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Arntz Family Foundation at a glance

· Private foundation

Arntz 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.

$531k
Granted FY2023
27
Grants FY2023
5
States reached
$50k
Largest
01What it fundsRead
02Its granteesRead
03Its fieldRead
04Through PlinthRead
01What it funds
0191% classified

What it funded, over time

Every grant placed by its stated purpose and the recipient’s mission, by year, FY2017 to 2024.

Philanthropy$1.8MEnvironment$721kAnimals$41kHealth$10kYouth Development$10kArts & Culture$10kFood & Nutrition$6kEducation$5kOther$0
02FY2023 · 27 grants

Where the money goes

Grants by size, and the largest recipients.

How this is measured
The 27 grants below total $404,396, the rows itemized in this filing. The $531,397 headline is the total grant expense on the return; the other $127,001 is giving the schedule does not break out (grants under the $5,000 itemization floor, grants to individuals, grants on other schedules). Every figure below describes the itemized rows only.

By grant size · FY2023

  • Under $10k18 grants · $47k
  • $10k–50k5 grants · $157k
  • $50k–250k4 grants · $200k
$5,000
Median grant
5
States reached
$9.7M
Total assets
Largest grants
RecipientAmount
Earthjustice Legal Defense Fund$50,000
The Climate Center$50,000
Point Blue Conservation Science Conservation Service$50,000
Action for the Climate Emergency, Inc$50,000
Environment California Research & Policy Center$40,000
Seacology$35,000
Marine Conservation Institute$31,000
Sierra Nevada Alliance$30,000
Sonoma Ecology Center$21,000
Boys & Girls Club$9,250
Lifehouse Inc$7,888
KQED$7,500
Maui Food Bank$5,181
Marin County Office of Education$5,000
COTS$2,000
02Its grantees
repeat funding

Who it funds again

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

78%of every dollar goes to organizations it has funded before.
$642k · 11 repeat orgs$179k to everyone else

11 repeat relationships: 11 still active in FY2023, 0 since wound down; 16 grantees were first funded in FY2023 (too recent to call).

How the two cohorts compare

Re-uppedFunded once

Organizations

11
10

Total granted

$642k
$91k

Median revenue growth · since first grant

+53%
+72%

Still filing today

91%
50%

New vs renewed · share of each year

In FY2023, 78% of grant dollars renewed an existing relationship; $88k went to new ones.

50%100%’22’23
RenewedFirst-time

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

’22’23
EnvironmentFood & NutritionEducationHuman ServicesArts & CultureReligionOther
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

  • GE
    GOODPOWER EDUCATION FUND INC
    2× · 2022–2023 · $105k · revenue +77%
  • TC
    The Climate Center
    2× · 2022–2023 · $100k · revenue +53%
  • EARTHJUSTICE
    2× · 2022–2023 · $100k · revenue +26%

Funded once

  • PR
    Point Reyes Bird Observatory Conservation Service
    one grant, 2022 · $40k
  • GA
    GREENBELT ALLIANCEPEOPLE FOR OPEN SPACEgraduated
    one grant, 2022 · $40k · revenue +42%
  • SG
    Shifting Gears/M S Concours D'Elegance
    one grant, 2022 · $5k
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.

03Its 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
Sonoma Mountain Institute
Environment
2
Sustainable Conservation

Sustainable Conservation advances the collaborative stewardship of Californias land, air, and water for the benefit of nature and people. For over three decades, Sustainable Conservation has built coalitions of people with different…

Environment
3
Sonoma Botanical Garden
—
4
Sonoma County Conservation Action

Sonoma County Conservation Action's mission is to better our quality of life in Sonoma County for all generations, through educating and directly engaging the public on local environmental issues and policies using grassroots organizing.

