Thomas Siebel

Thomas Siebel is an American businessman in the technology industry, born in 1952, based in California, with an estimated net worth of ~$4.1B. He is associated with C3.ai, Inc. (ticker: AI), a software company, which appears in SEC EDGAR filings tied to his name and related entities. Wikidata SEC EDGAR

Business & SEC Activity

SEC EDGAR shows C3.ai, Inc. (AI) as an operating company in “Services—Prepackaged Software,” with 536 total filings and 412 insider filings. Recent filings include multiple Form 4 reports (insider transaction disclosures) in early 2026 and Form 144 filings (a notice of proposed sale of restricted or control securities) on 2026-02-02 and 2025-12-31. The volume and recency of Form 4 filings indicate frequent reported insider transactions. SEC EDGAR

Philanthropy

ProPublica-reported 2023 Form 990 data lists three California-based foundations: Siebel Scholars Foundation, Siebel Family Charitable Foundation, and Thomas And Stacey Siebel Foundation. Across these foundations, total assets were $117,301,251 in 2023, and total grants paid were reported as $0, including $0 grants paid by the largest foundation with $116,780,977 in assets. ProPublica 990

Political Activity

FEC data shows 100 contributions totaling $1,569,668.38 from 2025-02-28 to 2025-12-31. The party breakdown reported $871,668.38 to Republicans, $5,000 to Democrats, and $693,000 to PAC/Other, with top recipients including Grow the Majority ($547,000), NRCC ($310,099.90), and the Republican National Committee ($253,500). The reported giving in this period was heavily weighted toward Republican recipients and committees. FEC