· Private foundation
Harold Kl Castle Foundation
Its FY2024 filing reports that it accepted unsolicited grant applications.
What you funded, over time
Every grant placed by its stated purpose and the recipient’s mission, by year — across FY2020–2024.
Where the money goes
Your grants by size, and where they go.
By grant size · FY2024
- Under $10k20 grants · $102k
- $10k–50k45 grants · $1.1M
- $50k–250k35 grants · $2.9M
- $250k+6 grants · $2.8M
| Recipient | Amount |
|---|---|
| SOCIAL FINANCE INC | $550,000 |
| UNIVERSITY OF HAWAII FOUNDATION | $529,240 |
| HAWAII COMMUNITY FOUNDATION (HCF) | $500,000 |
| KUAAINA ULU AUAMO (KUA) | $500,000 |
| HAWAII COMMUNITY FOUNDATION (HCF) | $400,000 |
| THE NATURE CONSERVANCY OF HAWAII | $280,000 |
| UNIVERSITY OF HAWAII FOUNDATION | $214,286 |
| HAWAII HOSPITAL EDUCATION AND RESEARCH FOUNDATION (HHERF) | $150,000 |
| WINDWARD SCHOOL DISTRICT | $150,000 |
| UNIVERSITY OF HAWAII FOUNDATION | $150,000 |
| PURPLE MAIA | $145,000 |
| HAWAII CONSERVATION ALLIANCE FOUNDATION | $132,715 |
| RESOURCES LEGACY FUND | $120,000 |
| THE AMERICAN AI FORUM AKA AI EDUCATION PROJECT | $115,000 |
| COLLEGE SUMMIT INC DBA PEERFORWARD | $103,163 |
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.
Your human-services grants (FY20–24, $1.3M) land where the poverty rate runs at 10%, against an area that typically sits at 10%. 11% of those dollars go to grantees based in above-average-need neighborhoods. Your grants skew toward lower-need ZIPs.
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
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.
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.
And the relationships you keep tend to grow: grantees you re-up on have seen median revenue of +58% since the first grant, against +26% for the ones you funded once.
98 repeat relationships — 51 still active in FY2024, 47 since wound down; 30 grantees were first funded in FY2024 (too recent to call).
How the two cohorts compare
Organizations
Total granted
Median revenue growth · since first grant
Still filing today
New vs renewed · share of each year
In FY2024, 70% of grant dollars renewed an existing relationship; $1.7M went to new ones.
Where new relationships form · theme of each grantee’s first grant
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
- UOUNIVERSITY OF HAWAII FOUNDATION5× · 2020–2024 · $7.7M · revenue +132%
- 5I50CAN INC5× · 2020–2024 · $718k · revenue +841%
- RLRESOURCES LEGACY FUND5× · 2020–2024 · $567k · revenue +114%
Funded once
- HHHISTORIC HAWAI'I FOUNDATIONone grant, 2023 · $175k · revenue +8%
- KVKANEHUNAMOKU VOYAGING ACADEMYgraduatedone grant, 2021 · $173k · revenue +172%
- HCHAWAIIAN COMMUNITY ASSETS INCgraduatedone grant, 2021 · $172k · revenue +98%
Repeat = funded in two or more distinct years; growth and survival are read from each grantee’s own subsequent IRS filings.
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.
Papahana kuaola's mission is to create quality educational programs focused on environmental restoration and economic sustainability fully integrated with hawaiian knowledge in order to exemplify a lifestyle respectful of kanaka, `aina,…
Our mission is to protect, perpetuate, and enhance the cultural and natural landscape of the kiholo bay area through collaborative management and active community stewardship.
Growing hawaii's communities through culturally based forms of innovative learning, leadership development, and collaborative networking in wahi kupuna stewardship.
To re-establish the systems that sustain our community through educational initiatives and land-based practices that cultivate abundance, regenerate responsibilities, and promote collective health and well being.