—
5
Ecology Action of Santa Cruz

The primary and specific purpose for which the said corporation is formed is to empower individuals, businesses and communities to take actions today that achieve environmental and economic sustainability. The activities of the corporation…

Environment
6
Bay Nature Institute dba Bay Nature Bay Nature Magazine

Bay Nature connects the people of the San Francisco Bay Area to our natural world and motivates people to solve problems with nature in mind. Our vision is that all people have a close relationship with theirnatural world.

Environment
7
California Institute for Biodiversity

Create and publish educational materials, conduct professional development, promote awareness, and sponsor research on the spectacular biological diversity of the State of CA.

Education
8
Ecology Center

Inspiring and building a sustainable, healthy, and just future for the east bay, california, and beyond.

Environment
9
San Francisco Bay Bird Observatory

The San Francisco Bay Bird Observatory is dedicated to promote sustainability in the Bay Area and beyond by engaging communities in avian science, habitat restoration, and education.

Environment
10
The Union of Concerned Scientists Inc

The union of concerned scientists puts rigorous, independent science into action, developing solutions and advocating for a healthy, safe, and just future.

International
11
Rescape California

ReScape addresses climate change by providing a regenerative, nature-based whole systems foundation for landscaping education, workforce development and policy.Foundational to our work is a whole systems watershed framework that…

Environment
12
California Council for Environmental and Economic Balance

To create a california where balancing economic growth and environmental protection is not only a vision, but also a reality.

—
How this is measured
The grantee most central to the portfolio’s shape is Environment California Research and Policy Center; the most unlike its peers is Grand Circle Foundation Inc. Resemblance is measured on each organization’s own IRS 990 mission text; it reflects how work is described, not its quality or impact.
03the grantee network

24 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. 24 of the 37 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)
7
Early backer (in before they grew)
24/24
Grantees still filing
21/24
Grew since first funded

Where the money sits, by cause and then by grantee

GOODPOWER EDUCATION FUND INC: $105,000 · EnvironmentGOODPOWER EDUCATION FUND INCEARTHJUSTICE: $100,000 · EnvironmentEARTHJUSTICEENVIRONMENT CALIFORNIA RESEARCH AND POLICY CENTER: $95,000 · EnvironmentENVIRONMENT CALIFORNIA RESEARCH AND POLICY CENTERSIERRA NEVADA ALLIANCE: $65,000 · EnvironmentSIERRA NEVADA ALLIANCEGREENBELT ALLIANCEPEOPLE FOR OPEN SPACE: $40,000 · EnvironmentGREENBELT ALLIANCEPEOPLE FOR OPEN SPACESonoma Ecology Center: $21,500 · Environment+2 more: $1,000 · EnvironmentSEACOLOGY: $75,000 · OtherSEACOLOGYMarine Conservation Institute: $66,000 · OtherMarine Conservation InstitutePoint Blue Conservation Science Conservation Service: $50,000 · OtherPoint Blue Conservation Science Conse…Point Reyes Bird Observatory Conservation Service: $40,000 · OtherPoint Reyes Bird Observatory Conserva…LIFEHOUSE INC: $10,088 · OtherBoys & Girls Club: $9,250 · Other+13 more: $21,039 · Other+13 moreThe Climate Center: $100,000 · EducationThe Climate C…+1 more: $500 · EducationKQED INC: $7,500 · Arts & CultureSONOMA EARTH SCHOOL: $1,000 · Arts & CultureMAUI FOOD BANK INC: $5,181 · Food & NutritionCENTER FOR AGRICULTURAL RESILIENCE: $1,000 · Food & NutritionMARIN AGRICULTURAL LAND TRUST: $500 · Food & NutritionHomeless Action Sonoma Inc: $2,000 · Human ServicesNORTH BAY CHILDRENS CENTER INC: $1,500 · Human ServicesSOCIETY OF ST VINCENT DE PAUL ARCHDIOCESAN COUNCIL OF INDIANAPOLIS INC: $2,500 · Religion
Environment$427,500Other$271,377Education$100,500Arts & Culture$8,500Food & Nutrition$6,681Human Services$3,500Religion$2,500

