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Horizon Advisors
Horizon Advisors was established in 1999 by Larry Maddox and Joe Thomson. Their prior CPA and tax advisory work supplied the initial client relationships that...
Horizon Advisors
Horizon Advisors was established in 1999 by Larry Maddox and Joe Thomson. Their prior CPA and tax advisory work supplied the initial client relationships that evolved into the current multi-family office platform. The firm allocates across private equity, real estate, hedge funds, private credit, infrastructure, and secondaries. It also executes direct co-investments and SPVs. Confirmed investment stages include buyout, growth equity, and venture capital. Geographic reach covers North America, Europe, Asia, and the Middle East & Central Asia. Technology emphases include AI/ML, biotech, and cybersecurity. No AUM figure or professional headcount appears in public materials. The firm lists an office in Westlake Village, California in addition to its Houston headquarters. No dated operational events from the past 24 months are recorded. Wealth origin traces directly to the founders' tax and accounting practice rather than a single operating company or industrial fortune.
General information
Firm type
Multi Family Office
Year founded
1999
AUM
Undisclosed
Location
Region
North America
Country
United States
City
Mesa
Corporate office
Houston, TX, United States
Additional offices
Westlake Village, CA, United States
Principals
Don Martin
CFP
Altss tracks 2 additional named team members for this firm — including direct investment leads, IR, and operating principals not listed on the public website.
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Frequently asked questions
Who runs investment decisions at Horizon Advisors?
Larry Maddox and Joe Thomson founded the firm. Don Martin is listed as a CFP on the firm's LinkedIn.
How does Horizon Advisors source proprietary deal flow?
The firm draws on relationships developed through the founders' prior CPA and tax advisory practice.
Is Horizon Advisors structured as a single family office or does it operate more like a venture firm?
It is organized as a multi-family office serving multiple high-net-worth households.
Does Horizon Advisors participate in fund commitments or only direct deals?
It uses both fund-of-funds commitments and direct co-investments or SPVs.
What investment stages does Horizon Advisors typically target?
The firm targets buyout, growth, and venture capital stages.
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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