are the closest matchesthat aren’t grantees — a resemblance in what they say they do, not a recommendation.

1
Trustees of Dartmouth College

Dartmouth College educates the most promising students and prepares them for a lifetime of learning and of responsible leadership, through a faculty dedicated to teaching and the creation of knowledge.

Education
2
President and Trustees of Bates College

Bates is a college of the liberal arts and sciences, and is a coeducational, nonsectarian, residential college with special commitments to academic rigor, and to assuring in all of its efforts the dignity of each individual, and access to…

Education
3
Harvard Conservation Trust

To preserve the unique character and natural resources of harvard.

Environment
4
American Astronomical Society

The american astronomical society (aas), established in 1899, is the major organization of professional astronomers in north america. the basic objective of the aas is to promote the advancement of astronomy and closely related branches of…

Science & Tech
5
University of New Haven

The University of New Haven is a student-centered comprehensive university with an emphasis on excellence in liberal arts and professional education. Our mission is to prepare our students to lead purposeful and fulfilling lives in a…

Education
6
Boston Architectural College

The bac is committed to provide excellence in design education grounded in practice and accessible to diverse communities.

—
7
United States Naval Institute

Provide an independent forum for those who dare to read, think, speak, and write to advance the professional, literary, and scientific understanding of sea power and other issues critical to global security.

—
8
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
9
Marine Biological Laboratory

The Marine Biological Laboratory (MBL) is a world-renowned center for biological discovery and training that is notably affiliated with more than 60 Nobel Prize winners. Research is conducted by full-time faculty as well as hundreds of the…

Science & Tech
10
Saint Anselm College

Saint anselm is a catholic, benedictine college providing all of its students a distinctive liberal arts education that incorporates opportunities for professional and career preparation. it does so in a learning community that encourages…

Education
11
Wheaton College

Wheaton college provides a transformative liberal arts education, combining theory and practice, for intellectually curious students within a collaborative and vibrant extended community and network that values and strives to create an…

Education
12
The Trustees of Reservations

Overview - founded in boston by pioneering landscape architect and open space visionary charles eliot in 1891, the trustees is the nation's first and the commonwealth's largest conservation and preservation nonprofit.

Environment

For reference, the grantee most central to the portfolio’s shape is Stowe Land Trust and the most unlike its peers is Stowe Swimmers Foundation Ltd D/B/a the Swimming Hole. Resemblance is measured on each organization’s own IRS 990 mission text; it reflects how work is described, not its quality or impact.

For each theme you fund, this compares how the sector’s money is shifting with how your own giving is shifting.

← shrinkinggrowing →↓ leaning in → pulling backsteadyCommunity Arts OrganizationsCommunity Health CentersYouth Ice Hockey ProgramsLand Conservation Organizat…Volunteer Fire DepartmentsCommunity FoundationsPublic Library SupportEducation Equity LeadershipDevelopmental Disabilities …Faith-Based Liberal Arts Co…
the sector your giving your giving is ahead of the sector the sector’s ahead of you· dot size = how much the theme matters to each side
Ordered by the change in your giving — leaning in on top, pulling back at the bottom. The bar between the two dots is how out of step you are with the sector. Hover any row for detail.

Sector change and giving change are each shown relative to their own range, growing (right) or shrinking (left); both normalized, so inflation isn’t mistaken for growth.

Your grantees are a median of 41 years old; the field is 16. You back the established end — and your money leans older still.

THE FIELDby orgYOUR GRANTEESby number22%0%<5yr14%7%5–10yr19%0%10–20yr16%29%20–35yr13%32%35–55yr16%32%55yr+
THE FIELDby orgYOUR MONEYby value22%0%<5yr14%0%5–10yr19%0%10–20yr16%3%20–35yr13%12%35–55yr16%85%55yr+

The field is 22% startups (under 5 years old) — 0% of your grantees by number, and just 0% of your money.

Closures · last 5 years

The orgs you fund almost never close — 0.0% lost their exemption, against 13% of the field you don’t fund.

orgs you fund
0.0%0/29
the rest of the field
13%
240,396/1,819,536

Age = years since IRS exemption (a founding proxy). “Closed” = auto-revocation for 3 years of non-filing — a floor on closure, not proof, and bigger established orgs lapse least. Association, not causation.

04the grantee network

29 grantees tracked through their own filings, 2017–2025.