To support education primarily in the Waianae community on the island of Oahu. Support may included, but not be limited to, professional development, student support services, and community engagement. As educators on the Waianae coast,…
The kohala center is an independent community-based center for research, conservation, and education.
Protecting and promoting the marine biodiversity of Hawai'i through coral restoration, ecological monitoring, regenerative tourism, and cultural integration
For reference, the grantee most central to the portfolio’s shape is Kipahulu Ohana Inc and the most unlike its peers is Marine Applied Research and Exploration. Resemblance is measured on each organization’s own IRS 990 mission text; it reflects how work is described, not its quality or impact.
Your grantees are a median of 21 years old; the field is 15. You back the established end — and your money leans older still.
The field is 24% startups (under 5 years old) — 2% of your grantees by number, and just 0% of your money.
The orgs you fund almost never close — 1% lost their exemption, against 13% of the field you don’t fund.
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.
131 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. 131 of the 208 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.
Where your money sits — by cause, then by grantee
Showing your 200 largest grantees by grant value.
Each org by its size and your share of it — top-left is where you’re load-bearing
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.
- Who funds UNIVERSITY OF HAWAII FOUNDATION ↗
- Who funds HAWAII COMMUNITY FOUNDATION ↗
- Who funds THE NATURE CONSERVANCY ↗
- Who funds 50CAN INC ↗
- Who funds RESOURCES LEGACY FUND ↗
- Who funds HAWAII CONSERVATION ALLIANCE FOUNDATION ↗
- Who funds KUALOA-HEEIA ECUMENICAL YOUTH PROJECT ↗
- Who funds BOBBY BENSON CENTER ↗
- Who funds PURPLE MAIA FOUNDATION ↗
- Who funds HOOKUAAINA ↗
- Who funds CHAMBER OF COMMERCE OF HAWAII ↗
- Who funds CENTER FOR TOMORROW'S LEADERS ↗
- Who funds HUI O HAUULA ↗
- Who funds COLLEGE SUMMIT INC ↗
- Who funds POLYNESIAN VOYAGING SOCIETY ↗
- Who funds WAIMANALO HEALTH CENTER ↗
- Who funds HAWAII WORKFORCE PIPELINE INC ↗
- Who funds CONSERVATION INTERNATIONAL FOUNDATION ↗
- Who funds KAI LOA INC ↗
- Who funds Castle Medical Center dba Adventist Health Castle ↗
- Who funds HAWAII ALLIANCE OF NONPROFIT ORGANIZATIONS ↗
- Who funds MALAMA HONUA PUBLIC CHARTER SCHOOL FOUNDATION ↗
- Who funds PAEPAE O HE'EIA ↗
- Who funds KAULUAKALANA ↗
- Who funds HUI MALAMA O KE KAI FOUNDATION ↗
- Who funds MANOA HERITAGE CENTER FKA MANOA VALLEY CULTURAL HERITAGE FOUND ↗
- Who funds HISTORIC HAWAI'I FOUNDATION ↗
- Who funds KANEHUNAMOKU VOYAGING ACADEMY ↗
- Who funds HAWAIIAN COMMUNITY ASSETS INC ↗
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.
Open a dossier: Atherton Family Foundation · Aloha United Way Inc · Trustees of the Estate of Bernice Pauahi Bishop Dba Kamehameha Schools · The Harry and Jeanette Weinberg Foundation Inc · Bank of Hawaii Charitable Fdn · J Watumull Fund · First Insurance Company of Hawaii Charitable Foundation · Tradewind Group Foundation · Kosasa Foundation · Central Pacific Bank Foundation · Kaiser Foundation Health Plan Inc · Stupski Foundation
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 Harold Kl Castle 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 or a single department — and drag the year to watch it move.
- Social Finance Inc — 12% of income from government
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.
Warm introductions · Powered by PlinthPlus
How do I get to Harold Kl Castle Foundation?
Find your warmest path to Harold Kl Castle 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.