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Harold K.L. Castle Foundation
The Harold K.L. Castle Foundation is a non-profit organization and one of the largest private foundations in Hawaii. Established in 1962 by Harold K.L.
Harold K.L. Castle Foundation
The Harold K.L. Castle Foundation is a non-profit organization and one of the largest private foundations in Hawaii. Established in 1962 by Harold K.L. Castle, it focuses on public education, restoring Hawaii's nearshore ocean areas, building Koolau Oahu communities, and strengthening climate change adaptation. It grants approximately $7 million annually.
General information
Firm type
Endowment / Foundation
Year founded
1962
AUM
—
Location
Region
North America
Country
United States
City
Kailua
Corporate office
1197 Auloa Rd
Frequently asked questions
What is Harold K.L. Castle Foundation?
Harold K.L. Castle Foundation is a endowment / foundation headquartered in Kailua, United States.
When was Harold K.L. Castle Foundation founded?
Harold K.L. Castle Foundation was founded in 1962.
Where is Harold K.L. Castle Foundation headquartered?
Harold K.L. Castle Foundation is headquartered in Kailua, United States, in the North America region.
What does Altss track for Harold K.L. Castle Foundation?
Altss maintains an OSINT-verified profile of Harold K.L. Castle Foundation covering investment focus (ESG policy, ticket size, target IRR, currency preference, regional focuses, industry focuses, technological focuses), team (service providers and advisors), deals (company deals and fund commitments), and network (associations and event participation). Detailed values are available to Altss subscribers.
What is Harold K.L. Castle Foundation's website?
Harold K.L. Castle Foundation's public website is castlefoundation.org. Verified contact details for principals and decision-makers are available to Altss subscribers.
What type of firm is Harold K.L. Castle Foundation?
Harold K.L. Castle Foundation is classified by Altss as a Endowment / Foundation, operating from United States within the North America region.
How does Altss source intelligence on Harold K.L. Castle Foundation?
Altss combines OSINT (open-source intelligence) with regulatory filings, public disclosures, and licensed data partners. Source provenance is tracked to support compliance-ready research workflows.
When was Harold K.L. Castle Foundation's Altss profile last updated?
Harold K.L. Castle Foundation's profile on Altss was last refreshed on June 3, 2026. Continuous updates are applied as new public information is verified.
Profile maintained by Altss using OSINT (open-source intelligence), regulatory filings, licensed data partners, and verified direct submissions. Read the methodology. Last updated: . Continuous refresh with full update cycles at least every 30 days.
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