What else does Lightfern use?

Cloudflare, Fireworks AI, Stripe, Amazon Web Services and Canny, among 16 vendors we hold evidence for.

Which other companies use OpenAI?

10Web, 12ui, 15Five, 1K4.AI and 1mind AI, among 3,285 companies with public evidence.

Companies / Lightfern / OpenAI

Does Lightfern use OpenAI?

Q: Does Lightfern use OpenAI?

Yes. We hold strong evidence for this. Evidence: Subprocessor list.

Yes

We hold strong evidence for this.

The company names it in its own subprocessor list, a statement that this vendor handles its customers' data.

How we know

Subprocessor listNamed as OpenAI, L.L.C.Processes data for the company12 Nov 2026Source

About Lightfern

Lightfern provides an AI email assistant that drafts replies, suggests completions, and answers questions inline within Gmail, Outlook Web, and Superhuman Web. It serves founders, GTM leaders, account executives, product managers, and investors.

Summarized from its homepage on 12 Nov 2026.

Communications Productivity and collaboration

What else Lightfern uses

Lightfern has evidence for 16 vendors. The strongest:

Cloudflare Fireworks AI Stripe Amazon Web Services Canny Datadog Gmail Microsoft 365 Nebius

See the full Lightfern tech stack

Other companies using OpenAI

10Web10web.io

12ui12ui.com

15Five15five.com

1K4.AI

1mind AI1mind.com

24/7 Software247software.com

360REV360rev.com

365agents365agents.com

All 3,285 companies using OpenAI

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