Userfox
DefunctYC W11San Francisco, US · Founded 2011 · 2 employees · 3 known investors
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Userfox provides email automation software that helps companies reduce user churn by sending targeted messages triggered by user behavior, including welcome sequences, inactivity alerts, and custom-defined events.
Also known as Serious Fox Corp
Founders & leadership· Y Combinator alumni (W11)
Userfox was founded in 2011 by Cesar Alaniz and Peter Clark.


Investors · 3
How we know: funding news · open dataset · 500 Global portfolio 2026-08 · Y Combinator's founder network · Not right? Tell us
How we know: the Y Combinator directory · funding news · open dataset · 5k.vc investor directory · Not right? Tell us
How we know: funding news · Y Combinator's founder network · Not right? Tell us
Related companies · 5
Companies working in the same space as Userfox.
Legal entities · 1
corporate structureIn the news
Frequently asked questions
- What does Userfox do?
- Userfox provides email automation software that helps companies reduce user churn by sending targeted messages triggered by user behavior, including welcome sequences, inactivity alerts, and custom-defined events.
- Who founded Userfox?
- Userfox was founded by Cesar Alaniz, Peter Clark in 2011.
- Who are Userfox's investors?
- Userfox's investors include 500 Global, Y Combinator, Point Nine.
- Where is Userfox headquartered?
- Userfox is headquartered in San Francisco, US.









