# Source: https://businessownerindex.com/founder-reference/people/john-k-castle-q16727878/

U.S. founder reference library

# John K. Castle

Recorded founding associations · Castle Harlan

## Founding associations

John K. Castle is recorded as a founder of [Castle Harlan](https://businessownerindex.com/company-reference/castle-harlan-q5050106/) in the cited public company records. The person record describes John K. Castle as American businessman.

## [Castle Harlan](https://businessownerindex.com/company-reference/castle-harlan-q5050106/)

private equity firm. Recorded founding year: 1987.

Explore the [Castle Harlan company reference](https://businessownerindex.com/company-reference/castle-harlan-q5050106/) for the recorded cofounders, business context, and company-specific source trail.

## More from the public record

These details describe the cited record as reviewed on October 9, 2026. They may describe an earlier period; they are not a current employment or operating-status check.

Education in public record

Massachusetts Institute of Technology · [View source field](https://www.wikidata.org/wiki/Q16727878#P69)

## Follow the founding team

John K. Castle’s association with [Castle Harlan](https://businessownerindex.com/company-reference/castle-harlan-q5050106/) can be researched alongside the company source record. The company’s recorded founding year is 1987. The shared company record is the evidence for this connection; it does not establish that these people currently work together.

This reference library documents public founding associations. It is separate from our revenue-qualified growth profiles. Founding does not establish current ownership, employment, company revenue, or an AE client relationship.

## Public sources

- [Wikidata public record Q16727878](https://www.wikidata.org/wiki/Q16727878): person identity and public description.
- [Wikidata public record Q5050106](https://www.wikidata.org/wiki/Q5050106): founder association with Castle Harlan.

## Using this founder record

A founding association can remain historically meaningful after someone's role changes. This profile does not label John K. Castle as a current owner or executive, estimate personal income, or claim the person uses AE Tax Advisors. Confirm present responsibilities through current company information.

For the separate collection with published historical growth evidence, explore our [growth-profile directory](https://businessownerindex.com/directory/). To add a company biography or correct an association, submit public evidence through the profile update form.[Browse founder reference ↗](https://businessownerindex.com/founder-reference/)[Submit a sourced correction ↗](https://businessownerindex.com/get-featured/?request=update)

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