Thomas Siebel
American businessman
Source: Wikidata — retrieved 10/11/2026 (wikidata)Dispute
Profile Summary
A net worth stated in this summary may be out of date.
Thomas Siebel is an American businessman in California's technology industry, born in 1952. He has an estimated net worth of ~$4.1B and is associated in SEC records with C3.ai, a prepackaged-software company trading under ticker AI. Wikidata SEC EDGAR
Business & SEC Activity
SEC records identify C3.ai as an operating company in the prepackaged-software industry and list 435 insider filings. Recent filings include multiple Form 4 reports in May and June 2026; Form 4 reports disclose changes in an insider's ownership of company securities, while Form 144 notices a proposed sale of restricted or control securities. SEC EDGAR A reported August 2026 article said Siebel sold 453,000 C3.ai shares for $4.8 million. NewsAPI
Philanthropy
The Thomas and Stacey Siebel Foundation reported $116.8 million in assets and $6.5 million in grants paid in tax year 2023. The Siebel Family Charitable Foundation reported about $498,626 in assets and $44,800 in grants paid that year; together, the two foundations reported $117.3 million in assets and $6.5 million in grants paid. ProPublica 990
Political Activity
FEC records show at least 100 federal contributions in the most recent 100 contributions on file, covering a sampled period from August 7, 2025, to May 7, 2026. These sampled records total $2,358,714.11: $1,225,230.76 was classified as unknown party, $1,128,483.35 as Republican, and $5,000 as Democratic. The largest listed recipients in the sample were Grow the Majority ($1,047,000), NRCC ($595,099.90), Put Alaska First ($100,000), NRSC ($100,000), and McCormick Victory Fund ($30,000). FEC
These donations are matched to this person by name only, so some may belong to a different person with the same name: FEC filings can include a donor's employer and city, but our matching does not check them against what we know about this person.
In the News
An August 14, 2026 article reported that C3.ai CEO Thomas Siebel sold 453,000 shares for $4.8 million. NewsAPI
U.S. Presence
Philanthropy
Foundations are matched to a person by name, not by trustee records — so a same-surname family foundation can land here in error. Every entity below links to its full IRS filing; if one doesn’t belong, tell us at hello@skylarkcreations.com and we’ll pull it.
Political Contributions
These figures cover the 100 most recent of 692 federal contributions on file, not the full record. The total, party split, top recipients and dates below are all computed over that sample, so each is a floor rather than a complete figure.
By Party (in the sample)
Every party in this sample is listed here. The bars are rounded for display; unrounded they total exactly $2,358,714.11.
Top Recipients (in the sample)
Matched by name only. These donations are matched to this person by name only, so some may belong to a different person with the same name: FEC filings can include a donor's employer and city, but our matching does not check them against what we know about this person.
SEC Filings
Associated Companies
Entities appearing alongside this person in SEC full-text search — an association, not necessarily ownership or control. Follow each link to the primary SEC record to judge for yourself.
Recent Insider Filings
Score Breakdown
The giving score is a weighted average of 2 components. The formula is open and versioned — the weight percentages below show how much each component contributes to the final score.
Evidenced charitable giving — built on what they actually give each year, not parked assets. Dominated by generosity (annual giving relative to net worth — the share of your fortune you give), plus the absolute scale of that giving, plus a small nudge for signing the Giving Pledge (a commitment, not a realized action).
Data: ProPublica 990 charitable disbursements, net worth, The Giving Pledge registry
How much sourced public record we hold about this person — net worth, SEC filings, foundation 990s, news coverage, Wikidata. It measures our coverage, not how open the person is. Each further kind of record scores higher, up to eight. Political donation records matched to a person by name alone are not counted: they may belong to someone else with the same name. From October 7, 2026, our own AI-written summary and the profile photo are not counted either — neither is a public record — so grades that leaned on them moved down that day.
Data: SEC EDGAR, ProPublica 990s, GDELT / NewsAPI, Wikidata
Formula (v2): Giving score = 65% x Philanthropy + 35% x Data coverage
Scored on 10/16/2026 on a 0–100 scale. The score uses only the signals we have populated data for. Goal Impact, Controversy, and Community Approval are deferred until that data exists — Phase 1 goal adoption, controversy detection, and community votes respectively.
All data is sourced from public records. Each section links to its original source. View on Wikidata