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

25%50%75%100%$1.0M$10M$100Mgrantee revenue →↑ funder's share of their budgetGOODPOWER EDUCATION FUND INC: $105,000 over 2y, 0.7% of budgetThe Climate Center: $100,000 over 2y, 2.1% of budgetEARTHJUSTICE: $100,000 over 2y, 0.0% of budgetENVIRONMENT CALIFORNIA RESEARCH AND POLICY CENTER: $95,000 over 2y, 7.3% of budgetSEACOLOGY: $75,000 over 2y, 1.2% of budgetSIERRA NEVADA ALLIANCE: $65,000 over 2y, 2.6% of budgetGREENBELT ALLIANCEPEOPLE FOR OPEN SPACE: $40,000 over 1y, 2.0% of budgetSonoma Ecology Center: $21,500 over 2y, 0.6% of budgetLIFEHOUSE INC: $10,088 over 2y, 0.0% of budgetKQED INC: $7,500 over 1y, 0.0% of budgetMAUI FOOD BANK INC: $5,181 over 1y, 0.1% of budgetSOCIETY OF ST VINCENT DE PAUL ARCHDIOCESAN COUNCIL OF INDIANAPOLIS INC: $2,500 over 1y, 0.0% of budgetSOROPTIMIST INTERNATIONAL OF NOVATO INC: $2,000 over 2y, 1.0% of budgetHomeless Action Sonoma Inc: $2,000 over 2y, 0.2% of budgetNORTH BAY CHILDRENS CENTER INC: $1,500 over 1y, 0.0% of budgetSIERRA INSTITUTE FOR COMMUNITY & ENVIRONMENT: $1,000 over 1y, 0.0% of budgetGRAND CIRCLE FOUNDATION INC: $1,000 over 1y, 0.0% of budgetRESONATE WORKSHOPS: $1,000 over 1y, 0.2% of budgetSONOMA EARTH SCHOOL: $1,000 over 1y, 0.4% of budgetCENTER FOR AGRICULTURAL RESILIENCE: $1,000 over 1y, 0.7% of budgetMARIN AGRICULTURAL LAND TRUST: $500 over 1y, 0.0% of budgetSonoma Valley Mentoring Alliance: $500 over 1y, 0.1% of budgetNATIONAL TROPICAL BOTANICAL GARDEN: $500 over 1y, 0.0% of budgetCALIFORNIA WATERFOWL ASSOCIATION: $500 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.

Marin Community Found…Sonoma County Communi…The San Francisco Fou…McNabb FoundationResources Legacy FundImpactassetsincPatagoniaorgWomen Giving as One I…Leonard & Beryl Buck …The Joseph and Vera L…Bothin FoundationMorgan Stanley Global…
Marin Community FoundationCA23.9× affinity10 shared granteesties to 11 of 11Hover any node to trace its alignments.Compare side by side →

Open a dossier: Marin Community Foundation · Sonoma County Community Foundation · The San Francisco Foundation · McNabb Foundation · Resources Legacy Fund · Impactassetsinc · Patagoniaorg · Women Giving as One Inc · Leonard & Beryl Buck Foundation · The Joseph and Vera Long Foundation · Bothin Foundation · Morgan Stanley Global Impact Funding Trust Inc

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.
04Through Plinth

Warm introductions · Powered by PlinthPlus

How do I get to Arntz Family Foundation?

Find your warmest path to Arntz Family Foundation 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 37 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 2023, released 2023. Filings run roughly 12 to 24 months behind; figures are dated accordingly.

Possibly out of date. A more recent filing (FY2025) is on record and reports $843k of grant expense with no grantee named in the published copy. A private foundation itemizes every grant it makes, so a return carrying none has filed its list as an attachment that the public copy does not include. The figures above are therefore from FY2023, the most recent year this funder’s grantee list reached the public record.

Source object · view filing

Play a game based on Arntz Family’s filings →

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