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TomEnterprise
Thomas Siebel's single-family office, TomEnterprise, manages wealth from the Siebel Systems sale alongside a concentrated stake in C3 AI.
TomEnterprise
Family office, private investor, and active owner | As a family office, a private investor, and an active owner, TomEnterprise AB engages in minority and majority investments in both public and private businesses. Our investments primarily target companies operating in the energy and health sectors, with a specific emphasis on innovative solutions addressing future challenges. TomEnterprise AB supports businesses in various stages of development by providing a combination of capital and expertise.
General information
Firm type
Single Family Office
Year founded
—
AUM
Undisclosed
Location
Region
North America
Country
United States
City
Seattle
Corporate office
Seattle, WA, United States
Additional offices
Palo Alto, CA · San Francisco, CA · Bethesda, MD
Principals
Thomas Siebel
Principal
Sector focus
Frequently asked questions
Who runs investment decisions at TomEnterprise?
Investment decisions at TomEnterprise are driven by Thomas Siebel, who founded and serves as principal. The office does not publicly list a separate CIO or investment committee, and no external investment staff are named in public records. Operational decisions related to its portfolio holdings appear to flow through Siebel directly, consistent with a tightly held single-family office structure.
How does TomEnterprise source proprietary deal flow?
TomEnterprise sources deals primarily through Thomas Siebel's professional network built over three decades spanning enterprise software, energy, and government technology advisory roles. The office's direct investment in ventures like C3 AI — where Siebel serves as chairman and CEO — suggests deal flow originates from Siebel's own entrepreneurial pipeline rather than through fund-manager relationships or broker-intermediated channels. No fund-commitment data is publicly available to indicate co-investment sourcing patterns.
Is TomEnterprise structured as a single family office or does it operate more like a venture firm?
TomEnterprise operates as a single family office managing Siebel family capital. Unlike a venture firm, it does not raise external limited-partner funds, charge management fees, or publicly market investment vehicles. The office's overlap with C3 AI — a publicly traded company where Siebel is chairman and CEO — means part of the portfolio has institutional co-owners via the public markets, but TomEnterprise itself remains a private wealth-management entity.
What investment stages does TomEnterprise typically target?
TomEnterprise's known investments suggest a preference for ventures where Thomas Siebel can exert founder-level control or operational influence, as seen with C3 AI, which he incubated from inception through IPO. The office also makes direct asset purchases in real estate and farmland, bypassing structured-fund stages entirely. Evidence of early-stage venture participation outside Siebel-founded enterprises is not documented in public records.
Where does the underlying wealth come from?
The wealth managed by TomEnterprise originates predominantly from the sale of Siebel Systems to Oracle for approximately $5.85 billion in 2006. Thomas Siebel, as founder and majority shareholder, received an estimated $2.5 billion from the transaction. Subsequent appreciation has been driven by Siebel's post-2006 ventures, most notably the founding and public listing of C3 AI in 2020.
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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