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· Private foundation

Arntz Family Foundation

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.

$531k
Granted FY2023
27
Grants FY2023
5
States reached
$50k
Largest
01What you fundRead
02Your edgeRead
03Your fieldRead
04Through PlinthRead
01What you fund
0191% classified

What you funded, over time

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

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

Where the money goes

Your grants by size, and where they go.

The 27 grants below total $404,396 — the rows itemised in this filing. The $531,397 headline is the total grant expense reported on the return, so the remaining $127,001 is giving the schedule does not break out: grants under the $5,000 itemisation floor, grants to individuals, and grants reported on other schedules. Every figure below describes the itemised 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
$9.9M
Total assets
Largest grants
RecipientAmount
Action for the Climate Emergency, Inc$50,000
Earthjustice Legal Defense Fund$50,000
Point Blue Conservation Science Conservation Service$50,000
The Climate Center$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
02Your 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.

78%of every dollar goes to organizations you’ve 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

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

  • 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

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

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

03Your 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
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
2
Sonoma Mountain Institute
Environment
3
Sonoma Botanical Garden
—
4
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
5
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.

—
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
Ecology Center

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

Environment
8
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
9
CarbonPlan

Improving the transparency and scientific integrity of climate solutions through open data and tools.

Environment
10
Californians Against Waste Foundation

Research, develop and promote waste reduction policies and programs

Environment
11
San Francisco Bay Bird Observatory

The San Francisco Bay Bird Observatory is dedicated to the conservation of birds and their habitats through science and outreach.

Environment
12
Northcoast Environmental Center

To promote understanding of the relations between people and the biosphere and to conserve, protect, and celebrate terrestrial, aquatic, and marine ecosystems of northern California and southern Oregon.

Environment

For reference, the grantee most central to the portfolio’s shape is Environment California Research and Policy Center and 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.

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 backsteadyGovernment Accountability &…Developmental Disabilities …Food Pantries and AssistanceEarly Childhood Care CentersPrivate Grantmaking Foundat…Christian Outreach Ministri…Environmental Advocacy and …
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 30 years old; the field is 14. You back the established end — and your money leans older still.

THE FIELDby orgYOUR GRANTEESby number24%9%<5yr15%4%5–10yr20%13%10–20yr17%39%20–35yr11%13%35–55yr13%22%55yr+
THE FIELDby orgYOUR MONEYby value24%0%<5yr15%0%5–10yr20%19%10–20yr17%52%20–35yr11%0%35–55yr13%28%55yr+

The field is 24% startups (under 5 years old) — 9% 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 14% of the field you don’t fund.

orgs you fund
0.0%0/26
the rest of the field
14%
26,003/186,952

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.

03the grantee network

24 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. 24 of the 37 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.

0
Load-bearing (≥25% of a budget)
7
Early backer (in before they grew)
24/24
Grantees still filing
20/24
Grew since you first funded

Where your money sits — by cause, 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 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 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 budgetHomeless Action Sonoma Inc — $2,000 over 2y, 0.2% of budgetSOROPTIMIST INTERNATIONAL OF NOVATO INC — $2,000 over 2y, 1.0% of budgetNORTH BAY CHILDRENS CENTER INC — $1,500 over 1y, 0.0% of budgetRESONATE WORKSHOPS — $1,000 over 1y, 0.2% of budgetSIERRA INSTITUTE FOR COMMUNITY & ENVIRONMENT — $1,000 over 1y, 0.0% of budgetGRAND CIRCLE FOUNDATION INC — $1,000 over 1y, 0.0% 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 budgetCALIFORNIA WATERFOWL ASSOCIATION — $500 over 1y, 0.0% of budgetNATIONAL TROPICAL BOTANICAL GARDEN — $500 over 1y, 0.0% 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.

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

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.

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 directly from IRS e-file XML — your own 990/990-PF and the multi-year returns of the 37 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 2023, released 2023. Filings run roughly 12–24 months behind; figures are dated accordingly.

Possibly out of date. A more recent filing (FY2024) is on record and reports $595k 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

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