Each one resolved to its own IRS returns and tracked year by year — your grant beside their revenue from every source. Association, dated; never a causal claim.

Counted here: distinct organizations you funded across 2017–2025, not grant rows in a single year — so this will not match the grant count on the cover. 29 of the 49 grantees resolved in that span have returns of their own we could reconcile; the rest are funded organizations whose filings we could not track year by year.

2
Load-bearing (≥25% of a budget)
5
Early backer (in before they grew)
29/29
Grantees still filing
21/29
Grew since you first funded

Where your money sits — by cause, then by grantee

Individual grant recipient — $40,000,000 · OtherIndividual grant recipientJP MORGAN CHARITABLE FUND — $14,382,500 · OtherJP MORGAN CHARITABLE FUNDMEMORIAL SLOAN KETTERING CANCER CENTER — $10,250,000 · OtherMEMORIAL SLOAN KETTERING CANCER CENTERHOSPITAL FOR SPECIAL SURGERY — $3,000,000 · Other+23 more — $5,699,933 · Other+23 moreWilliams College — $13,213,743 · EducationWilliams CollegeGREEN MOUNTAIN VALLEY SCHOOL INC — $1,605,000 · EducationGREEN MOUNTAIN VA…THE ROCKEFELLER UNIVERSITY — $1,275,000 · EducationTHE ROCKEFELLER U…+5 more — $930,200 · Education+5 moreSTERLING AND FRANCINE CLARK ART INSTITUTE — $13,374,000 · Arts & CultureSTERLING AND F…+4 more — $290,000 · Arts & CultureThe Hospital for Special Surgery Fund Inc — $2,210,000 · Health+1 more — $45,000 · HealthWildlife Conservation Society — $1,000,000 · AnimalsNATIONAL NORDIC FOUNDATION — $145,000 · Recreation & SportsNEW ENGLAND NORDIC SKI ASSOCIATION INC — $50,000 · Recreation & SportsCONNECTICUT AUDUBON SOCIETY INC — $75,000 · EnvironmentWESTPORT RIVER WATERSHED ALLIANCE INC — $30,000 · EnvironmentSTOWE LAND TRUST — $20,000 · EnvironmentDARIEN NATURE CENTER INC — $15,000 · Environment
Other$73,332,433Education$17,023,943Arts & Culture$13,664,000Health$2,255,000Animals$1,000,000Recreation & Sports$195,000Environment$140,000

Each org by its size and your share of it — top-left is where you’re load-bearing

25%50%75%100%$1.0M$10M$100Mgrantee revenue →↑ your share of their budgetSTERLING AND FRANCINE CLARK ART INSTITUTE — $13,374,000 over 6y, 51% of budgetWilliams College — $13,213,743 over 7y, 1.6% of budgetThe Hospital for Special Surgery Fund Inc — $2,210,000 over 4y, 6.8% of budgetGREEN MOUNTAIN VALLEY SCHOOL INC — $1,605,000 over 3y, 13% of budgetTHE ROCKEFELLER UNIVERSITY — $1,275,000 over 5y, 0.1% of budgetWildlife Conservation Society — $1,000,000 over 5y, 0.1% of budgetTHE BOARD OF TRUSTEES OF THE LELAND STANFORD JUNIOR UNIVERSITY — $540,200 over 2y, 0.0% of budgetTeachers College Columbia University — $300,000 over 3y, 0.0% of budgetNATIONAL NORDIC FOUNDATION — $145,000 over 4y, 15% of budgetMuseum of Modern Art — $100,000 over 2y, 0.0% of budgetGREENS LEDGE LIGHT PRESERVATION SOCIETY INC — $85,000 over 3y, 5.9% of budgetCONNECTICUT AUDUBON SOCIETY INC — $75,000 over 2y, 0.7% of budgetTHE MARITIME AQUARIUM AT NORWALK INC — $60,000 over 3y, 0.2% of budgetDARIEN POLICE ASSOCIATION INC — $55,000 over 3y, 4.8% of budgetFRIENDS OF FONDATION DE FRANCE INC — $50,000 over 1y, 1.6% of budgetNEW ENGLAND NORDIC SKI ASSOCIATION INC — $50,000 over 1y, 7.2% of budgetMASSACHUSETTS MUSEUM OF CONTEMPORARY ART FOUNDATION INC — $50,000 over 3y, 0.1% of budgetSTOWE VOLUNTEER FIREFIGHTERS INC — $45,000 over 3y, 70% of budgetDARIEN EMS POST 53 INC — $45,000 over 3y, 3.0% of budgetDarien Community Association Inc — $45,000 over 3y, 2.0% of budgetDARIEN LIBRARY INC — $30,000 over 3y, 0.2% of budgetSTOWE RESCUE SQUAD INC — $30,000 over 3y, 13% of budgetWESTPORT RIVER WATERSHED ALLIANCE INC — $30,000 over 3y, 1.5% of budgetSTOWE LAND TRUST — $20,000 over 2y, 0.4% of budgetDARIEN NATURE CENTER INC — $15,000 over 3y, 0.5% of budgetTeach for America Inc — $10,000 over 1y, 0.0% of budgetCATAMOUNT TRAIL ASSOCIATION — $6,000 over 3y, 0.5% of budgetSTOWE SWIMMERS FOUNDATION LTD D/B/A THE SWIMMING HOLE — $6,000 over 3y, 0.2% of budget
Go grantee by grantee — a decade per org, and how each moved after you funded them

