Single Family Office

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OnDean

OnDean is a family investment office led by Andrew Sieja, based in Delaware. OnDean has made five investments to date. Their most recent investment was in...

OnDean

OnDean is a family investment office led by Andrew Sieja, based in Delaware. OnDean has made five investments to date. Their most recent investment was in Justice Bid, a private equity deal made on April 14, 2025.

General information

Firm type

Single Family Office

Location

Region

North America

Country

United States

City

Chicago

Corporate office

Chicago, IL, United States

Principals

Ronald J. Gidwitz

Principal

Sector focus

Real EstateHealthcare ServicesConsumer GoodsEducation

Frequently asked questions

What is OnDean?

OnDean is a single family office headquartered in Chicago, United States.

Where is OnDean headquartered?

OnDean is headquartered in Chicago, United States, in the North America region.

What does Altss track for OnDean?

Altss maintains an OSINT-verified profile of OnDean 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), assets (real estate, public market positions, private companies, art and cultural holdings, philanthropy and foundations), and network (club memberships, associations, and event participation). Detailed values are available to Altss subscribers.

What is OnDean's website?

OnDean's public website is www.ondean.com. Verified contact details for principals and decision-makers are available to Altss subscribers.

What type of firm is OnDean?

OnDean is classified by Altss as a Single Family Office, operating from United States within the North America region.

How does Altss source intelligence on OnDean?

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 OnDean's Altss profile last updated?

OnDean's profile on Altss was last refreshed on June 3, 2026. Continuous updates are applied as new public information is verified.

Profile maintained by 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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