# C3 AI vs StackAI: who uses which

On usedby, 44 companies use C3 AI and 21 use StackAI. 1 company uses both, including BAE Systems. Counts include every proof level, job-post signals included; each company keeps its proof level on each side. Latest check 2026-10-11: 65 of 65 public lines checked.

## Side by side

|  | [C3 AI](https://www.usedby.ai/tools/c3-ai.md) | [StackAI](https://www.usedby.ai/tools/stackai.md) |
|---|---|---|
| Public customers | 44 | 21 |
| Confirmed | 7 | 8 |
| Observed | 37 | 13 |
| Signals (job posts) | 0 | 0 |
| Top industries of customers (every proof level) | Aerospace & Defense (8), Energy, Utilities & Cleantech (8), Government & GovTech (5) | Investment & VC (4), Banking & Mortgages (3), Fintech & Payments (2) |
| Category | Enterprise AI platforms | Enterprise AI platforms |
| Your data | — | Not used to train models by default. ([stackai.com](https://www.stackai.com/privacy), checked 2026-10-08) |
| Data processing terms | — | A data processing agreement is available. ([stackai.com](https://www.stackai.com/privacy), checked 2026-10-08) |
| Free trial | — | Free trial or free plan available. ([stackai.com](https://www.stackai.com/pricing), checked 2026-10-08) |
| Integrations | — | 15Five, Abstract API, Ahrefs, Airops, Airtable, Algolia, Apollo, Appfolio, Asana, Ashby, Atlassian, AWS Athena ([stackai.com](https://www.stackai.com/integrations), checked 2026-10-08) |
| Vendor status | — | Acquired by Asana, according to the vendor's homepage. ([stackai.com](https://www.stackai.com/), checked 2026-10-08) |

## Companies that use both

Every proof level counts; the proof level of each side is shown, strongest proofs first. The first public proof is not an adoption date.

| Company | Proof, C3 AI | Proof, StackAI | First public proof, C3 AI | First public proof, StackAI |
|---|---|---|---|---|
| [BAE Systems](https://www.usedby.ai/companies/bae-systems.md) | Observed | Observed | On or before October 2026 | On or before October 2026 |

## Published results

Reviewed stories only; usedby did not measure the figures.

- C3 AI: [Global HealthTech Company](https://www.usedby.ai/case-studies/global-healthtech-company-c3-ai.md): **4 weeks**: “In just 4 weeks, C3 AI configured the C3 AI Supply Network Risk application for 42 critical ventilator SKUs (stock keeping units)” (captured by usedby 2026-10-09)
- C3 AI: [Missile Defense Agency](https://www.usedby.ai/case-studies/missile-defense-agency-c3-ai.md): **99%**: “99% reduction in the time to generate threat data, from weeks to minutes” (captured by usedby 2026-10-08)
- StackAI: [Nova Talent](https://www.usedby.ai/case-studies/nova-talent-stackai.md): **60%**: “60% cost reduction in applicant evaluation” (captured by usedby 2026-10-08)
- StackAI: [Varos](https://www.usedby.ai/case-studies/varos-stackai.md): **800+ hours**: “800+ hours saved by eliminating repetitive manual research” (captured by usedby 2026-10-08)

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Source: https://www.usedby.ai/compare/c3-ai-vs-stackai · How we check: https://www.usedby.ai/methodology