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

The grantmakers whose grantees overlap with yours far more than size alone predicts. Each orbits closer the stronger the alignment; the arcs between them show where they also fund each other. Here it reads as a tightly interlocked camp — most of these funders back each other's grantees too.

The Rogers Family Fou…The Meredith and Whit…Ibm International Fou…The Goodnow FundThe Darien Foundation…522 Foundation IncThe Roxe FoundationThe Wiggins Foundatio…The Weil FoundationViking Global Foundat…Fairfield County's Co…The Goldman Sachs Cha…
The Rogers Family FoundationCT15.7× affinity5 shared granteesties to 11 of 11Hover any node to trace its alignments.Compare side by side →

Open a dossier: The Rogers Family Foundation · The Meredith and Whitney George Family Foundation Inc · Ibm International Foundation · The Goodnow Fund · The Darien Foundation Inc · 522 Foundation Inc · The Roxe Foundation · The Wiggins Foundation Inc · The Weil Foundation · Viking Global Foundation Inc · Fairfield County's Community Foundation Inc · The Goldman Sachs Charitable Gift Fund

Affinity is a Gamma-Poisson posterior co-funding rate, re-centered on the typical rate, so thin evidence shrinks toward no signal. A research starting point: overlap is association, not proof of shared intent.

Government reliance of your grantees

Every dot is one organization Halvorsen Family Foundation funds. Left–right is the share of its income from government; up–down is the share from you. Bigger dots raise more. Filter to federal, a single department, or state — and drag the year to watch it move.

2024
’20’21’22’23’24’25
no gov · 90%5%19%42%75%your share of their income ↑0%13%25%38%50%share of the org’s income from government →median 5%
  • Stowe Land Trust — 10% of income from government
  • Catamount Trail Association — 10% of income from government
  • The Maritime Aquarium at Norwalk Inc — 5% of income from government
  • Connecticut Audubon Society Inc — 1% of income from government
  • Darien Nature Center Inc — 0% of income from government
  • Williams College — 0% of income from government
no gov moneyreceives it· size = income
9get no government money at all
4report government grants on their 990 we could not trace to a source (not plotted)
0rely on government for over half their income
⤢ axis zoomed · 0–50%
typical government reliance, FY20–25

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 your grant caused the public funding. Coverage is precision-first — a floor, not 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 12–24 months.

On method. Every financial figure here is read directly from IRS e-file XML — your own 990/990-PF and the multi-year returns of the 49 grantees we resolved across every year we hold, several hundred filings in all (a different count from the grant rows on the cover, which are one fiscal year)— each linked to its source. Grantee achievements and outcomes are each organization’s own program-service reporting (Form 990, Part III); we read these as association with sustained funding — the foundation is one of several forces — suppress low-confidence name matches rather than guess, and say so where a figure rests on a single grant or filing. Not everything on this page is a filed figure, and the difference matters. Filed is what you reported on your 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. How we build these →

Generated from your IRS Form 990-PF e-file return for fiscal year 2025, released 2025. Filings run roughly 12–24 months behind; figures are dated accordingly.

Source object · view filing

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 camps
funders cluster by geography, not ideology
By state
where grant money is based, and what stays home
State money flows
the interactive map of money crossing state lines