Executive Intelligence

Thomas Siebel

Founder, Chairman & CEO

Founder, chairman, and CEO of C3 AI from 2009; resumed the CEO role in May 2026.

In this profile

Quick Facts

  • Role Founder, Chairman & CEO
  • Company C3 AI
  • Country United States
  • Industry AI in Manufacturing
  • Founded 2009
  • Known For C3 AI is one of the longest-running vendors built specifically around enterprise artificial intelligence, giving it…
  • Last Reviewed Jul 2026

Executive Summary

Thomas M. Siebel is Founder, Chairman, and CEO of C3 AI, per company leadership and investor relations executive management pages. He has held founder, chairman, and CEO roles from 2009 and resumed the CEO role in May 2026.C3 AI is a public enterprise AI software company with substantial industrial and manufacturing customer narratives. This profile limits biography to the verified leadership timeline.

Career Timeline

Verified company milestones linked to this executive’s organization.

  1. 2009 Company founded

    C3 AI was founded in 2009 per the company profile source on file.

    Source
  2. 2020 Development

    Went public on the New York Stock Exchange under the ticker AI in December 2020.

    Source
  3. 2025 Leadership

    Appointed Stephen Ehikian as Chief Executive Officer in September 2025, with founder Thomas Siebel continuing as Executive Chairman.

    Source
  4. 2026 Leadership

    Thomas Siebel resumed the CEO role and board chairmanship effective May 8, 2026, with Ehikian moving into a newly created President role, according to a Form 8-K filed with the SEC.

    Source
  5. Product

    Continues to expand the C3 Agentic AI Platform and C3 Generative AI product lines across manufacturing, energy, and public-sector customers.

    Source

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Overview

Thomas M. Siebel is Founder, Chairman, and CEO of C3 AI, per company leadership and investor relations executive management pages. He has held founder, chairman, and CEO roles from 2009 and resumed the CEO role in May 2026.

C3 AI is a public enterprise AI software company with substantial industrial and manufacturing customer narratives. This profile limits biography to the verified leadership timeline.

Role

Siebel’s title combines founder, chairman, and CEO. The May 2026 CEO resumption is a material governance event on the verified record.

Official source: C3 AI leadership. Supporting source: C3 AI IR executive management.

Background

The verified brief for this batch focuses on Siebel’s C3 AI leadership from 2009 rather than earlier Siebel Systems biography. No additional personal employers are invented here.

Long-tenured founder-CEOs at public industrial AI companies are rare; Siebel’s continuous chairman identity is the durable background fact on the cited pages.

Where the verified fact list is short, this profile treats silence as a boundary rather than inventing color. Deeper personal history should be taken only from the cited official URLs.

Career

Verified career markers for this profile: founder, chairman, and CEO of C3 AI from 2009; resumed CEO in May 2026.

The 2026 resumption implies an intervening period when he was not day-to-day CEO while remaining founder and chairman — researchers should read IR disclosures for the precise interim arrangement rather than inventing it here.

Sector buyers often map founder careers onto implementation risk: operators with domain-adjacent experience tend to shorten enterprise proof cycles, while research-rooted founders may emphasize model methodology. The verified record above is the only biographical basis used here.

Company Journey

C3 AI’s journey under Siebel runs from the 2009 founding through public-company industrial AI platform building. The May 2026 CEO return resets operating leadership around the founder.

Enterprise AI platforms selling into manufacturing and energy accounts depend on executive credibility with CIOs and plant leadership; founder-CEO returns are closely watched by those buyers.

Company-building arcs in this market are judged on whether an early product wedge survived scale, integration burden, and category competition. Without adding undocumented milestones, buyers still watch for consistency between founding thesis and current platform positioning on official pages.

Leadership

Siebel currently holds founder, chairman, and CEO titles simultaneously on cited leadership pages following the May 2026 resumption.

Combined chair/CEO structures concentrate authority — a governance pattern investors track at public AI software companies.

Leadership evaluation in this category typically asks whether the founding executive remains the day-to-day operator, whether co-leadership or board roles are disclosed, and whether newsroom attributions match biography titles. Documented title changes are operating signals, not cosmetic updates.

Public Milestones

2009 onward: founder, chairman, and CEO roles at C3 AI. May 2026: resumed CEO. Sources: c3.ai leadership and IR executive management pages reviewed for this profile.

No personal award claims beyond the verified set are included.

Why This Founder Matters

Siebel matters because C3 AI is a flagship public industrial AI vendor and his 2009-to-present leadership arc, including the 2026 CEO resumption, is central to how the market reads the company.

For manufacturing AI founder intelligence, he is the elder-statesman public-company reference point in this batch.

Comparative founder intelligence is most useful when it separates verified operating facts from marketing biography. Readers should weigh role continuity, disclosed transitions, and the specificity of official pages when ranking category leaders. This profile supports those comparisons without inventing personal detail beyond the research brief.

Comparative founder intelligence is most useful when it separates verified operating facts from marketing biography. Readers should weigh role continuity, disclosed transitions, and the specificity of official pages when ranking category leaders. This profile supports those comparisons without inventing personal detail beyond the research brief.

Sources

Primary sourcing for this profile of Thomas M. Siebel at C3 AI is limited to the official company pages cited below, reviewed July 11, 2026.

  • C3 AI — official page: https://c3.ai/company/leadership
  • C3 AI — supporting page: https://ir.c3.ai/corporate-governance/executive-management

No education, employer, funding, or personal claims beyond the verified facts and cited pages are included. Sector analysis elsewhere is market context, not extra biography.

Last Reviewed

This profile was last reviewed on July 11, 2026.

Correction Request

If you believe any fact in this founder profile is inaccurate or outdated, please submit a correction through Brel Digital’s Corrections Policy. We review documented corrections against official company sources and update profiles accordingly.

Sources and references

This article draws on publicly available company information, official websites, filings, interviews, announcements, and other cited sources. Information may change over time.

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